Side of Intake Leaking Oil

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Re: Side of Intake Leaking Oil

Post by RD_Racing »

R.Olds wrote: Fri Apr 13, 2018 12:32 pm I would guess the gasket is wicking oil....seen it many times.
Is that due to a assembly or tolerance issue?
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Re: Side of Intake Leaking Oil

Post by R.Olds »

Edelbrock and Mr Gasket intake gaskets are the ones I have seen do this on several different engines.
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Re: Side of Intake Leaking Oil

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RD_Racing wrote: Fri Apr 13, 2018 9:53 am
BOOT wrote: Fri Apr 13, 2018 12:12 am Did you use sealer on those intake bolts?
The intake holes in the heads are blind holes so no need for any sealant.
You posative? I know a lot of alum heads they are not blind on the center bolts and from this pic(idk what version you but I'll guess they are all the same) it looks like they are most likely thru holes. https://precisionraceengines.com/produc ... der-heads/
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Re: Side of Intake Leaking Oil

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BOOT wrote: Fri Apr 13, 2018 4:45 pm
RD_Racing wrote: Fri Apr 13, 2018 9:53 am
BOOT wrote: Fri Apr 13, 2018 12:12 am Did you use sealer on those intake bolts?
The intake holes in the heads are blind holes so no need for any sealant.
You posative? I know a lot of alum heads they are not blind on the center bolts and from this pic(idk what version you but I'll guess they are all the same) it looks like they are most likely thru holes. https://precisionraceengines.com/produc ... der-heads/
Your right, I went back through my assembly pictures and some of the holes do go through but if you look close at the base of the bolts (in the picture I posted), you can see the permatex.. Its been months since I put the long block together and just forgot, sorry..
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Re: Side of Intake Leaking Oil

Post by shoedoos »

can you run a feeler gauge down between the gaskets and the intake/head? If so, tweek the bolts a little further and recheck with the feeler gauges...
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Re: Side of Intake Leaking Oil

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If its an edelbrock intake the intake flange will be cut wrong, usually .01 variance with the larger gap at the bottom of the ports,, could contribute to your plug fouling problem, did you check this, did you check head intake angle, should be 80*, if not when you pull it off mic the gaskets top to bottom, search and you shall find
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Re: Side of Intake Leaking Oil

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zums wrote: Fri Apr 13, 2018 6:45 pm If its an edelbrock intake the intake flange will be cut wrong, usually .01 variance with the larger gap at the bottom of the ports,, could contribute to your plug fouling problem, did you check this, did you check head intake angle, should be 80*, if not when you pull it off mic the gaskets top to bottom, search and you shall find
Tom

I had this problem with three diff eddy intakes.

Also should be noted torque sequence, some skip it on simpler things like intakes.
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Re: Side of Intake Leaking Oil

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zums wrote: Fri Apr 13, 2018 6:45 pm If its an edelbrock intake the intake flange will be cut wrong, usually .01 variance with the larger gap at the bottom of the ports,, could contribute to your plug fouling problem, did you check this, did you check head intake angle, should be 80*, if not when you pull it off mic the gaskets top to bottom, search and you shall find
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But in the last 15-20 years I have not seen an Edelbrock intake that did not need some angle correction as well as the intake port flanges that did not need to be machined thinner to correctly align the ports and make it fit the bolt holes centered.
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Re: Side of Intake Leaking Oil

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zums wrote: Fri Apr 13, 2018 6:45 pm If its an edelbrock intake the intake flange will be cut wrong, usually .01 variance with the larger gap at the bottom of the ports,, could contribute to your plug fouling problem, did you check this, did you check head intake angle, should be 80*, if not when you pull it off mic the gaskets top to bottom, search and you shall find
Tom
Yes, it's fine if the bottom gap is say 0.010" smaller as that imparts a wedging action to the joint, but the reverse is bad.
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Re: Side of Intake Leaking Oil

Post by Sparksalot »

Your photo of the parts sitting without a gasket is what I frequently find with all aftermarket parts. The right side of the manifold as shown is clearly not matched to the head. I always check this and correct it as required.

Belts and suspenders never hurt either. After machining to correct geometry and fit use Hylomar on the gasket and be done with it without any sort of concern.

The replies regarding manifold bolts intruding into oil spaces are important too. It's often overlooked in the heat of getting the job done but should be addressed at assembly. I've seen it missed too many times to count.
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Re: Side of Intake Leaking Oil

Post by Belgian1979 »

Put sealant on the intake bolts.
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Re: Side of Intake Leaking Oil

Post by RD_Racing »

I put some pressure to the crankcase through the dipstick tube after plugging the valve cover breather holes and there was no air weepage anywhere and it held the pressure too..
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Re: Side of Intake Leaking Oil

Post by RD_Racing »

Sparksalot wrote: Sat Apr 14, 2018 3:19 am Your photo of the parts sitting without a gasket is what I frequently find with all aftermarket parts. The right side of the manifold as shown is clearly not matched to the head. I always check this and correct it as required.
I agree the match on the one side isn't perfect but with the intake centered and the gaskets in place that gap will be split to both sides, which reduces that gap 50% and I would think the gaskets should easily cover that?

As mentioned in my above post, I also pressurized the crankcase last night and it held the pressure with no air weepage anywhere..
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Re: Side of Intake Leaking Oil

Post by geraldtson »

You mentioned a valve cover breather evac system. Have seen the typical Moroso/ Milodon breather evac systems pump pressure directly back into engine even when installed exactly as directed in open exhaust. Ended up with slow pesky leaks had me scratching my head for sometime thinking i had installed a system to keep this from happening when the system was the problem! Finally pulled hose off at valve cover end while engine running and found it was causing my problem pumping pressure back into engine.I quit using them, no problems! This was on circle track engine which gave leaks a little more time to develop but diagnosing problem was simple and immediate. This may not apply to your application but diagnoses was simple and immediate.
Last edited by geraldtson on Sun Apr 15, 2018 9:30 pm, edited 1 time in total.
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Re: Side of Intake Leaking Oil

Post by MadBill »

That could only happen if one or both check valves were leaking.. :-k
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