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superpoop
01-14-2015, 03:13 PM
Hey guys.

I'm now buying a motor for the tbird. Long story.

Anyways the replacement motor has higher mileage on it as it sits but is much too cheap to pass up. What kinda mileage do these motors (especially bearings and piston rings) tend to start wearing out?

Neill

KMT
01-14-2015, 03:19 PM
Lots, but it can depend on if those are hard miles or not? How many miles on the 'new' engine? Can you do an compression test on it or is it already out?

HwyStar
01-14-2015, 05:33 PM
Just get the engine regardless. Then, do what I said in your other post. Newer engines like these have more nickel in them and keep their cross hatch for a long time. Unless the engine has had water sitting in it or oil not changed for LONG time, rings are probably good. When you have the oil pan off, roll the engine over and look for scrapes and polished spots on cylinder walls. If the engines been sitting a while, I would replace the valve springs. They're cheap. Take the oil pump apart. Look for grooves on the housings and pitting in the gears. All that would be easy to do with the engine out, and head off any potential problems. It would be fine.

First car I got with 125k. Changed the oil religiously. Blew hg at 150k. Spun a couple bearings at 215k.

Second car , got with 150k and mud for oil. Changed oil religiously, locked up on way to work 165k. I beat both of these cars hard. I could see a good used engine going to 300k if the bearings and oil pump were fine, or replaced when you looked it over. Oh, and not overheated!

superpoop
01-14-2015, 08:21 PM
Just get the engine regardless. Then, do what I said in your other post. Newer engines like these have more nickel in them and keep their cross hatch for a long time. Unless the engine has had water sitting in it or oil not changed for LONG time, rings are probably good. When you have the oil pan off, roll the engine over and look for scrapes and polished spots on cylinder walls. If the engines been sitting a while, I would replace the valve springs. They're cheap. Take the oil pump apart. Look for grooves on the housings and pitting in the gears. All that would be easy to do with the engine out, and head off any potential problems. It would be fine.

First car I got with 125k. Changed the oil religiously. Blew hg at 150k. Spun a couple bearings at 215k.

Second car , got with 150k and mud for oil. Changed oil religiously, locked up on way to work 165k. I beat both of these cars hard. I could see a good used engine going to 300k if the bearings and oil pump were fine, or replaced when you looked it over. Oh, and not overheated!

this motor is already apart, but was removed just days ago and was a running driving no smoke no knock motor. this will make checking the above a much simpler process. headgaskets (and all other gaskets) will be replaced also.

this is a pretty comprehensive list too, thanks buddy! wasnt sure whether to get a bearing set with it. wouldnt like to break something that isnt broke so i guess ill let it ride out. i doubt i will be doing a huge amount of miles in it anyway so not much of an issue.

if i were to install bearings, this new motor has no knocking or noises of any kind. am i correct in thinking that standard sized bearings are to be used and no crank work needed? or does it all depend on the physical condition rather than going by noise alone?

Neill

1FSTBRD
01-14-2015, 09:28 PM
Ah, the 'ol longevity question! You know, there are times where I'd almost want an odometer on the engine, coupled with some sort of meter for the driver's habits (ie: typically driven hard, or typically driven normally).

bowez
01-14-2015, 09:51 PM
I would suggest rebuilding the heads--new springs and seals at least.

HwyStar
01-15-2015, 05:26 PM
Yeah, that's a good idea while the heads are off.

If you took the main and rod caps off and found damage of any kind , you could get a single new rod/ main bearing set out the set in in place of the old and plastigage it to see if you are in tolerance. It's been my experience that as long as the grooves didn't catch your finger nail, it has a good chance of living. I've had to do this for a lot of customers. I worked a high volume shop on the poor side of town, so this came up a lot!

Like you said, it's probably fine based on what you've seen. Another thing to check that's cheap to replace is the timing chain. With the synchronizer sensor off, turn the crank by hand back and forth to see when the synchronizer just starts to move. What is acceptable, 5-10*? I'm on the ship, I don't have my books..... Someone know off the top of their head?

decipha
01-15-2015, 06:24 PM
my first supercoupes were a pair i bought from jersey

black 90 odo broke so no idea but I only put 9k miles on it and it spilt the crank
red 90 130k s&s reman engine, 8k miles and popped a headgasket

titanium 91 hg blew at 140k new hgs and aod went out at 145k, new 4r70w swap and engine locked up at 149k

black 90 -pulled engine for power build 190k going strong

blue 92 slave cylinder went out at 120k when i was 3hrs from home, then hg went 2 weeks later

Orange 93, hg blew at 119k

black 94 hg blew at 88k

purple 95 4r70w went out at 68k, then engine locked up at 74k, new engine with wiseco pistons lost junk gapless rings at 7k

I dont have good luck at all with supercoupes

S_Mazza
01-15-2015, 06:39 PM
Mine is the original engine as far as I know. HGs replaced by me around 170k. Still going strong at over 200k. No signs of trouble whatsoever.

