Need 2nd Opinion. HG??

Thomas A

Registered User
It's been a few years since I have really worked on an SC motor, so I'd like a 2nd opinion on this. I was getting ready to change the valve cover gaskets and do some other general maintenance items on my XR7, when I found this on the back side of the covers:

http://www.adenracing.com/Cougar/XR7_Valvecovers.JPG

That seems like an awful lot of moisture to me. The car seemed to run good, but I only drove it around the house and let it idle since I bought the car as it needs the brake master cylinder replaced, so I never actually took it down the road. The car had sat for a year or so before I bought it. I'm thinking I need to just continue downward and pull the heads and change the head gaskets. What do you guys think?

Thomas
 
That doesnt mean 100% you have a headgasket issue however that is a sure sign of condensation collection on the top of the covers.
 
Well, I did some more looking into it, and it seems it time to do the HG's. I drained the oil, and it was a very nice looking brown. Looked like milk chocolate. YUM!! I then pulled off the intake manifold and found signs of moisture in the lifter valley, so at the very least there was an intake manifold leak, although at this point, I'm just going to go ahead and pull the heads and take care of it. The car has 113K on it, and has never had anything apart on it. The plug wires are even still the originals.

Thomas
 
I've never replaced bearings before, so I have no clue how to do that. I was hoping to get away with just changing the head gaskets and flushing a lot of oil through it and calling it good. I've done that before and been ok, but I know that is not the best way to do it.

I'll get ahold of you Doug. I may need some help on this one. Do you think just replacing the rod bearings will be enough?

Thomas
 
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I've never replaced bearings before, so I have no clue how to do that. I was hoping to get away with just changing the head gaskets and flushing a lot of oil through it and calling it good. I've done that before and been ok, but I know that is not the best way to do it.

I'll get ahold of you Doug. I may need some help on this one. Do you think just replacing the rod bearings will be enough?

Thomas

I was hoping to just change head gaskets as well once I blew mine. Now Im running Doug's short block ;)


Ken
 
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With half your mileage, my front cam bearing is definately worn. Did main bearings on a 400 for a Bronco once. It's easy using plastigauge.
 
any coolant in the oil usually will damage the bearings. You wont see it right away but a few thousand miles down the road they will come back to haunt you.

Thomas Just let me know when you have the motor pulled and we can get together..

Doug
 
hrrmm.... I really don't feel like pulling the motor all the way out. If I do that, I should replace the front timing cover seal, front and rear main seals, cam bearings, main bearings, rod bearings, etc. At that point I'm pretty much rebuilding it, which I don't care to do.

I know it's not the best way, but I've had success with just flushing a lot of oil through the motor and not worrying about the bearings.

Thomas
 
Thomas,

Almost certainly the bearings on that motor started worn. If someone has been just topping up the coolant and fooling themselves before selling to you, I'd have to say the bearings are really close to completely shot. You could do a PH test of the oil you pull out of it, but I'm guessing it is highly acidic. That will pit the bearings.

You could just drop the k-member and pull the pan that way, then get at the bearings to check them. On the other hand you might get lucky. You could do the head gaskets, run your oil through it, then monitor oil pressure. The worn bearings should show low oil pressure. Perhaps telling you if you need to pull the bottom end.
 
With 113,000 miles anything is a possability. However if I had to change my bearings everytime I'd blown a headgasket on my small block when I was running juice I;d be a poor man.

Chances ARE AT 113,000 miles it needs refreshing regardless. The cheap way out is to do the gaskets, say a lil prayer and start her up.
 
If you have coolant in the oil, you need to change the bearings. It is as simple as that. The bearings may not be knocking now, but it will be soon enough. No matter what you do, it is just a matter of time. The one I did most recently, needed a short block after a few thousand miles (think it made it 3K).

Chris
 
Yeah I got posible problems too.

I used that blue liquid over the radiator fill neck to detect leaky HG's, I got plenty of small bubles which slowed and stoped after 10 min but it didnt change the blue to yellow:confused:. I have had several times where I pull off the oil fill cap and it just a little milky oil on the cap or sometimes its thick and chunky all down the filler neck. Then the next time after a long drive it will be spotless. It did use coolant but I found that to be a leak in my custom 3 piece lower return hose as I have a full LX radiator. I does have a slight lower end knock (only in N or park at 1K-1100 rpm)but that could be that bad drivers side motor mount ( with the hood up changing thru drive and reverse u can see the sc to intercooler pipe raise and lower 1 1/2 inches just ideling with my foot on the brake) or maybe its got a bad balancer as i do watch the idler arm for the main serpentine belt bounce around some. No milky liquid in my oil, mo unsual white smoke out the exhaust except for the first time I fried up that LX v8 exhaust i modded on, boy there must have been a lot of oil in those cats, looked like a huge burnout:rolleyes: exhaust will have a sooty resdiue on the ground after idleing for 10-15 min, maybe a but rich. Changed the oil 3 times since may especially since the 20-50 was too thick at 15 degrees, after it cooled in my collector pan i funneled it into milk jugs, like pouring cold syrup. I've had my 89 blow the hg's and a spun bearing before. This is just different on my 94
 
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I can guarentee you that with what I saw on those covers you will not make close to one thousand miles and you are going to start knocking after you let go of ths gas one day.I never say any antifreeze in my wifes 94's oil and I got her back together ran great for three hundred miles and knock knock knock.
 
I can guarentee you that with what I saw on those covers you will not make close to one thousand miles and you are going to start knocking after you let go of ths gas one day.I never say any antifreeze in my wifes 94's oil and I got her back together ran great for three hundred miles and knock knock knock.
Should we make a wager on that? I did head gaskets in a Thunderbird that was a 10x worse than this one, and have been driving it for the past 3 years, and have put thousands of miles on it without any issues.

Thomas
 
Thomas,

I wouldn't worry about it so much. Do what I did, throw a bag of sand in the oil and let the sand soak up the coolant in the oil. Drive it for about 3K miles and then change the oil again. All that sand should be at the bottom of your oil pan and you can just use a shop vacuum to suck it out. Replace with fresh oil and you are good to go for another 100K-200K.
 
Ahhh, yeah, of course! The oil pan has some grime in it anyway. That sand should polish it up and let the oil flow better!

Thomas
 
I perfer metal shavings to clean the system out. You can collected them via magnets in your oil filter..Make sure however to wait untill your oil pressure is at zero before you drain oil as to not waste a filter.

On another note. It is still beyond me that a rebuild would be deemed a necesity after a blown head gasket. As if the 3.8 is so very different then any other internal combustion engine.

Theoretically we would love to rebuild a motor after any mishap in which potential engine damage may have occured, no? Afterall there is always a chance ancillary damage has occured (especially with a high mile motor). But how time or cost effective is that for most do it yourselfers?

But well see eventually how this one turned out:O)
 
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