Big Leak trouble, Help! Video of oil leak

[cppursell]

Hey truckers,

I've been living with a bad oil leak on my 307 for a while now, at the front of the oil pan where it meets the timing cover. Last night I removed the oil pan by raising the engine, cleaned and scraped thoroughly, then installed a nice one-piece silicone gasket and tightened up the bolts not-too-snug. The dang engine leaks the same!

The under-belly of the beast...

Please watch this video and evaluate, Where is the leak coming from, out of the timing chain cover? Is the U-bend of the oil pan not snugging up (but it didn't leak this bad before)? Thanks for your help!

[truckdude239]

Depending on he pan it could be warped. But also there are 2 different gaskets a thin gasket and a thick gasket most 75 up use the thick gaskets as do most after market oil pan

[cppursell]

Okay, so the chrome pan is definitely aftermarket. I did notice that I can see an awful lot of the gasket in front. I didn't have an option to buy a "thick" gasket at the store, but should I just swap pans with an OEM one? I can re-use the gasket too.

[chiefcfd]

I have always had leaks with the chrome timing covers and oil pans. They never seem to be the right fit. I would change both of them for original styles.

[cppursell]

I found this thread, the 2nd post explains there's a different gasket for aftermarket oil pans. Should I get this gasket or a new old pan? http://forums.corvetteforum.com/c1-a...-at-front.html

[cppursell]

I'm off to buy the thick 34510 gasket now! I'm confident that's the problem!

[Russ.W.]

Originally Posted by cppursell

I'm off to buy the thick 34510 gasket now! I'm confident that's the problem!

Definitely the right choice and what I had to do with mine when changing pans.

The oil pan changed somewhere in the mid 70's I believe, and all aftermarket and repro pans are modeled after that later, wider ended pan.

The difference is slight ... probably be no more than 1/8" - but enough to cause dramas.

Here's the original on my '67 small block:




And here's the aftermarket:

[cppursell]

This gasket is a lot thicker, I can't wait to bang my fingers and get oily again!

[FRENCHBLUE72]

Hope the new pan gets her al sealed up..

[alsriv2]

Ive always had great success using Permatex Aviation sealant brushed onto the gasket surface before installing gasket. It sticks like glue and never hardens. It is also oil and detergent resistant so it will stay in place and seals like a champ.

[trac209]

The ultra thick gasket you have only fits a certain style of pan I tried to use one of those once and it was too thick to allow the pan to seal on the rails. Your vid is not working now so I can't see your pan.

[sprint_9]

It looks like the timing cover is bent or broke. If you look closely to the left side of the drip it looks like the entire gasket has a coat of oil on it that appears to me to be coming out from under the front cover. It is running down the gasket and dripping off of the corner of the gasket where it meets the pan lip.

[cppursell]

Well I installed the 34510-T gasket and it stopped the leak!! This gasket is much thicker on the front. After driving it 25 miles on errands, under inspection it hasn't dripped! I noticed a small oil buildup so that could be a small seepage but nothing to worry about any longer. Woohoo! Happy new year!!

[mrolds88]

Glad you got the leak stopped. One thing I noticed on the video was the harmonic balancer. It actually looks like the outer ring is loose. Would definitely check that thing over good.

[sprint_9]

Hmm must have been the video making the timing cover look suspect to me. In the picture you posted it looks great.

[alsriv2]

I never knew the difference in the pan shapes and the gasket requirements, guess I have been lucky enough that everything lined up and fit properly. Thanks for sharing your experiences with us and highlighting the fix.
Happy truckin'!

[cppursell]

This was a big lesson to learn, thanks for all y'all'ses help . Go Old Iron!