Ira R.
01-16-2015, 03:52 PM
Let's see...... what is it now, three engines in 6 years? maybe about 1000 miles on each.....

Doesn't say much for longevity does it ;)

superpoop
01-16-2015, 05:06 PM
See, from almost everything I'm reading these things are absolute unreliable heaps.

Doesn't bode well considering how much needs spending on it.

Had my 98 cobra for 7 years and it's let me down once. Had the bird 6 days and blew the motor. Head gaskets are a prone failure, there are videos all over YouTube of them blown...

Anyone with anything good to say about these motors or is that it? Horror stories? :(

XR7 Dave
01-16-2015, 06:02 PM
People are happy to report bad experiences because misery loves company. For some reason it is also kinda cool in this club to denigrate the motors. However, the fact is that behind nearly every engine failure is a story of neglect, abuse, misuse, or misfortune or a all of the above. The motors are not prone to failure any more than any other pushrod Ford. In fact the 3.8L V6 is arguably the best pushrod motor Ford has built. It's not the most popular, but it's I think it just might be the best.

But if you are starting out doubting it's worth, then it's probably best to do something else because most likely you'll never believe in it anyway.

My personal experience is that my XR7 which I bought in it's production year (1990) never did fail other than head gaskets which is common with any and ALL forced induction motors. That motor saw over 200K miles, a LOT of drag racing, street racing, towing, and just plain idiot driving at HP levels ranging from stock to well over 400rwhp. But for any good testimony you'll find a bunch more negative ones so I guess you have to decide for yourself for your own reasons.

These motors don't cost that much either. Sure you can buy a lot more cheap Chinese parts to put in/on a 5.0L than you will a 3.8L, but if you build both motors using similar quality parts you will spend approximately the same money either way. It's more a matter of what you want than how much it costs.

superpoop
01-16-2015, 06:41 PM
A cars value to me isn't down to overall cost it's down to how long it lasts, how much you can build of it yourself. My belief is in all honesty, I will mess this up. I had a 2.3 fox mustang that had 125k on it when it died from rust. I then spent around 3000 buying parts, rebuilding axles, swapping sheet metal etc. day two of the build and a crack appeared in the screen. Paid another 400 for a new screen and it cracked that one too. All that money wasted. In total it was around $5300 when converted. Hence me wanting to junk this car and forget about it. It's my girlfriend that's the driving force behind it. She wants to learn, build and be rewarded for her labours. She feels it will make us stronger too.

I have every confidence in fords products. I used to work for them, own a crap ton of ford branded clothing, wallets etc. the doubt lies in my rookie building skills.

I would prefer an untouched motor but hey, they aren't around. This motor needs head gaskets and an oil pan gasket and it's good to go. But seeing as it's done 180k miles I figured bearings would help the longevity some.

1FSTBRD
01-16-2015, 08:16 PM
People are happy to report bad experiences because misery loves company. For some reason it is also kinda cool in this club to denigrate the motors. However, the fact is that behind nearly every engine failure is a story of neglect, abuse, misuse, or misfortune or a all of the above. The motors are not prone to failure any more than any other pushrod Ford. In fact the 3.8L V6 is arguably the best pushrod motor Ford has built. It's not the most popular, but it's I think it just might be the best.

But if you are starting out doubting it's worth, then it's probably best to do something else because most likely you'll never believe in it anyway.

My personal experience is that my XR7 which I bought in it's production year (1990) never did fail other than head gaskets which is common with any and ALL forced induction motors. That motor saw over 200K miles, a LOT of drag racing, street racing, towing, and just plain idiot driving at HP levels ranging from stock to well over 400rwhp. But for any good testimony you'll find a bunch more negative ones so I guess you have to decide for yourself for your own reasons.

These motors don't cost that much either. Sure you can buy a lot more cheap Chinese parts to put in/on a 5.0L than you will a 3.8L, but if you build both motors using similar quality parts you will spend approximately the same money either way. It's more a matter of what you want than how much it costs.

Some great points, Dave.

I also have to wonder in each individual case of where the engines have problems, whether 87 octane was used (and how often) without pulling the octane plug, and/ or how often coolant changes and oil changes were done. Those sorts of things will reduce the life of any engine, but the heat inherent in the SC motors will just kill it quicker than a non FI car.

