I have a problem with oil coming from the intake bolts under the carberator. Does anyone have a trick to stop this from happening?It is a 350 engine with an aluminum intake.
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I have a problem with oil coming from the intake bolts under the carberator. Does anyone have a trick to stop this from happening?It is a 350 engine with an aluminum intake.
Sounds like you have warped intake manifold. You need a thicker intake gasket or if that doesn't work you'll have to have the intake milled.
The manifold may or may not be warped. But, oil coming through the bolt holes does indicate a lack of good seal between the intake and the oil galley. A warped manifold is one possibility. Bad intake gaskets are another. You're going to have to pull the manifold. However, before having the manifold milled, I would get a good set of intake gaskets - the ones with the silicone beads around the ports - and install them.
Ed, listen to what Denny said. However, I would reccommend using liquid "thread sealant" rather than RTV on the bolt treads. If you do this to one bolt at a time, you won't have to remove the intake nor install new gaskets.
If the manifold was warped, you would probably have huge lean misfires on a few cylinders.
I guess I booted that one . . .
Thanks for all the suggestions. I think I'll try the thread sealant first and if that don't work I'll take the intake off and try different gaskets.
henry, whats what you call getting voted down, but i dont belive you can have a intake gasket or intake warped so bad oil will come past it and not have a vac. leak. i dont think so. i never heard of oil coming up pass the intake bolts eather. if you dont have a vac. leak i would be looking at the valve cover gaskets or blow-by. :HMMM: :LOL: :LOL:Quote:
Originally posted by Henry Rifle
I guess I booted that one . . .
Welcome to the club Henry.....we all shank 'em once in a while
I have a Eldebrock Air Gap with the raised runners, and a valley pan made into it & it leaks like a sive if I don't get it tightened down right & keep a check on it. I have to re-tighten it about every 6 weeks or it will leak around the front seal & oil will blow back under the carb. I think it over expands at the valley, and causes the rubber seal to leak. I have tried Loc-tite, rtv blue, bubble gum, and it still does it.
[QUOTE]Originally posted by hambiskit
I have a Eldebrock Air Gap with the raised runners, and a valley pan made into it & it leaks like a sive if I don't get it tightened down right & keep a check on it. I have to re-tighten it about every 6 weeks or it will leak around the front seal & oil will blow back under the carb. I think it over expands at the valley, and causes the rubber seal to leak. I have tried Loc-tite, rtv blue, bubble gum, and it still does it. [/QUOT
they will leak in the corners, there is on vac. there. but i cant see one leaking oil from the bolts under the carb and still run good. i got to see that. :HMMM: :LOL: :LOL:
Well, maybe I didn't explain the intake right, when I said raised runners- i mean raised up seperate from the valley pan. You can stick your hand under the carb. & wiggle your fingers. That's where the oil gathers- never said it leaks from the bolts under the carb( as in the ones that hold down the carb) but it will leak from the intake bolts, as well as front & rear valley pan seals, and still run.
Quote:
Originally posted by hambiskit
I have a Eldebrock Air Gap with the raised runners, and a valley pan made into it & it leaks like a sive if I don't get it tightened down right & keep a check on it. I have to re-tighten it about every 6 weeks or it will leak around the front seal & oil will blow back under the carb. I think it over expands at the valley, and causes the rubber seal to leak. I have tried Loc-tite, rtv blue, bubble gum, and it still does it.
take the rubber seal out, dont use it. then use the red or black, put the sealer on both sides and it should fix it. :D
Sometimes I feel like I'm running uphill on banana peals...I was just saying that it can be warped if it's not kept tight while it's hot, and then go back to shape when it cools, only showing that it leaks from the oil it leaves behind.
Thanks for the advise guy's - but I took it off & threw it in the trash, and got a Victor.......cured the problem.
Quote:
Originally posted by hambiskit
Well, maybe I didn't explain the intake right, when I said raised runners- i mean raised up seperate from the valley pan. You can stick your hand under the carb. & wiggle your fingers. That's where the oil gathers- never said it leaks from the bolts under the carb( as in the ones that hold down the carb) but it will leak from the intake bolts, as well as front & rear valley pan seals, and still run.
i was talking about the first post and i didnt say it wouldnt run i said it wouldnt run good because you'll should have a vac leak, if oil can get passed the intake gasket then vac can to. air will go places that oil wont. :)
ED JONES
I have a problem with oil coming from the intake bolts under the carberator. Does anyone have a trick to stop this from happening?It is a 350 engine with an aluminum intake.
Your right Lt-1, and yup Denny- sometimes a step up is the best cure.....lol
really didnt mean to get you up set over the intake hambiskit just talking :cool:Quote:
Originally posted by hambiskit
Your right Lt-1, and yup Denny- sometimes a step up is the best cure.....lol
I am fine Lt-1, can't see anything but learning from you my friend. Don't you worry about upseting me, sometimes I have a hard time explaining myself......I'm not a thin skined candy a** that can't take a lesson from anyone, and when I fire hot I don't sugar it , no offense taken at all......I get frustrated with myself that's all.
i wish i could express myself better, my spelling is so bad i have to pick and choose my words, so sometimes the way it comes out it dont make any sense or sound like im being short when im not. i found out one thing when i came on here. that i didnt know much about motors, you, tech and some of the other guys really know you stuff about what cam and heads to use for certain things. i really never got into that. :DQuote:
Originally posted by hambiskit
I am fine Lt-1, can't see anything but learning from you my friend. Don't you worry about upseting me, sometimes I have a hard time explaining myself......I'm not a thin skined candy a** that can't take a lesson from anyone, and when I fire hot I don't sugar it , no offense taken at all......I get frustrated with myself that's all.
