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micksix
08-28-2004, 11:31 PM
Greetings,

I'm putting my 93 SC back together after the hg's blew. I'm a little confused about the torque spec for the intake manifold. I have both a Haynes and a Chilton manual. They both state that the torque is a 2 step- 8 ft lbs, then 11 ft lbs. I'm curious if this is a typo. The non-supercharged are called out in a 3 step sequence finishing up at 24 ft lbs. Can anyone tell which is correct for the Supercoupe? Thanks!

ThunderDave
08-28-2004, 11:47 PM
When I did my HGs, I torqued them to 11 foot lbs. Are yopu using the old bolts? I did na dthey really didn't feel tight at 11. Someone had posted on here that when they use their old intake bolts, they torque them to 20 foot lbs. Ill, be doing injectors soon and might retorque mine then.

David

micksix
08-28-2004, 11:50 PM
When I did my HGs, I torqued them to 11 foot lbs. Are yopu using the old bolts? I did na dthey really didn't feel tight at 11. Someone had posted on here that when they use their old intake bolts, they torque them to 20 foot lbs. Ill, be doing injectors soon and might retorque mine then.

David
No, I bought new ones. It just seemed like a light torque and the manuals are clear as mud :D

ThunderDave
08-28-2004, 11:53 PM
I think the guy that posted that was getting at the bolts stretch when torqued, like head bolts, so 11 foot lbs on a stretched bolt won't be as tight as a new bolt would be.

David

micksix
08-28-2004, 11:58 PM
I think the guy that posted that was getting at the bolts stretch when torqued, like head bolts, so 11 foot lbs on a stretched bolt won't be as tight as a new bolt would be.

David

OK, I get that. So is 11 ft lbs the accurate torque spec for those bolts?

TBone95
08-29-2004, 12:03 AM
I just did mine today, the Ford manual calls for 13 and then 16 ft lbs. They are not torque to yield.

ThunderDave
08-29-2004, 12:06 AM
I just did mine today, the Ford manual calls for 13 and then 16 ft lbs. They are not torque to yield.


That sounds more reasonable, Haynes must be wrong.


David

micksix
08-29-2004, 12:09 AM
I just did mine today, the Ford manual calls for 13 and then 16 ft lbs. They are not torque to yield.

Thanks Tbone95, Do you happen to know off the top of your head if there was a seperate range for the non-SC model engine?

ss_scuba
08-29-2004, 05:25 AM
Actually...the Haynes manual is correct. I just redid my intake manifold gaskets, and was kind of surprised when I went through the shop manual and found that the SC specs were 11lb/ft final torque while the N/A were 22lb/ft. I went with the N/A specs when I bolted everything together and so far it's been pretty good.

That and using Fel-Pro gaskets rather than the Ford ones, I don't think I'll be using Ford gaskets too much anymore. Fel-Pro makes a far superior gasket, both in material and design.

TBone95
08-29-2004, 07:32 PM
In the official Ford manual I have both the NA and SC torque values appear to be the same.

XR7 Dave
08-29-2004, 07:37 PM
Actually...the Haynes manual is correct. I just redid my intake manifold gaskets, and was kind of surprised when I went through the shop manual and found that the SC specs were 11lb/ft final torque while the N/A were 22lb/ft. I went with the N/A specs when I bolted everything together and so far it's been pretty good.

That and using Fel-Pro gaskets rather than the Ford ones, I don't think I'll be using Ford gaskets too much anymore. Fel-Pro makes a far superior gasket, both in material and design.

Felpro makes the Ford gaskets.

XR7 Dave
08-29-2004, 07:42 PM
I have always torqued mine to 20ftlbs. Some people have had issues with vacuum leaks when torqued to only 11lbs. If there is anything in the threads at all I assure you that 11 is not enough. If the gaskets are leaking, then retorquing will not fix the problem. Once oil other contaminants get in there they can't be retorqued. David, I would plan on replacing the manifold gaskets when you do the injectors. That may be part of your problem.

ThunderDave
08-30-2004, 06:55 AM
I have always torqued mine to 20ftlbs. Some people have had issues with vacuum leaks when torqued to only 11lbs. If there is anything in the threads at all I assure you that 11 is not enough. If the gaskets are leaking, then retorquing will not fix the problem. Once oil other contaminants get in there they can't be retorqued. David, I would plan on replacing the manifold gaskets when you do the injectors. That may be part of your problem.


Dave, that had crossed my mind, believe me. If those injectors ever get here, I'll do that. I'm gonna go over it again and check for vacuum leaks. We are getting pounded by rain from Gaston, so I'll don't know if I'll get to work on it today or not, hope I can.

David

TBone95
08-30-2004, 09:31 AM
If there is anything in the threads at all...

Dave,

Do you use thread sealer on the intake manifold bolts? I noticed a note to use it when looking up the info for this thread. Unfortunately it was in the corner of the page where I didn't see it and the step by step instructions only mentioned oiling the bolts. I'm thinking now that I will have to go back and redo it, I'm hoping I can get away with taking one bolt out at a time and sealing it without having to take the manifold off and mess with the gaskets again.

-Travis

micksix
08-30-2004, 09:57 AM
Dave,

Do you use thread sealer on the intake manifold bolts?

Hey Travis,

I used sealer on the shoulder of the bolts when I re-installed mine. The machine shop had recommended that to me when I picked up my heads. I also went with the 20 ft lb torque - Thanks Dave.

