Author Topic: trying to confirm leak  (Read 4465 times)

Offline Low87

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trying to confirm leak
« on: March 05, 2012, 07:31:51 PM »
I'm losing big time oil, like a quart a week.  I know I'm burning some, but there hasn't been much of a leak.  Tracked down some traces to what looks like the head gasket, rear driver's side.  Here's a pic from the underside.  Can't get a good look from the top.  What do you guys think?


It will be about a month before I can do anything about it unfortunately.  Either just replace the gasket or go ahead with my engine swap.  Any ideas to tide me over?

Thanks.

Offline heavychevy91

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Re: trying to confirm leak
« Reply #1 on: March 05, 2012, 07:58:21 PM »
I would take a look at your valve cover gaskets. My .02

Offline bd

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Re: trying to confirm leak
« Reply #2 on: March 05, 2012, 08:45:32 PM »
The intake manifold rear valley seal, and/or an oil pressure switch/fitting at the back of the intake manifold, and/or a missing distributor gasket, and/or valve cover gasket(s) are the most likely source(s) of the leak(s) pictured.  However, if you were leaking a quart of oil per week you would have oil puddling under your vehicle.  If the picture shows your worst leak, most of your oil is blowing out the exhaust.  Are there any other oil tracks around the engine?
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline bake74

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Re: trying to confirm leak
« Reply #3 on: March 06, 2012, 05:57:34 AM »
     I agree with bd.  The other thing I would do is take off the valve cover to check torque on the head bolts and check the valve gasket and how it looks.  The valve gaskets can dry out and leak, but like bd said, a quart a week, you should have big time puddles unless you are mostly burning through it with your engine.
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Offline Blazin

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Re: trying to confirm leak
« Reply #4 on: March 06, 2012, 07:00:53 AM »
x2 on what bd said. No way thats a quart a week leak.
Some people are like Slinkies. Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs

Offline heavychevy91

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Re: trying to confirm leak
« Reply #5 on: March 06, 2012, 07:55:31 AM »
It was late when i posted. everything bd said as well. thanks.

Offline Low87

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Re: trying to confirm leak
« Reply #6 on: March 06, 2012, 04:47:11 PM »
Thanks guys.  It's definitely not puddling.  Little mark underneath, but not what I'd expect.  It blows smoke on start up, but not while running.  Exhaust is pretty foul smelling though, but I imagine that's another issue.  I'll pull the valve cover this weekend.

Offline bd

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Re: trying to confirm leak
« Reply #7 on: March 06, 2012, 05:32:06 PM »
If you decide to persue the oil consumption issue maybe this thread will be of some help...

http://forum.73-87chevytrucks.com/smforum/index.php/topic,22312.msg184287.html#msg184287
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline 1980c10

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Re: trying to confirm leak
« Reply #8 on: March 06, 2012, 10:22:35 PM »
When the engine is warm after the truck has been driven. With the truck running hold a peice of paper behind the tail pipe and the oil may show up on the paper if you have serious blow by.

Offline sbx22

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Re: trying to confirm leak
« Reply #9 on: March 06, 2012, 10:30:29 PM »
I had a leak pretty much that same location, it turned out to be where the oil pressure line is hooked up. Tighten that thing down just to make sure. Hard to describe, but on the fitting, there are two adjustment points. You'll see what I'm talking about, one smaller, one larger right on top of one another. I would try this before you take the valve cover off.

Offline Low87

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Re: trying to confirm leak
« Reply #10 on: March 07, 2012, 08:14:47 AM »
If you decide to persue the oil consumption issue maybe this thread will be of some help...

http://forum.73-87chevytrucks.com/smforum/index.php/topic,22312.msg184287.html#msg184287

ha!  Point taken.  Thanks again.