TBI intake manifold redo advice please.

[SkyHighColorado]

I replaced my 1994 TBI 5.7 intake manifold gaskets about 10k ago and I have some issues I need help with. Okay so first off I used fel-pro gasket kit and the rtv supplied in the kit for the valley front and rear seals. I also put a bead of rtv around the coolant passages on the gasket.

So, my issues are: My front and rear valleys are seeping/leaking oil. Recently I noticed I have coolant coming up from the second to last manifold bolt on passenger side right by the heater hose fitting. I am 100% sure its not the heater hose fitting leaking because I fixed that problem for good a while back. and I notice a small mount of oil coming up from the front driver side bolt.

I don't really have a problem doing this again this weekend, I just want to make sure I do it right next time. I had a hard time setting the distributor last time so I am seeking some advice on how to mark its position to make it easier to get running after.

After I put the rtv beads on the valleys and the gasket ports how long should I allow for it to set up before setting the manifold back on? how long do I need to let it sit for before torqueing the bolts? what is the correct sequence of torqueing them? how long should I wait before running the engine after its all done?

Should I use thread sealant on all the manifold bolts or just some of them?

I think those are all my questions for now. Thanks for the help!

 

[TylerZ281500]

i usually mark the dist in two places both there the rotor sits and mark the inside base and also the manifold and distributo and make two small marks on there, i always torque right after i put the gaskets on so the rtv dries while crushed. i have never used thread sealant on bolts unless they are reused alot i tend to go buy the new stainless 12 point bolts though. second question would be is how long ago was your torque wrench serviced? could be a cause but unlikely, just throwing that out there, ive put on an intake and tightened them by guessing before and it did fine, was a side of the road job using what we had. make sure your surfaces are uber clean as well, i like to use a nylon air brush to clean the surfaces then i follow that up with some denatured alcohol.

as for sequence i know there is one but i usually go inside out, so like middle bolt on one side opposing one across from it on otherside like a shoelace. probably not how its suppose to be but its never steered me wrong.

 

[98_k1500]

Paint thinner works really good to get the oil off so the RTV will stick. Be prepared to use hell and high water to get it off next time tho, that RTV will be stuck like a *****, but it won't leak.

 

[TylerZ281500]

Paint thinner works really good to get the oil off so the RTV will stick. Be prepared to use hell and high water to get it off next time tho, that RTV will be stuck like a *****, but it won't leak.

denatured alocohol, paint thinner, lacquer thinner all works lol

 

[98_k1500]

Don't use carb or brake cleaner. They evaporate so fast that they can leave condensation behind, resulting in a leak.

 

[SkyHighColorado]

Just checked the bolts... They came a little loose. Can I just re torque ?

 

[98_k1500]

May stop the gaskets leaking, not going to stop the RTV on the ends.

 

[michael hurd]

If you plan on using an RTV, clean the surfaces well, I use Lacquer Thinner and a 2 rag system. Lintless rags are preferred here. One wet to wipe, a dry one to wipe the wet residue.

I like putting the intake on immediately after RTV is laid down with no time to waste. You need to apply a nice even bead without stopping on both end rails. You may want to use a threadlocker on the bolts to keep them tight. Engines that have seen high rpm on a constant basis seem to have an issue with the intake manifold bolts loosening from time to time. I have used blue loctite in the past.

I would not use RTV around the ports, a couple of dabs of Permatex#2 will hold the gaskets from sliding down into the RTV when you drop the manifold on. Tighten immediately, working from the center out. Use a torque wrench to tighten them after snugging them down lightly with a ratchet.

 

[SkyHighColorado]

man I did everything you guys have said the first time around. If I am getting coolant coming up from the bolt next to the heater hose then the fel pro has failed correct? I don't see how the hell else coolant can come up through the threads on that bolt. would sealing the bolt threads do anything or just make it worse?

 

[TylerZ281500]

did you try to clean out the threads, dont use a tap youll make the wholes bigger maybe it didnt torque properly due to some debris. but i feel ya ive had random spurts of coolant come through bolt holes for now reason just tiny amounts never resolved it but always concluded i was never burning it off or mixing fluids.