-Clay

XR7 Dave
08-30-2004, 01:03 PM
You don't have to use sealer. The bolts protrude down into the lifter valley area, so the threads are exposed to oil. This has not been shown to be a problem. On the 8 bolts that are next to the water passages, often times there is weeping between the water passage and the bolt holes past the gasket resulting in the bolts getting corroded. Use of some gasket dressing in those areas will eliminitate that problem. Other than that, there really is no need for sealant on the bolts.

I do always use anti-seize any time I'm going into aluminum with a bolt.

edspringer
08-30-2004, 02:05 PM
I'm going to replace the 94 SC gaskets soon. I'm glad i read this. I have a rough idle problem and a constant whistle at idle. I tried the starting fluid test but could not get to the entire intake. I bought the SC with 73,000 miles and it had a new long block installed at 65,000. I have found a lot of little things wrong with the install; the biggest was a loose crank bolt that drove me nuts for about 8 weeks. That's another story.

Question: What sealer do you guys use for the intake end seals? I was going to use HI-TEMP RTV. Any better sealers?

Thanks for the info!

Ed Springer

90 Black XR7 5-speed: 70mm TB, Fresh Air Intake, '94 Supercharger, 5% SC Pulley, Raised SC Top, I/C Fan, Underdrive Pulleys, 190 l/h Fuel Pump, 36# Injectors, Headers, Magnaflow Muffler (no cats) with stock resoantors, 3:27 Gears, Ripper Shifter, 73 CL MAF, Magnacore Wires, NGK Iridium Plugs and Rear Spring Air Bags.

94 Red SC Auto: 70mm TB, Fresh Air Intake, Stock 90 SC Pulley, Raised SC Top, I/C Fan, Underdrive Pulleys, 190 l/h Fuel Pump, 38# Injectors, Headers, Raven Muffler (no cats) with stock resoantors, 3:73 Gears, 73 CL MAF, Magnacore Wires, NGK Iridium Plugs, TRANSGO Shift Kit, ProTorque 2500 Stall TC, Haydon Auxiliary Transmission Cooler, Tokico Struts & Shocks, American Racing 17 Sniper Wheels, Michelin Pilot Sport A/S Tires and 235 RWHP with 315 Lbs.Ft. Torque.

David Neibert
08-30-2004, 02:24 PM
Question: What sealer do you guys use for the intake end seals? I was going to use HI-TEMP RTV. Any better sealers?

I use the Ford intake manifold rubber gaskets and a healthy bead of Black Permatex RTV for the ends of the manifold. I'm also a big fan of the special Permatex gray water pump and tstat sealer that comes in a little tube, for around the water jackets on each end of the manifold. For the intake to head gaskets, the Felpros are the best. Unfortunatly, I can't use them because my heads are ported too large and I have to use handmade gaskets instead.

I also use a small dab of Copper RTV on all the intake manifold bolts. And anything that doesn't have sealer on it already, gets sprayed with Permatex Copper gasket sealer.

David

keisers1001
08-30-2004, 02:35 PM
I sometimes regret reading some of these posts....it makes makes me second guess the work that I have already done...I guess that is a good thing. I too agree that 11 ft-lbf sounded like a little low. I was thinking that I would retorque them to around 16 ft-lbf, but I am concerned that the rtv sealer I put in the corners will lose their shape and begin to leak since it has already set.

One thing that I noticed is that I had to go around the tightenig sequence about 4-5 times before all of the bolts were reading at 11 ft-lbf due to the fact that as you tighten the current bolt, the previous bolt will lose it's clamp load. I am on the fence on this one (looking to put the engine in by thursday).

John

edspringer
08-30-2004, 07:21 PM
I use the Ford intake manifold rubber gaskets and a healthy bead of Black Permatex RTV for the ends of the manifold. I'm also a big fan of the special Permatex gray water pump and tstat sealer that comes in a little tube, for around the water jackets on each end of the manifold. For the intake to head gaskets, the Felpros are the best. Unfortunatly, I can't use them because my heads are ported too large and I have to use handmade gaskets instead.

I also use a small dab of Copper RTV on all the intake manifold bolts. And anything that doesn't have sealer on it already, gets sprayed with Permatex Copper gasket sealer.

David

Thanks for the gouge on the right sealer!

Ed Springer

David Neibert
08-30-2004, 11:06 PM
Thanks for the gouge on the right sealer!

Ed,

I don't understand what you mean by gouge...I was just agreeing with your choice of sealers. I only mentioned Permatex because I have tried other brands and they did work as well.

David

XR7 Dave
08-31-2004, 08:27 AM
The whole "bolt loosening as you torque" thing is what prompted me initially to increase the torque on all the bolts. I found it was not possible (for me) to get an actual 11 ftlbs on all the bolts. Every time you torque one, the next one would loosen. The fact is that with a large aluminum part like that you don't want to clamp it so tight that you warp the flange. However, you don't want them to leak and you have to be able to achieve even torque across the surface or they will do just that.

I found that at 18-20 ftlbs, you can get it even if you do it in about 4 steps and then recheck your work afterward. I have also begun the practice of tapping the threads, wire brushing the bolts, reaming the intake bolt holes and applying anti seize to the bolts before assembly so as to get all the bolts to install as smoothly as possible. Any torque wasted on bad friction will result in reduced clamping force.

I wouldn't worry about distorting the silicone after its dry. The shape is not going to change significantly, you are just going to be putting some "insurance" on the torque. If the bolts went in smoothly, you are already tightened down all the way, you are just going to be putting a little extra tension on the bolts.

edspringer
08-31-2004, 02:55 PM
Ed,

I don't understand what you mean by gouge...I was just agreeing with your choice of sealers. I only mentioned Permatex because I have tried other brands and they did work as well.

David


David........the word "gouge" is a word we in the aviation community use sometimes for "info".

ED