I can see why auto manufacturers had largely grown wary of turbocharging/ supercharging cars, after the 80's/ early 90's. There's not the knowledge by most of the average customer base, which includes the maintenance of a different type of engine. Turbocharging and supercharging has made a comeback (with engineering that is designed to take more abuse from negligent owners), and is more efficient. But I can understand why the craze died down after the 80's, initially.

decipha
01-16-2015, 08:33 PM
I'll admit, I'm the hardest test driver god has ever created, throttle state is either on or off theres no such thought of part throttle existance in any of my personal cars, just speak of it and youe liable to catch a wrap to the throat

One thing I'll say about the supercoupes, Ive never had one fail without advanced noticed other than a slave cylinder failure

Jacob_Royer
01-16-2015, 09:17 PM
My five speed SC is bone stock and had the HG's replaced at 110k at the first sign of leakage by the previous owner. He did new o2's new water pump all new hoses had a valve job heads pressure tested and surfaced did it all right. I'm at 170k now drive it every day and it does not use a drop of ANY fluids and runs like a new car. However my auto 93 spun a rod bearing at 110k It was a one owner car when i bought it years ago and by all means looks alot better and has always been garaged since new. When i initially tore into that car i discovered that the heads had been replaced with reman's a year before i bought it. I'd say that they had a catostrophic HG failure which resulted in coolant in the oil and did dammage then. I've seen 5/6 SC's with spun #3 rod bearing shortly after HG failure. PO of my DD replaced HG at the first sign of steam out the exhaust and therfore its never had any issues! I still have the original balancer too knock on wood. Jeff Bratton has 300k and never been into his motor original balancer too! and he has been around 300rwhp for YEARS pretty tough engines IMO but you can't blow the HG's to the point of coolant going into the oil and expect it to live much longer.

KMT
01-16-2015, 09:27 PM
If it's just about head gaskets, there is a poll on year & trans type: http://www.sccoa.com/forums/showthread.php?60317-If-Head-Gasket-Blew-Request-Yr-and-Type-of-Tranny&highlight=head+gasket+poll

XB-70
01-17-2015, 12:18 AM
FWIW, I have yet to do a HG job in 25 years of having 9 different SCs and I do flog 'em but not as much like Dicepia I guess. :rolleyes:

The one without an engine I currently have came to my hands with a damaged block from the #4 piston breaking (detonation maybe) and snapping the rod in half and out through the side of the oil pan. However, when I pulled the heads they did not show any damage and head gaskets were complete and free of fissures.

My bomber mule, the '90, has over 130K and the entire drivetrain is untouched but for lots of mods added. Original radiator, water pump, clutch, HB, trans and and diff. It sees high boost 11-15 PSI consistently with a late blower, 36#, bigger MAF and TB, MP plenum and a very open exhaust to save the day. The original radiator still cools well and I am sure I have not had to do HG on it thanks to annual coolant flushes and new antifreeze. I plan on going 200K before she gives up on me. As DD stated, preventive maintenance (or lack of it with neglected driving in the heat) is what dooms these otherwise amazing V6 motors. Not the smoothest motor FORD has made but considering how it pulls like a truck, I'd say they are something special.

Cheers

S_Mazza
01-17-2015, 10:59 AM
I would prefer an untouched motor but hey, they aren't around. This motor needs head gaskets and an oil pan gasket and it's good to go. But seeing as it's done 180k miles I figured bearings would help the longevity some.

In your situation - since the motor will have to come out at least part way to do the oil pan gasket - and since head gaskets will be half as difficult with the motor out - you should strongly consider at least a refreshment of all bearings, including cam bearings, and valve train parts. New pistons may or may not be required, depending on compression test results.

MadMikeyL
01-17-2015, 02:26 PM
I've owned a number of SCs over the years, as well as 5.0 and 4.6 powered tbirds and other cars. I have also used all 3 powerplants in daily drivers, and blown engines in all 3. While the 5.0 and 4.6 do have better durability, the SC isn't bad in this department, just not quite as durable as the others. I suppose it shouldn't be any surprise that a supercharged V6 making 210-230hp in stock form isn't as durable as a naturally aspirated V8 making 200-205hp. I personally have had a 5.0 car and 2 4.6 cars with over 250K miles that the valve covers had never been off. I can't say that for the SCs. The highest mileage I ever had on an SC without anything engine-wise having been taken apart is 178K, and that was in an 89XR7 when it spun a rod bearing. That motor never popped a head gasket, and was beaten on daily for over 2 years when it finally failed, even with the spun the bearing, I was still able to drive it home over 300 miles with the engine knocking away, so it didn't even leave me stranded. Most bottom end failures on SCs that I have seen have been spun rod bearings, and I think the fact that the cars are supercharged puts more strain on those bearings, so even in a very well maintained car, that is likely to fail eventually. With that being said, I have seen stock bottom ends with over 200K on them, so you can't really call a spun bearing at that mileage a design fault or a weak point, it is just a wear item that will eventually need to be replaced. Head gaskets are more common on these cars than on other engines, but again you have a supercharged car, and I have seen a number of SCs, especially 94/95s, with over 200K miles on stock head gaskets, so they aren't guaranteed to fail, and I think as XR7Dave said, most failures can be attributed to neglect or abuse, or both. It really depends what you are looking for. If you just want a cheap reliable daily driver, I would say go for a 4.6 bird. They are cheaper, easier to maintain, easier to get parts for, and more durable, but they are nowhere near as fast or as fun, unless you spend a bunch of money on them, in which case their reliability goes down, just like the SCs. If you want something that will be a weekend car, a project, and will surprise a lot of people, then get an SC, take the time to rebuild the engine correctly, new head gaskets with ARP studs instead of the bolts, and keep up on the oil changes and coolant flushes, and you should be able to get 150K+ reliable miles out of it without a problem, which will take you a long time to rack up on a weekend only car.

superpoop
01-17-2015, 06:53 PM
See we already have the car, it's with us In England.

