Are you sure it's leaking or is it just Sweating from All the Horse Power!!!! 

And don’t forget those two oil pan bolts that go into the rear main seal retainer.  Those were originally studs and if replaced with bolts, make sure the threads are coated with some kind of sealer.  If the studs had been removed and resinstalled, some kind of thread sealer will be required again.  Leakage past those threads looks just like a rear main seal leak.

Lorena, Texas (South of Waco)

I can't figure this mess out. I am now going to pull the engine and transmission and try to figure it out over the winter. My T-5 leaks too so I can try to get it sealed at the same time. Thanks for all the help. If I can't figure it out I have two options : rebuild as a 292 or go back to a 272 I have. Again, thanks.

Jan  Urbanczyk  Major USMC Ret.

                                                                 Bowie Maryland

Glad I read this thread. I am rebuilding a 312 and just put in the rear main neoprene seal from Best Gasket. It looks like it fits well, but based on feedback should I go with the Fordcraft one? Now is the time for a quick change due to it being apart.

Idaho: Don't know from personal experience.. however, I've read that some 312 castings vary somewhat in the seal area. In those cases the Best Neoprene seal may not fit well & the new Graph-Tite rope seal may be the better bet. Or you could go with Ted's method. You need to examine it carefully & decide. Others here may confirm this or not?..

Paul

Just wished to add an update.  Pulled the engine today, when I drained the oil, I found a lot of water in it.  I guess I blew a head gasket, and I think that seals probably don't do well with a lot of oil pressure and water.  I am glad that this car is a "hobby" and not an investment.  Maybe I will have this thing running by spring.

Jan  Urbanczyk  Major USMC Ret.

                                                                 Bowie Maryland

Jan,

Hang in there, buddy. Major, don't forget the last part of the Marine Corps code... Commitment! The young man that just graduated from boot camp down at Parris Island let me know all about the Honor, Courage, and Commitment of the Corps. I am taking him to lunch tomorrow (he lost a lot of weight down there!)

I am cleaning up the garage just in case you can come by. I know I am a little ways away from you, but if you need to use my engine run stand, I would have no problem with it.

dan

Daniel Jessup

Loveland, Ohio

aka "The Hot Rod Reverend"
check out the 1955 Ford Fairlane build at www.hotrodreverend.com

Not familiar with the rope gasket in a Y-block but changed countless ones in Chev 6's and GMC's. I have found that the "hash" marks need to be there and can be felt with your finger nail to work properly. When the GMC's got hard to find I when to the Fords and have had very little trouble with originals and Best's. I love to find the old asbestos ones as they are the best. I always cram in all I can in the groove both top and bottom. I also leave the block side a little short by pounding it up inside then leave the cap a little "high" on each side to fill the gap. This stops leaks also. I've even used set screws in the cap to keep them from turning.

I know this may sound s little crazy but the use of a PCV valve keeps the engine at low driving/crusing speeds in a vacuum. I'm reluctant to do this on my 56 but I know it works and does not hurt an engine that's fresh. The vacuum definately helps with minor leaks.

Most racing engines today run with as much vacuum as they can and not only use their dry-sumps for this but belt driven vacuum pumps also. I use on on my LSR engine....Just a thought..........  

56 Vic, B'Ville 200 MPH Club Member, So Cal.

A note on the Best Gasket Kevlar rope seal. The seal comes with a small pin that is recommended to be installed in the seal holder, to prevent slippage during installation.

Paul

Another update, I guess that i am getting better, there was only water in number seven cylinder this tme. I hope that further tear down will expose the problem.

Jan  Urbanczyk  Major USMC Ret.

                                                                 Bowie Maryland