3.1 LIM & RTV - does this look right? (pics/*UPDATE*)

[TurboSedan]

ok i installed the lower intake manifold on my 3.1 MPFI a few days ago and took pics of the area that i used black RTV on. this is the first time i've done a lower intake manifold gasket.....

does this look right?

http://www.turbosedan.com/cutlass/engine/DSC01491.JPG

http://www.turbosedan.com/cutlass/engine/DSC01492.JPG

[robby1870]

RE: 3.1 LIM & RTV - does this look right? (pics)

I usually use more than that. I coat almost all of the surface. Im not saying yours wont work, just telling what I do.

[TurboSedan]

yeah that's what i'm worried about while i was putting the RTV on i was cautious to not be too liberal with it, but after i had the LIM torqued down i noticed that there was actually a small gap between the block surface and the ends of the intake....i was under the impression that the LIM surface would be right up against the block surface...i didn't think there would be any gap there. it 'looks' like it will seal fine, but i wanted to get others opinion...

thanks Robby

[Rhedalert]

make it bigger. If nothing else, a little "higher" though it might be dried by now?

[TurboSedan]

ok i'm going to pull the LIM back off

kinda sucks i have to buy a new gasket now but it will be alot easier doing it on the engine stand than in the car. it would really suck to start it up the first time and have oil leaking everywhere. oh well, it will be easier the second time around.

thanks guys

[TurboSedan]

ok i just pulled the LIM back off and i'm glad i did. part of the RTV bead i laid down did not even look like it was 'flattened' by the LIM even though it was torqued properly to spec. i definately need to lay down a thicker/taller bead next time. easy to do, but sucks i wasted a perfectly good gasket. oh well, live and learn.

thanks again.

EDIT: btw, do the lower intake manifold bolts really need sealant on the threads? my Haynes manual says they do so i lightly coated the threads on all 8 bolts with white TFTE paste....

[bszopi]

The newest TSB for tightening says to get new bolts with thread sealer on there, or just use Loctite (I used the red I think) to make sure the bolts don't loosen.

[geoffinbc]

Yea use loctite. New bolts are bullshit. They dont even get tight enough to stretch so why replace them?

The bead should be 3/16 wide and tall.

[v6h.o.]

Yea use loctite. New bolts are bullshit. They dont even get tight enough to stretch so why replace them?

they are a torque to yeild bolt. We always replace them here at work. plus it saves us having to clean and reloc-tite the old ones.



That is waaaay too little RTV. Good thick bead. Like suggested you dont even have enough on there as per height let alone width.

[Rhedalert]

It can't be a torque to yield bolt. The 3x00 vertical manifold bolts are torqued to 89 lb/in and the ones going into the head are 18 lb/ft. When I did mine I went with loctite blue.

[TurboSedan]

damn i really need to get myself an FSM. my Haynes manual doesn't say anything about replacing the bolts.

the Haynes manual reads:

NOTE: Coat the bolt threads with pipe thread sealant.

that's why i used the TFTE paste. i'll clean them off and use red loc-tite when i reinstall the manifold though. the manual goes on to say:

Caution: To prevent oil leaks, tighten the verical bolts first to ensure that the lower manifold stays centered on the gaskets, then tighten the angled bolts.

torque spec for the 2.8/3.1 listed as:

Lower intake manifold-to-cylinder head bolts/nuts

2.8L and 3.1L

Step one................15 ft/lbs
Step two................24 ft/lbs

so i'm assuming i tighten the four vertical bolts to 15 ft/lbs, and then tighten the angled bolts to 15 ft/lbs. then tighten the vertical bolts to 24 ft/lbs and finally tighten the angled bolts to 24 ft/lbs.....is that right?

and damn....my torque wrench only goes down to 20 ft/lbs i guess i do have an in/lb torque wrench though....

thanks again for the help everyone.

[TurboSedan]

well i bought a new LIM gasket today, and got to work replacing it. re-adjusted valves, laid down the RTV and put the gasket in place. i cleaned the LIM bolts of TFTE paste and used red loc-tite on them instead. i cleaned off the old RTV and wiped all surfaces with a clean rag and Brakleen before installation. i tightened the 4 center bolts to 180 in/lbs, then the 4 outer bolts to 180 in/lbs, then the 4 center to 24 ft/lbs, then finally the outer bolts to 24 ft/lbs.

http://www.turbosedan.com/cutlass/engine/DSC01582.JPG

http://www.turbosedan.com/cutlass/engine/DSC01583.JPG

http://www.turbosedan.com/cutlass/engine/DSC01584.JPG

after torquing:

http://www.turbosedan.com/cutlass/engine/DSC01585.JPG

does this look like the right amount of RTV? i am confident it will seal this time...

[Juglenaut]

I would put a small beed around the coolant passages, but that just me.

[geoffinbc]

Yea your looking good. But you still could have used a little more. But I think you will be fine this time.

[Mars]

Wow, thanks for posting this. I am gonna do my LIM gaskets in march, and man, let me tell you, I was not gonna put that much on there. Now I know.