The motor was ran with oil which was last changed on the 6th December 2008. Unknown mileage at the point of change. I drove it 300 miles home with zero issues or noise, did around 100 miles on top to a buddies place for a little body repair, then drove it to get replacement oil and filter. It blew 18 miles from us buying oil and seized the motor. It wasn't until after that we realised the oil change date (written on the filter) and decided on a motor swap or full rebuild.

We have located a replacement motor in the US and are shipping it back, however it has 180k on the clock with apparently no problems whatsoever. Head gaskets and bottom end bearings including mains will be replaced, if anything is needed further than that then my girlfriend is giving up on it too. Car was free to us, but needs a total exterior overhaul. It's very solid underneath and straight, all interior electrical pieces work fine, as does all suspension. Although when these cars sell here for 1500 pounds, and it needs 3000 pounds worth of paint and bodywork, a new 300 pound windshield, new front upper A arms at 80 delivered, and a motor at 870 pounds to our door. Then to factor in magnaflux, head skim, new valve springs, new timing chain, cam bearings, porting the exhaust, bottom end bearings, head gasket, harmonic balancer... The list goes on forever, and none of it is cheap stuff. We are talking over 2000 in parts, machining and new tools to complete the job. That's doing all the work myself. And if it goes bang, which being fair here a lot of rebuilt engines listed above have exploded or otherwise broken again afterwards. Then we have to source a new motor and start again.

6250 is $9750 worth of repairs. I can buy a low mileage GT s197 for the same money. Or an f150 lightning.

See why it scares me even looking at this thing?

If however, you guys can say actually these things don't normally need doing, it's just for your own benefit, they will usually last many years with a bearing refresh, that would ease my mind a little. Infact it would give me a lot more confidence in the build, especially seeing as I now have an engine build manual, some plastigauge and a spare motor to play with. Machining is the whole reason we are sourcing a motor in the first place. It costs too much money in the UK. Crank regrind is 300 pounds, as near as makes no difference $470. Just for the crank!

MadMikeyL
01-17-2015, 08:56 PM
If the engine is rebuilt properly, there is no reason it shouldn't last you another 150K miles easily. With that being said, a proper rebuild does include some machine work. The heads at a minimum should be checked for straightness. The crank should also be measured, not just plastigauged. One thing I have found with every higher mileage SC engine I have taken apart is they wear out the cylinder bore faster than a 4.6 or 5.0, and so most likely will need to bore the block out and get new pistons and rings. If engine machining is that expensive there, and given that you are already planning to ship an engine from the US, I think you might be better off to have XR7Dave do all the machine work here, and sell you a package that you would then assemble over there, if he is willing to ship it overseas. That may be a way of saving money on the deal. Either way though, the problem is these cars simply don't have a lot of value, so by the time you do a proper rebuild, you have likely spent more than the car is worth. If this is purely a financial decision, then the answer is sell the car as is and buy something that you will be easily able to obtain parts for. If you love the car, then it is worth it to fix it, because being over in England, you likely aren't going to find another one. Another option for you may be to swap the engine out for a 5.0. I'm sure they are not quite as common over there as they are over here, but I would be very surprised if you couldn't get a complete running 5.0 already over there for cheaper than shipping an SC motor from here.

superpoop
01-17-2015, 10:45 PM
If the engine is rebuilt properly, there is no reason it shouldn't last you another 150K miles easily. With that being said, a proper rebuild does include some machine work. The heads at a minimum should be checked for straightness. The crank should also be measured, not just plastigauged. One thing I have found with every higher mileage SC engine I have taken apart is they wear out the cylinder bore faster than a 4.6 or 5.0, and so most likely will need to bore the block out and get new pistons and rings. If engine machining is that expensive there, and given that you are already planning to ship an engine from the US, I think you might be better off to have XR7Dave do all the machine work here, and sell you a package that you would then assemble over there, if he is willing to ship it overseas. That may be a way of saving money on the deal. Either way though, the problem is these cars simply don't have a lot of value, so by the time you do a proper rebuild, you have likely spent more than the car is worth. If this is purely a financial decision, then the answer is sell the car as is and buy something that you will be easily able to obtain parts for. If you love the car, then it is worth it to fix it, because being over in England, you likely aren't going to find another one. Another option for you may be to swap the engine out for a 5.0. I'm sure they are not quite as common over there as they are over here, but I would be very surprised if you couldn't get a complete running 5.0 already over there for cheaper than shipping an SC motor from here.


