Catastrophic Oil Leak on C2

[Jeffery F.]

After about 2 years and nearly 1,000 miles driven, my brother and I decided to change the oil in my '66 L79 engine. It still has the original canister / cartridge style oil filter. Drained the oil, removed the canister and filter without issues. Installed the new filter (WIX 51143), O-ring (square-cut) gasket that came with the filter, added a little grease to the block and gasket to retain the position of the gasket in the block and tightened to proper torque. Checked for gaps, tightness, secure fit. Added 5 quarts of high-zinc 10W-30 oil. Started the engine right up, backed it off the race ramps to take it for a test spin and OOOOHHH NOOOOOO! Oil was gushing out from the top of the canister, spraying everywhere. A terrible mess to say the least. What did we do wrong / what could have caused this major leak? Obviously there wasn't a proper seal at the canister and block, but what happened? This car has recently Top Flighted and has now become a driver so I am seriously considering installing an adaptor plate (should I also add an anti-drain-back valve??) and a spin-on oil filter. What manufacturer makes the best adaptor plates? Which oil filter to use (WIX 51060, PF-25)? I appreciate any advice or helpful solutions.

[Mark E.]

Re: Catastrophic Oil Leak on C2

Did you remove the old gasket?

[Duke W.]

Re: Catastrophic Oil Leak on C2

In my experience the ONLY WAY to replace that gasket is to remove the two machine screws that hold the bypass valve housing to the block, remove the old gasket, carefully inspect that all remnants of the old gasket are removed, then add a little grease to hold the new gasket in place, and install the bypass valve housing.

I replace the gasket every other oil filter change and never had an oil leak.

It's common to find multiple gaskets and two or more will often cause a major leak. Bubba was there.

There is no need for any kind of gasket between the oil bypass valve housing and block, but there are reports that '67 models, only, had one, for a reason unknown to me.

When starting a car after an oil or oil/filter change is to watch the oil pressure gage (or light) immediately on start up to make sure pressure comes up and prefilling the oil filter will make it happen faster, then immediately check under the car for leaks, or have a helper do that while you watch the pressure gage or light.

Duke

[Joe L.]

Re: Catastrophic Oil Leak on C2

In my experience the ONLY WAY to replace that gasket is to remove the two machine screws that hold the bypass valve housing to the block, remove the old gasket, carefully inspect that all remnants of the old gasket are removed, then add a little grease to hold the new gasket in place, and install the bypass valve housing.

I replace the gasket every other oil filter change and never had an oil leak.


It's common to find multiple gaskets and two or more will often cause a major leak. Bubba was there.

There is no need for any kind of gasket between the oil bypass valve housing and block, but there are reports that '67 models, only, had one, for a reason unknown to me.

When starting a car after an oil or oil/filter change is to watch the oil pressure gage (or light) immediately on start up to make sure pressure comes up and prefilling the oil filter will make it happen faster, then immediately check under the car for leaks, or have a helper do that while you watch the pressure gage or light.

Duke

Duke-----


Yes, the canister gasket is almost always the leak source when it's installed improperly or without removal of the old gasket.

By the way, the 1967-only gasket between the bypass valve and the block, GM #3903322, was used. It was actually also once available in SERVICE but was discontinued without supercession in July, 1981. I wonder how many of these things they ever sold?

[Jeffery F.]

Re: Catastrophic Oil Leak on C2

Yes. Absolutely.

[Paul H.]

Re: Catastrophic Oil Leak on C2

The gasket dropping down or being kinked will cause a leak. I always run a flat blade screw driver around the seating area after removal of the old gasket to be sure there is no remnant of the old gasket in there.
Sometimes when you are tightening up the cannister to mate with the top it can be crooked and misaligned. Be attentive to how straight it is by looking at it's distance from the bellhousing.

[John F.]

Re: Catastrophic Oil Leak on C2

Unless the gasket has been in there forever, mine usually falls right out with the use of an old ice pick. A little grease or Vasoline will hold the new one in. Go all the way around slowly with a small screwdriver to seat the new one. Prefill the filter with about a half quart of oil. Slowly start the bolt to start the threads, then push up on the canister and hold it. Do not spin it on. As you are it holding up tighten the bolt with a socket wrench. Easy peasy then torque to 20-25 ft/lbs and you are good to go. Once you do it a few times you can do it by feel w/o a torque wrench.

[Patrick H.]

Re: Catastrophic Oil Leak on C2

I just did this yesterday.

I found that I had to "wiggle" the canister a bit to get it square on the gasket and get a good seat.
In addition, after running the engine for a while I had to re-tighten the bolt about half a turn, as we had a small seepage from the bottom. All OK after that.

And why manufacturers are going back to this type of filter system is beyond me.

[Mark E.]

Re: Catastrophic Oil Leak on C2

And why manufacturers are going back to this type of filter system is beyond me.

It is messier but one advantage is you can inspect the filter media without cutting it open.

[Joe L.]

Re: Catastrophic Oil Leak on C2

And why manufacturers are going back to this type of filter system is beyond me.

Patrick-------

Probably an effort to be "green". It's difficult to separate the metallic components (recyclable) from the filter material (essentially non recyclable) which results in the entire spin-on filter ending up in hazardous waste landfills. So, eliminate the metallic components and only the filter material gets landfilled.

[Patrick H.]

Re: Catastrophic Oil Leak on C2

Patrick-------

Probably an effort to be "green". It's difficult to separate the metallic components (recyclable) from the filter material (essentially non recyclable) which results in the entire spin-on filter ending up in hazardous waste landfills. So, eliminate the metallic components and only the filter material gets landfilled.

But, I go through a lot more paper towels, etc to clean up after using one of these.
My daughters have a similar style, though plastic shell, on their Jettas. Getting the tiny gasket lined up isn't any easier on cars built today than it was 50 years ago.

[Joe L.]

Re: Catastrophic Oil Leak on C2

But, I go through a lot more paper towels, etc to clean up after using one of these.
My daughters have a similar style, though plastic shell, on their Jettas. Getting the tiny gasket lined up isn't any easier on cars built today than it was 50 years ago.

Patrick------


You don't expect "green" to make sense, do you? It's often the mantra of folks that don't have the ability to see or understand practicality or "ancillary" effects.

[Bob K.]

Re: Catastrophic Oil Leak on C2

Guessing the old gasket was still in place

[George J.]

Re: Catastrophic Oil Leak on C2

But, I go through a lot more paper towels, etc to clean up after using one of these.
My daughters have a similar style, though plastic shell, on their Jettas. Getting the tiny gasket lined up isn't any easier on cars built today than it was 50 years ago.

Patrick, some are easier, and if they design them to be vertical, there is almost no mess. My 1998 BMW M3 is great. It has a whole housing and you just remove the top and take the old filter element out. Not sure why there are so many bad designs for this. You would think everyone would copy a good design, and that would then be the new standard.

George

[Gary S.]

Re: Catastrophic Oil Leak on C2

Did you resolve your issue?