intake plenum gasket?

sgleshot · Jun 14, 2011

ok i have a small bit of oil seeping from around my intake plenums, where they bolt to the head, it looks like they are just sealed up with some grey rtv, is there an actual gasket that should go in there? of is it just a matter of smashing some more rtv on it and let it set up?

rat49f6 · Jun 14, 2011

just rtv
shouldnt be oil coming out of them though they only flow air

02BigD · Jun 14, 2011

The head has to be oil free for the RTV to set properly.

Tom S · Jun 14, 2011

That is a special grey RTV from Ford or IH that is the best RTV ever. Most guys call it grey death. I seriously doubt more on the outside edge will seal it. I also would not be sure that oil means it is leaking but it could be. If one of the other guys does not post up a part number for the grey death I can find it.

ITUKMOR · Jun 14, 2011

If it is leaking take the time to fix it right or you will hate your life as it gets worse. Completely remove the plenum from the truck and clean it completely. Then make sure you brake clean the crap out of it and the head to make sure it is as clean as you can possibly get it. RTV or gasket maker is crap and again if you use it you will hate life. Purchase a tube of "GREY" from International or Ford. Yes it will be pricey but it is worth it. Once you have the grey on, quickly tighten the plenum bolts to spec before the sealant starts to set up and won't compress properly. Let it setup overnight before you go beating on it. If you take your time and do it right you will only have to do it once. If you shortcut anywhere you will just be doing it all over again.

(edit) Oil coming out of the plenum is normal as the crankcase vents into the intake which in turn runs through the entire intercooler piping and into the plenums. The part number from International is 1830858C1

rat49f6 · Jun 14, 2011

ITUKMOR said:
If it is leaking take the time to fix it right or you will hate your life as it gets worse. Completely remove the plenum from the truck and clean it completely. Then make sure you brake clean the crap out of it and the head to make sure it is as clean as you can possibly get it. RTV or gasket maker is crap and again if you use it you will hate life. Purchase a tube of "GREY" from International or Ford. Yes it will be pricey but it is worth it. Once you have the grey on, quickly tighten the plenum bolts to spec before the sealant starts to set up and won't compress properly. Let it setup overnight before you go beating on it. If you take your time and do it right you will only have to do it once. If you shortcut anywhere you will just be doing it all over again.

(edit) Oil coming out of the plenum is normal as the crankcase vents into the intake which in turn runs through the entire intercooler piping and into the plenums. The part number from International is 1830858C1

good point did the ccv mod at 50k so never had that issue

sgleshot · Jun 14, 2011

cool thanks, ya the lower rear bolt on the pass side was a little loose, took a good .25 turn to tighten it down. I gotta pull the van turbo in the next week or so to rebuild it so ill just get after the plenum then. And yes the ccv is still venting into the intake. Its not dumping oil but it is seeping just enough to run down the seam where the head meets the block, to the back of the motor and down the pass side of the motor, behind the starter. Maybe a drop or two a day, but enough to drive me insane!!!

sgleshot · Jun 14, 2011

Tom S said:
That is a special grey RTV from Ford or IH that is the best RTV ever. Most guys call it grey death. I seriously doubt more on the outside edge will seal it. I also would not be sure that oil means it is leaking but it could be. If one of the other guys does not post up a part number for the grey death I can find it.

I anticipated on pullin it apart to re-seal. I've got a tube of the grey, and theres no doubt that its gnarly stuff.

neverkickn · Jun 14, 2011

Are you sure that you dont have oil leaking from around the boots? I had that happen on mine before I did the ccv mod and it would run down the head like you described. A boost leak detector will tell you for sure if the plenum boots are leaking.

sgleshot · Jun 14, 2011

neverkickn said:
Are you sure that you dont have oil leaking from around the boots? I had that happen on mine before I did the ccv mod and it would run down the head like you described. A boost leak detector will tell you for sure if the plenum boots are leaking.

positive, wiped all them down with a clean white towel, dry as can be. Id be very surprised if snugging down the bolt that wasnt tight stops the seeping, but ive seen crazier sh!t happen.

SkySki Jason · Jun 15, 2011

Boost leak detector and some soapy water will tell ya if its still leaking there.

SkySki Jason · Jun 15, 2011

That Motorcraft TA31 sealant is killer stuff!! :thumbup:

http://www.riffraffdiesel.com/mm5/m...RRD&Product_Code=TA-31&Category_Code=F731-OEM

sgleshot · Jun 15, 2011

SkySki Jason said:
Boost leak detector and some soapy water will tell ya if its still leaking there.

now thats crafty!!!

rat49f6 · Jun 15, 2011

man that boost leak detector seems familiar

lincolnlocker · Jun 15, 2011

plenums are a pita, make for dam sure they are clean and not one bit of oil on them not even a fingerprint!!! had to do mine twice cuz they weren't clean...