In terms of bore, I have been told two different stories now. Some are saying it has higher zinc than other newer blocks so it would more than likely not need any block work. The car was given to me, it has been driven 3 times including the detonation so I really do not care whether it ever moves again or not. Shipping and machine work are what's killing the funds. I can easily obtain anything from anywhere in the country it seems, but when you add all the small costs together you get a large one. For that large one I can own something else that has never had a blown motor and I have no question about the durability.

This forum, my experience with 3.8s in the sn95 mustangs, and my 6 days then explosion experience from the motor have completely destroyed any interest I had in rebuilding or ever driving this car again.

Under mileage the cylinder walls wear quickly, the head gaskets die on the regular, heads warp, and absolutely every part needs replacing or machine work doing. Or the other option which is buy a new rebuilt motor at 2500 dollars, ship it for another 600 due to insured value, then pay 15% duty on that total, then 20% tax on the total of motor + shipping + import duty.

Man I hate this car. Haha!

HwyStar
01-17-2015, 10:54 PM
Yes, these cars are maintenance intense. But, I think of it like the 6.0 PowerStroke. They are great when their working, drive beautifully, endless power. But, you have to do a bunch of updates and work arounds to make them reliable. They are complicated to work on too. Once you get it all done, you aren't likely to have any more trouble out of it.

I've learned now what to look for with these engines. Mud colored oil. If I drain the oil and it looks like mud, from fine bearing material I stop. Funny thing is, with other engines I've had them knocking and the crappy oil come out and was able to run them for a good long time as long as oil pressure was good. With 3.8, they just lock up. Don't know why.

S_Mazza
01-18-2015, 12:12 AM
This forum, my experience with 3.8s in the sn95 mustangs, and my 6 days then explosion experience from the motor have completely destroyed any interest I had in rebuilding or ever driving this car again.

Under mileage the cylinder walls wear quickly, the head gaskets die on the regular, heads warp, and absolutely every part needs replacing or machine work doing. Or the other option which is buy a new rebuilt motor at 2500 dollars, ship it for another 600 due to insured value, then pay 15% duty on that total, then 20% tax on the total of motor + shipping + import duty.

Man I hate this car. Haha!

You are asking a lot from a FREE CAR with UNKNOWN HISTORY.

That aside, if you told me that your only option to get a certain vehicle running again was to get a used engine shipped from across the sea, with 180,000 miles, sight unseen ... I would say you were rolling the dice. I don't care if it was a Ford Thunderbird, Honda Civic, Jaguar, or Rolls Royce, you are taking a chance. They're all made of metal. They all wear out.

superpoop
01-18-2015, 06:36 AM
You are asking a lot from a FREE CAR with UNKNOWN HISTORY.

That aside, if you told me that your only option to get a certain vehicle running again was to get a used engine shipped from across the sea, with 180,000 miles, sight unseen ... I would say you were rolling the dice. I don't care if it was a Ford Thunderbird, Honda Civic, Jaguar, or Rolls Royce, you are taking a chance. They're all made of metal. They all wear out.

The only reason it was free was due to the fact I paid 800 pounds for it from a buddy down in London. I was out of work at the time, but needed to get to Leeds for a job interview when the cobra failed inspection. It was the lesser of two evils. It did not get me to Leeds, it blew on the Saturday and the interview was Wednesday the week after.

My buddy who sold me the car found out that it died via Facebook and sent me the money back to fix the cobra. My girlfriend fronted the difference between tbird and cobra cost and The tbird has sat here since.

Car has full history. Previous owner put 800 miles on it since he bought it, it had full history before him.

On to this car, if it was something I could build by throwing bearings at it i would be a very happy guy! But seeing as it will need the crank, cylinder bores and potentially cam bearing work, along with head alignment, new timing chain, valve springs, valve seats etc.

Both myself and the previous owner were talking about it weeks after, he was saying my blown motor would not be worth building due to machine work labour, but according to what you guys have told me it's the same either way. So it's either a low mileage motor in it or nothing from a cost vs reliability perspective.

MadMikeyL
01-18-2015, 06:38 AM
I don't know anything about nickel content, all I know is I have taken apart 4 SC motors ranging from 87K miles to 178K miles, and at 87K there was barely a ridge at the top and I was able to get away without boring it out, but the other 3, which had 120K, 157K, and 178K, all would have required a re-bore if I wanted to re-use the block. On the other hand, I have taken apart several 5.0s and 4.6s with over 200K that showed absolutely no cylinder bore wear. Again, I don't think the 3.8SC is a bad engine at all, it is just generally a more expensive engine to rebuild. From the sounds of it though, you are not interested in the car, and are looking for a reason to justify not fixing it, so I would suggest selling it to someone who won't mind putting the time and money into it. If you do decide to fix it though, I think it would be a huge waste of money to buy an engine with that many miles and pay to ship it across the ocean, because by the time you take it all apart, it may need just as much machine work, if not more than your current seized engine. You have said that machine work is very expensive over there, so if you are going to ship an engine or parts from the U.S., you might as well ship already machined parts to save on that cost. Another option is to save on the shipping by simply rebuilding what you have. Another option is swap the engine out for a 5.0, and yet another option is selling the car and getting something else. But getting another engine that basically needs a complete rebuild, shipping it across the ocean, and then paying for all the necessary machine work is a ridiculous waste of time and money.

