Author Topic: Oil coming out valve covers...  (Read 16838 times)

Offline Unofficial

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Oil coming out valve covers...
« on: September 09, 2010, 10:13:30 PM »
Lately I've been loosing a lot of oil out of my valve covers. I got new gaskets because they were leaking. No more leaks from where the gasket is, but I'm blowing a lot of oil out of the grommets, they fit fine but there's still oil all over the outside of the valve covers wherever there is a grommet. My oil breather is soaked with oil, even with a baffle underneath the grommet. The PCV valve is brand new, any ideas? It's a 350 tbi with a mild cam by the way.
1987 Custom Deluxe R10
350 TBI bored .040 over
700r4 with a Transgo shift kit
MSD ignition
Long tube headers w/ true duals
Upgraded sound system w/ subwoofer

Offline beastie_3

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Re: Oil coming out valve covers...
« Reply #1 on: September 10, 2010, 12:17:56 AM »
blow by?

Offline bake74

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Re: Oil coming out valve covers...
« Reply #2 on: September 10, 2010, 01:57:38 AM »
     x2 on the blow by.  Better take a look at your oil pressure...
#1: The easiest and most obvious solution to any problem is 99% of the time correct.
#2: There is no such thing as impossible, it just takes longer.
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Offline Unofficial

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Re: Oil coming out valve covers...
« Reply #3 on: September 10, 2010, 09:35:28 AM »
Well my oil gauge is messed up...It jumps around all over the place. When it's steady it's usually between 15-30psi. Sometimes when I come to a stop though the gauge will read at around zero, but I figured the gauge is just out of whack.

Can anyone go into more detail about the blow by? Is that when I have too much pressure in the crankcase? (Bad rings?)

This motor was completely rebuilt about 10k miles ago...
1987 Custom Deluxe R10
350 TBI bored .040 over
700r4 with a Transgo shift kit
MSD ignition
Long tube headers w/ true duals
Upgraded sound system w/ subwoofer

Offline 1980c10

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Re: Oil coming out valve covers...
« Reply #4 on: September 10, 2010, 02:13:45 PM »
Does your air filter have oil on it too?

Offline Unofficial

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Re: Oil coming out valve covers...
« Reply #5 on: September 10, 2010, 04:20:28 PM »
Does your air filter have oil on it too?

No oil whatsoever in the air filter
1987 Custom Deluxe R10
350 TBI bored .040 over
700r4 with a Transgo shift kit
MSD ignition
Long tube headers w/ true duals
Upgraded sound system w/ subwoofer

Offline 1980c10

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Re: Oil coming out valve covers...
« Reply #6 on: September 10, 2010, 09:34:22 PM »
I know you said your PCV valve is new; but re-check it anyway, check it in place with the engine running. Pull the PCV valve from its grommet and place your thumb over the PCV valve opening. You should feel it click. If the click sounds or feels mushy, replace it again.
Also check the line from the valve to be sure it isn't blocked or kinked.
Another way to test it is to remove it and shake the valve. If it's good, you’ll hear a solid clicking sound.

Offline Irish_Alley

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Re: Oil coming out valve covers...
« Reply #7 on: September 11, 2010, 01:03:17 AM »
im in the same boat but mine used to be only when I hit high rpms but now its all the time went to change gaskets pan and covers then I saw oil on the dip stick tube so now my truck is parked to I rebuild a 350 or build a 383
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

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Offline screamin86

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Re: Oil coming out valve covers...
« Reply #8 on: September 11, 2010, 01:13:34 AM »
Make sure the drain holes in the heads are not blocked a guy from work had that issue with his truck.
86 k10 lwb 4x4:350 .040 214/224 444/466 112lsa performer rpm 1406 lt's summit racing th350 2800stall
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86 ta:lm7 hot cam boltons

Offline Unofficial

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Re: Oil coming out valve covers...
« Reply #9 on: September 11, 2010, 12:15:11 PM »
The PCV valve is literally brand new. I shook it and there's a good click. And I just really doubt that I need an overhaul... Like I said, this engine was completely rebuilt about 10k miles ago! I guess I can check the drain holes like screamin86 said. I just find it odd that I'm getting oil dripping from the breather filter even when I have a baffle in the valve cover underneath it.
1987 Custom Deluxe R10
350 TBI bored .040 over
700r4 with a Transgo shift kit
MSD ignition
Long tube headers w/ true duals
Upgraded sound system w/ subwoofer

Offline TexasRed

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Re: Oil coming out valve covers...
« Reply #10 on: September 11, 2010, 01:24:19 PM »
Did you really over fill your crank case?

Offline Unofficial

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Re: Oil coming out valve covers...
« Reply #11 on: September 11, 2010, 02:13:55 PM »
Did you really over fill your crank case?

If I did overfill it, it wasn't by much at all. I guess I don't know how much it would take to leak out though.
1987 Custom Deluxe R10
350 TBI bored .040 over
700r4 with a Transgo shift kit
MSD ignition
Long tube headers w/ true duals
Upgraded sound system w/ subwoofer

Offline TexasRed

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Re: Oil coming out valve covers...
« Reply #12 on: September 11, 2010, 02:56:06 PM »
On a long shot, maybe your exhaust is plugged up and causing the exhaust to be pushed out past the rings. That would take a lot of blow by to get that kind of oil leak.

Offline Unofficial

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Re: Oil coming out valve covers...
« Reply #13 on: September 11, 2010, 03:20:45 PM »
On a long shot, maybe your exhaust is plugged up and causing the exhaust to be pushed out past the rings. That would take a lot of blow by to get that kind of oil leak.

I recently chopped off a big part of my exhaust... It was mandrel bent at a 90 degree angle coming out before the rear tires. But I didn't like the look after a while and I cut off the exhaust maybe a foot after the mufflers, could be more I don't remember exactly.
1987 Custom Deluxe R10
350 TBI bored .040 over
700r4 with a Transgo shift kit
MSD ignition
Long tube headers w/ true duals
Upgraded sound system w/ subwoofer

Offline VileZambonie

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Re: Oil coming out valve covers...
« Reply #14 on: September 11, 2010, 05:05:11 PM »
What kind of valve covers and breather do you have? If it's blow by you'll have a lot of smoke in the crankcase with it running.

http://www.summitracing.com/parts/MOR-68776
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