Ed I'm the first guy who "booted" this thread for which I apologise, but I had the same problem on my sb and when it heated up and cooled back down I attributed it to a warped intake. Everyone who said this wasn't possible were correct as you would be running pretty lean. See even an old guy like me learns. Thanks guys for the imput.
Hate to be thread hack but this has be dead for awhile.
I dont have oil leaking, my question is do i put Anti-Seize on the intake and valve cover bolts? someone told me i should put locktight but im guessing thats false because of the heat involved.
Hey thanks for helpng a beginner out.
on the intake small amount of sealer on intake threads RTV or non harding sealer. on valve cover s you would not want a thread locker on valve covers there is on need less your going studs then some guys lock the studs in the head only. there is threads lockers and sleeve retaining compounds that can take 400 and some to 3000FQuote:
Originally Posted by mercado
excessive crankcase pressure will push the oil vapors from the valley up the threads. i use ss bolts and anti seize so they dont seal well. i use ss washers and thick orings that fit tight on the bolt. these seal it when tight . the oring will actually squeeze into the bolt hole in the intake.
if you just coat the threads with a sealer that stops the wicking i use ss bolts as well in many of my engine builds . the oil wicks up the threads with no sealer.... sbc has open holes not a blind thread holes only on the out side intake bolts of the heads on sbc and most all heads are open in the valley to hot oil coming off push rods as well as some are open to the push rod holes oil can lay in and some drain back from heads as you have ahot EX cross over as well on some heads and in time with out sealer fines its way out. sealer fills the root part of the thread s stopping it from ever getting up to the head of the bolt or washer . sealer will lube the threads very well and will seal it just fine . if blind hole then a very thin coat of oil . every one as there own way that works but ss or plane coated steel bolt with a zinc coating there is realy no need for anti seize less it in bad weather.salt.or SS steel on SS steel were the bolt and the head is the same metal make up you will have threads seize up
Why has no one suggested to check the PCV system? Check your PCV valve and the vent to make sure they are not plugged. Too much crankcase pressure will force oil out of bolt holes around oil pans, valve covers and intakes. If you a running at high RPM's most of the time you may need a vacu-pan system as the PCV system becomes ineffective at low vacuum conditions.
I know this is an old thread but it seemed the obvious was missed. This may help someone in the future.
i would say that you will push up the oil stick and vent from there and oil will blow out , vacu pans will not work on the street SO you will push oil out the seals front and rear you will vent thru the dip stick tube . oil filler cap may be wet to . before you pushing oil thru intake bolts so i would say nothing was missed ...? ... he did not say any thing about has oil pan or leaking oil as the engine will find away to vent it self .sounded more like a no thread sealer on intake boltsQuote:
Originally Posted by Two8tyThree
remember that there are 2 bolt angles used on sbc manifold to head---
my 4.3 V6 in my pinto pushes oil up thru the intake bolts .. why have pressure there
you do not . if you have pressure there you will have pressure in the valve covers .oil pan . timing cover :3dSMILE: seal the intake bolts thats stops the oil wicking the intake bolts :DQuote:
Originally Posted by HOSS429
Agreed vacu pans are for high rpm low vacuum as stated. Just mentioned to cover all bases. Not street driven engines.Quote:
Originally Posted by pat mccarthy
If the pcv is not working properly have seen the oil work through the threads of bolt holes. Once oil enters a bolt hole with a bolt in it there is a gap between the hole thread and the bolt thread unless it has sealer on it. Hydro static tension will hold the oil in the thread gap and any pressure ever so slight will work the oil up the thread.
If the pcv is working the negative pressure will draw the oil down the thread.
This was covered in a 2nd year class in mechanical engineering.
well hot oil will find it way thru the root of the theads . BUT sealer stops this over 20+ years building engines :3dSMILE:. .you run a vac pan on the street and it will vent out the dip stick long before oil wicks out the intake bolts .thats not 2 year class thats many years building race. street EX and headers . as for the roping of oil out of a engine i do know abit about this as a guy thats used open beathers on very big bbcs and work on a crank case vent system on a 526 bbc in a air boat that was a leaning class i took about 13 years ago:HMMM: if neg psi pvc and working right your saying its going to wick out the head of the bolt on the intake ? it is sucking . if plug then pos psi and i would think the hot oil will rope the bolt threads and leak out intake BUT like said other spots will show first as a engine builder and engine machinist i see guys buy new valve cover with no spot for beathers or PCV and not use any PVC or breathers and have oil getting pushed out .but thread sealer stops it any way you want to look at this .but i am just a dumb mich hill billy .i could be all way wrong on this right hearQuote:
Originally Posted by Two8tyThree
Agreed thread sealer stops this. And Pat your are definitely NOT as you quoted a "dumb mich hillbilly", you have a superb reputation which I much admire. I have read many of your posts and have learnt a lot from you. It is aways good to keep an open mind. Thanks for your reply.