820
01-18-2015, 08:58 AM
Grow a pair and tell your girl friend fixing this P.O.S. aint going to happen. You dont want to do it so it will end badly, with possibly you two splitting up over a stupid car.

bowez
01-18-2015, 09:06 AM
There are a couple Brits, between here and TCCOA that may be interested in a parts car.

On my last motor I was able to get all parts from wholesale source (one time deal) and I spent probably close to if not over $1500 USD. I had to get a motor from a salvage yard and that was $800.

XR7 Dave
01-18-2015, 10:09 AM
Grow a pair and tell your girl friend fixing this P.O.S. aint going to happen. You dont want to do it so it will end badly, with possibly you two splitting up over a stupid car.

Amen to this. If you are having the types of discussions in your mind that you have posted here then please get rid of the car and get something that is made locally and has an abundance of part available on the cheap. It seems that with a Cobra and SC you are playing way out of your field.

For everyone else, these blocks are not a hard material comparatively speaking. I bore and hone them all the time.

I would never re-ring one of these blocks that has high mileage because the natural taper in the walls caused by the forced induction means that the new rings will not seal well, wear will be very accelerated, and the increased clearances will not sit well with the hypereutectic pistons. This is just an FYI for anyone reading this since I know the OP isn't going to rebuild his motor.

If you start out with a good running motor that just lost head gaskets or a bearing, you can fix that problem without ever bothering to do anything with the rings. They are probably sealing just fine, and as mentioned above, honing and installing new rings is just going to make things looser, not better. If you are having sealing problems, then it's already too loose and you are going to make things worse by honing and putting in new rings.

For anyone rebuilding and thinking about the "ridge" at the top of the cylinder, consider this, the entire hole used to be the same size, top to bottom. So now that there is a ridge at the top which you can catch your fingernail on, that means it is significantly worn to cause this. Stock clearance is about .0015", with .0035" being the wear limit. That means there is an allowable .002" wear factor which when spit between both sides of the bore that means .001" on each side. You can't catch your fingernail on .001". It is more typical that if you get a ridge and you say to yourself "hmm, I feel a ridge there," that there is more like .005" minimum ridge there which translates into .010" total clearance across the bore. The piston is literally flopping around in there at this point, and the fact is that at the bottom of the bore it's probably pretty close to tolerance which in turn means that the cylinder looks less like a cylinder and more like an upside down bell. So this means that your rings are going in-out at an extremely rapid rate as the engine runs and they can't possibly generate a good seal while they are doing this. On old parts that have been wearing together for 100K+ miles, they have all the right smooth spots in all the right places to where they are working together like this "ok", but if you put in new rings with sharp edges and their natural rough surfaces that need to wear in, they will basically kill the pistons and cylinder walls in the process.

It's just all bad.

Either bore it and put in new oversize pistons, or leave it alone. I have made nearly 500rwhp on 200K mile stock piston rings. If it ain't broke, don't fix it.

aroot1
01-18-2015, 12:33 PM
Amen to this. If you are having the types of discussions in your mind that you have posted here then please get rid of the car and get something that is made locally and has an abundance of part available on the cheap. It seems that with a Cobra and SC you are playing way out of your field.

For everyone else, these blocks are not a hard material comparatively speaking. I bore and hone them all the time.

I would never re-ring one of these blocks that has high mileage because the natural taper in the walls caused by the forced induction means that the new rings will not seal well, wear will be very accelerated, and the increased clearances will not sit well with the hypereutectic pistons. This is just an FYI for anyone reading this since I know the OP isn't going to rebuild his motor.

If you start out with a good running motor that just lost head gaskets or a bearing, you can fix that problem without ever bothering to do anything with the rings. They are probably sealing just fine, and as mentioned above, honing and installing new rings is just going to make things looser, not better. If you are having sealing problems, then it's already too loose and you are going to make things worse by honing and putting in new rings.

For anyone rebuilding and thinking about the "ridge" at the top of the cylinder, consider this, the entire hole used to be the same size, top to bottom. So now that there is a ridge at the top which you can catch your fingernail on, that means it is significantly worn to cause this. Stock clearance is about .0015", with .0035" being the wear limit. That means there is an allowable .002" wear factor which when spit between both sides of the bore that means .001" on each side. You can't catch your fingernail on .001". It is more typical that if you get a ridge and you say to yourself "hmm, I feel a ridge there," that there is more like .005" minimum ridge there which translates into .010" total clearance across the bore. The piston is literally flopping around in there at this point, and the fact is that at the bottom of the bore it's probably pretty close to tolerance which in turn means that the cylinder looks less like a cylinder and more like an upside down bell. So this means that your rings are going in-out at an extremely rapid rate as the engine runs and they can't possibly generate a good seal while they are doing this. On old parts that have been wearing together for 100K+ miles, they have all the right smooth spots in all the right places to where they are working together like this "ok", but if you put in new rings with sharp edges and their natural rough surfaces that need to wear in, they will basically kill the pistons and cylinder walls in the process.

