sbf oil leak problem. OT

Posting for a friend. Yes, there are some people that live so far out they have no internet. Sorry for the long post, but trying to give complete info. There have been several discussions of BBF rear main type leaks

Helping a friend work on his race engine. We have an oil leak we can't figure out. Looking for any ideas as this is a first.

421 ci sbf. Ford Racing 9.5" deck race block. C302B heads. 4.040 X 4.100 stroke. Cleveland size mains. Eagle 4340 crank. Block is new, crank is used. This is his "spare" engine" to be used while his 438 sbf #1 engine is rebuilt. Crank was in another 351W block that had to be replaced due to crack in main webbing near #2 main. Was causing funky oil pressure when it was torn down and crack found. Machine shop checked all crank journals and magnafluxed it before reusing it.

The engine was started and broken in on a test stand with no issues. Ran it the first weekend of racing and it ran well for the heat with no issues. Couple of days after the first race he was tuning it in the shop when it started a pretty substantial oil leak near the rear main area. It also started to leak trans fluid. Trans is a complete JW Ultra setup.

Pulled the trans and found the balance weight missing from the converter. Replaced the trans seal and rear main seal (1 pc seal) Took the converter to PTC to get the weight replaced. They fixed it and also said the converter was "warped", but they fixed it. Flexplate is a JW Wheel. Almost new, had been run w no issues for 10-12 race weekends. Put the trans back in. Fired up. No leak until it got up to operating temp. Then starting again. Puddle under the car in 2-3 minutes. Replaced the oil pan gasket with no change.

Ideas? Could it have bent the rear of the crank when the converter weight came loose? The bent crank could mess the seal up. Other suggestions?

Thanks!

Checking for a leak at the cam plug or a pipe plug at the rear of the block would be a good idea. Also a leak at the back of the intake can sometimes look similarly to a rear main seal leak.

it is common for the intake to leak when you put Cleveland heads on a windsor block if you don't put a very thick silicone bead down. it is very possible that if it was too thin that it pulled loose at operating temp. the last time we used the c302b heads we made an aluminum spacer to fill some of the gap in the end seals and then put silicone on both sides of that because the yates intake that we used was not really for the application but we made it work. good luck finding the leak wherever it may be.

i had a sbf leak oil at the flywheel bolts,in the crank.i dont know if that could be but wouldnt hurt to look.

Thanks

The back of the intake is dry. It fits pretty well. It's an old Motorsports/Roush intake that was made for these heads on a 9.5 block.

The trans will come out tomorrow to get a look at the block and cam plugs.

We will also take a look at the trans pump stator shaft. I have seen them break loose. It would let the converter wobble and cause problems.

David Cole wrote:Thanks

The back of the intake is dry. It fits pretty well. It's an old Motorsports/Roush intake that was made for these heads on a 9.5 block.

The trans will come out tomorrow to get a look at the block and cam plugs.

We will also take a look at the trans pump stator shaft. I have seen them break loose. It would let the converter wobble and cause problems.

I'm confused. Is it motor oil or transmission fluid? From your first post I thought it was motor oil but that has nothing to do with the stator.

It started leaking both engine oil and trans fluid at the same time. Changed both the rear main seal and the trans pump seal. Still leaking oil, but hasn't leaked trans fluid as of yet with the new seal.

These are extremly difficult & time consuming to properly fix right the first time. When i worked in auto dealerships, we used UV Dye, comes in a 1 or 2 oz. bottle, pour it into oil, fire it up & wait for leak, pull trans & with a UV light follow the bright flouroesent trail to the leak. Works everytime, save you so much time, especially in the area youre working in where you cant see it till you dissassemble everything, then cant run engine until reassembled. Think they sell this at the zone & advance, & all you need is a black light bulb in your drop light, dont buy their high dollar light. Good luck, the easy way is the best way, Phil

David,
I have used a couple of methods to test leaks.
While the trans is out, find a way to pressurize the engine oil system (galleys) without firing the engine. Either rig up a pressurized tank or a small external pump setup. If you know somone that rebuilds lots of big diesel engines, they probably have a "pre-oil tank" that you can borrow. If the leak is on the pressure side, this will find it. I guess you can also use a normal pre-oil drill on the oil pump for that matter...

To find a leak on the non-pressurized (valley or crankcase) areas. Use the vacuum method. If it is a race engine with a belt driven vacuum pump, rig up a way to spin the pump with a small motor or drill. The other easier way is to attach a section of vacuum hose to a car (outside of the shop door) to a manifold vacuum port. Attach the other end to your race engine and cap off any valve cover vents. Carefully apply vacuum to the crankcase on the race engine and if you have a leak it will whistle...loud enough to hear and find. If the race engine has an oil dipstick, just shove the hose on the dipstick tube.
This all may sound strange....but it works.
As you may notice, I like strange things. :-) ...'58 Fords....ect.
I hope this helps,
Keith

Found it, we hope. I think the trans fluid leak/first rear main seal was caused by the converter issue. Pulled the trans and then removed the new rear main seal. It was missing the spring inside it (one pc seal). Just never noticed it on the install. Somebody at the Fel-Pro seal factory was having a bad day. It goes back together in the morning. Hopefully dry this time.