Need help finding Oil Leak
Thread Starter
Instructor
Joined: Mar 2004
Posts: 207
Likes: 1
From: Minneapolis MN
Need help finding Oil Leak
I thought I had found the source of the oil leak in my '91 when I replaced the oil pressure switch. The strange thing about this leak is that it doesn't happen all the time. There isn't any oil on the ground when the vehicle just sits but when you start it up, oil that has accumulated (somewhere) around the converter is splashed to the ground in a 12" wide pattern from the spinning of the converter. In the picture below, the area has just been cleaned so I tried to mark the points where I usually see oil.
I would appreciate any ideas or suggestions on locating the source of this leak. Thanks.
I would appreciate any ideas or suggestions on locating the source of this leak. Thanks.
Last edited by harleyclassic; Aug 11, 2004 at 07:07 AM.
Instructor
Joined: Aug 2002
Posts: 198
Likes: 0
From: Yucaipa CA
Have you eliminated the rear joint between your intake manifold and your engine block "china wall"? I just completed my second R&R of my intake manifold ('90 L98) and the joint has finally stopped leaking. The first time I failed to apply sufficient RTV and it leaked like a champ but only when the engine was running at higher than speeds. 
Drifting
Joined: Nov 2002
Posts: 1,905
Likes: 1
From: 2003 Points Champ Great Lakes Corvette Challenge; 2006/2007 Winner MSD True Street
I had some troubles last year chasing down a small oil leak myself.
Real PITA!
Anyway, what Kevin at HP performance did was place some special additive to the oil (from GM I think) that glows under black light.
You drive around for a while bring it back, put it up on the lift and go over with a black light.
We found the locatiopn!
My two cents.
Matt383
Real PITA!
Anyway, what Kevin at HP performance did was place some special additive to the oil (from GM I think) that glows under black light.
You drive around for a while bring it back, put it up on the lift and go over with a black light.
We found the locatiopn!
My two cents.
Matt383
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
I too recently cured a very elusive oil leak by resealing the intake base.
The dye & black light should do the job of isolating the soruce though.
You might check some common soruces like:
-oil pressure switche & sender at top rear of block
-oil temp sender under block near oil filter
-dip stick tube at engine boss
-oil pan gasket seal
-rear main bearing
The dye & black light should do the job of isolating the soruce though.
You might check some common soruces like:
-oil pressure switche & sender at top rear of block
-oil temp sender under block near oil filter
-dip stick tube at engine boss
-oil pan gasket seal
-rear main bearing
Team Owner
Joined: Jul 2004
Posts: 28,472
Likes: 3,290
From: Hartford WI
You must pressuire clean the engine then go add some oil dye which is advailable at almost any decent auto parts store. Look with a black light. Also check your PCV. If it is blocked, crank case pressure could build up and blow oil out of even a good seal. That goes from compression because if it leaks past the rings, well, you get the picture.