It's just all bad.

Either bore it and put in new oversize pistons, or leave it alone. I have made nearly 500rwhp on 200K mile stock piston rings. If it ain't broke, don't fix it.



ARRRGGGH!!!! I read this almost exactly 12 hours AFTER running the ball stone hone thru the motor I'm freshening up! :mad:

Story of my life :rolleyes:

Adam

superpoop
01-18-2015, 04:21 PM
the list of cars i have owned include but not limited to

98 cobra
91 5.0 notchback,
91 LX 4 cyl,
98 crown victoria LX
superpoop.

on all except one of the above, general maintenance has been as far as it needs to go. none of these cars are available locally. the cobra is more difficult to obtain parts for. but it is also more reliable. there are three other supercoupes in the UK that i know of not counting mine. two of them are owned by the same person, and are sat outside his property with... you guessed it. blown motors.

the other one i havent seen since it was on ebay around the time i bought mine.

i buy these cars for a hobby, not as transport. but there is a limit to how much you can spend for zero gain. once bitten on the dead fox chassis.

the reason i am involved in this altogether is because my girlfriend will not let this car die. she also has a 1984 power ram short bed in need of a full restoration. she wants to restore this car because its cheaper option rather than to restore the ram. both will be restored regardless of whether i walk away from the deal or not.

i for one dont want her to bankrupt herself restoring a car that would be of dire reliability. we have talked about it today, there is absolutely no way of changing her mind. the new motor will get new bearings and reinstalled so she can use it. we then have time to do all the nessesary machine work to the motor that sits in it now. the car is now hers, but the repairs are split 50/50 between us both.

i thank you guys for all your help thus far, and apologise for my frustrations on the subject. i work hard for my money and hate to see it wasted. i hope you guys can appreciate this.

Neill

S_Mazza
01-19-2015, 12:55 PM
i for one dont want her to bankrupt herself restoring a car that would be of dire reliability. we have talked about it today, there is absolutely no way of changing her mind. the new motor will get new bearings and reinstalled so she can use it. we then have time to do all the nessesary machine work to the motor that sits in it now. the car is now hers, but the repairs are split 50/50 between us both.

i thank you guys for all your help thus far, and apologise for my frustrations on the subject. i work hard for my money and hate to see it wasted. i hope you guys can appreciate this.

Neill

Sounds like you have reached a decent compromise. I think there is a good chance that the used engine will last for a good while with new bearings. I just wouldn't bet my bottom dollar on it, was all I was trying to get across.

Rebuilding the old motor may cost less than you think if you find the right sources. In any case, you can at least enjoy the car for a while while you think about it.

TbirdSCFan
01-20-2015, 11:57 AM
White car OEM engine.. regular 5000 mile oil changes = 290,000 miles and still running strong. No blowby! :cool:
The car was driven normal, not raced, but not pampered either.

Note: The evidence that 3000 mile oil changes is a big pile of baloney is proven by the numbers on my white car.

gr8ghost
01-22-2015, 11:04 PM
Dude you almost never make money on cars. It's kinda the same with women. If it's a hobby and it's your mindset to make money you'll never really enjoy it. Cars cost money. Women cost money. The trick with both is to enjoy them for what they are. So enjoy the ride with her and learn how to work on cars together. Love it all and stop worrying about the ~~~~~~~~.
The only way around it with cars is if you are a good mechanic and someone off's a car to you to fix and you do inexpensively, so that you sell it for more than you have in it.

1FSTBRD
01-22-2015, 11:33 PM
If it's causing you this much agony, then it's time to get rid of the car. Parts here in North America (I live in Canada) are still fairly easy to find, but I can only imagine how costly it becomes where you live.

SC's are great cars, but very complicated and it was undoubtedly a learning experience from Ford, because their goal was to create a great driving/ handling car with lots of power, and good gas mileage......for a decent price that wasn't too expensive. They wanted to compete with BMW, but at an affordable price. That's a problem, right there. The problem with the triad of "excellent/ fast/ expensive" is that you can take two of those, but throw out the other. In Ford's case, they tried to forsake "expensive" in that scenario, and some of the reliability and R&D went down. In a relatively ominous omen, the guy that spearheaded the SC's development, got the axe from Ford for the SC going over budget and over the target weight.

In some ways, I kind of wonder if Ford may not have been better off continuing to develop and work on the Turbo Coupe engine......but the issue, I think, came from that people did complain that the engines were somewhat lacking in low end torque and throttle response in daily traffic and the turbo lag likely didn't help matters. The Roots styled design was a great idea to rectify the acceleration concerns, but the systems generated a lot of heat and posed reliability issues over the course of time (and of course, neglect). 12 psi and the insane low end torque that the cars put out are pretty ballsy, and in a lot of ways, i'm surprised that they last as long as they do without major issues.

It's kind of a no-win situation for Ford.

HwyStar
01-23-2015, 09:20 PM
Thats a good point. One of the other reasons I like these cars is that they are a challenge to me. People get pissed when they see my car sometimes. It sitting there running great, fast, doing what its supposed to. Some people say,"I hate those cars, why would you mess with one of those?" I tell them, the challenge makes them more interesting, and that they are just mad because their quitters.

1FSTBRD
01-24-2015, 12:38 PM
Thats a good point. One of the other reasons I like these cars is that they are a challenge to me. People get pissed when they see my car sometimes. It sitting there running great, fast, doing what its supposed to. Some people say,"I hate those cars, why would you mess with one of those?" I tell them, the challenge makes them more interesting, and that they are just mad because their quitters.

I agree! The cars definetely are a challenge. The spark plug change, alone, once one completes it (it took me 6 hours) feels like.......you've really defeated the odds, you know? Same thing with the V6 engines....i'm a 3.8 guy, and it's fairly rare, but you'll get some guys that write things off just because something "has to be a V8/ manual", etc. This is my 3.8 Mustang--fairly modified--with a 93 Bama race tune. For an auto 3.8, that is some pretty good acceleration on a N/A motor that has the stock heads/ cam (over 200,000 kms on the original engine!)--the shifts are super hard and although these are winter tires on the car on a colder October day, on a hot summer day, my 315 Nitto's still chirp on the shifts.

Again, I enjoy the challenge....


https://www.youtube.com/watch?v=EqZWzWSGCo8

chickencoupe
02-10-2016, 04:19 AM
I'll admit, I'm the hardest test driver god has ever created, throttle state is either on or off theres no such thought of part throttle existance in any of my personal cars, just speak of it and youe liable to catch a wrap to the throat

One thing I'll say about the supercoupes, Ive never had one fail without advanced noticed other than a slave cylinder failure

Hehehehahaha.

SuperCoupeDave
02-11-2016, 12:08 PM
Out of the SC's I've had in the past, they all blew head gaskets at 150k. Other than that they were almost flawless.

superpoop
02-15-2016, 04:27 PM
Update on the car.

Its still fk'd. Sat outside for well over a year now. We bought a replacement engine for it around march/April which we stored in the back of my girlfriends garage just before a full kitchen was thrown in last summer.

We have been looking for the motor for a month or so as it wasn't where we last left it. Her dad threw a tarp over it and wheeled it into a garden last June when he bought the kitchen. We found it behind all the firewood lay on a grass patch. It was still on the pallet but leaning forward pretty good. the front lower half of the crank pulley was embedded in the ground and has rusted to hell. Give me some good news, are the harmonic balancers balanced with the crank pulley? Please tell me they arent. I am hearing some saying they are and I will need both. We don't have that cash available. If they are totally separate then no biggie. I'll throw my old one on when this motor goes in.

Neill

MadMikeyL
02-15-2016, 05:58 PM
They are balanced together, however since the 3.8SC motor is neutral balanced, it isn't that critical. If you are having someone balance a rotating assembly, bring him the pulley, but if you are just swapping a stock motor for another stock motor, you can swap the pulleys out without having any issues.

JonS
02-15-2016, 06:58 PM
I hope you keep the SC. definitely keep the girlfriend.

superpoop
02-16-2016, 06:15 PM
Oh she's a keeper for sure.

The reason the repair of the tbird has taken so long is down to the fact she has sold her 84 ram late last year and bought herself a replacement 83 ram slant 6 instead. DVLA (UK DMV equivalent) has valued it at 4000. She paid 1000 for it, plus taxes at 770. Its currently in the process of registration.

The cobra has also been painted and I have since added some 03 cobra 17's. I had some noises from my rear end so recently rebuilt it and have some lower control arms waiting to go on too.

Its been a fun 12 months.

Time to concentrate properly on the SC. The motor will be wheeled in the garage tomorrow now we have space. I will be renewing all gaskets including headgaskets while the motor is out. it already has new plugs and wires so I don't run into that issue later when its installed in the car. also have a VSS ready to plug into the trans as the speedo has been moving around while the motor is running but car is stationary. It also needs to have the front upper control arms installed. I have arranged for the motor to be installed later this month. It then needs a screen and its almost ready.

ABS light is currently on, I'm used to sensors being at fault with the sn95 but apparently the tbird has a much more elaborate system. I'll have to dig into that.

There has been progress! Parts have been bought and now we are seeing some dry days I'll have an opportunity to get to it a little better.

Neill