355C Oil Leak

[packrat]

Hello again,
   I have been away from the forum for several years but am now going back to work on my 1933 355C. When I loaded it on my rollback (not running) it left a trail of oil from the rear of the engine. Now that it is running, it leaks oil from this area when the engine reaches approximately 2000 rpm. Naturally I assume this is the rear main seal. I have the proper Shop Manual and Master Parts list. After much reading I find that there are two wooden dowels used somewhere in this area. I found the p/n 874048 "Wood, 3 1/8" long". No diameter mentioned. I will pull the pan and see if they are missing or? This engine was supposedly completely rebuilt in the 1980's and never ran. It does run fine with good oil pressure. Can anyone please shed some information on this part and it's purpose? Thank you.
P. Dow

[Johan Boltendal #158]

Most likely, with a restored engine, a non functioning oil return from the rear main.
The seal you mention, seals the cap in the crankcase. Can leak oil of course, but not rpm connected.
Wood most likely replaced by gasket material.
Pan off is a good idea, look for a passage hole, missing in the pan gasket, return blocked within the pan, check the oil return itself to the main bearing.
If at the restoration the main is not within factory specs. the oil will be pumped out at the oil return at the rear,
because it cannot cope with the oil pumped out.That's the worst scenario. Also a broken oil return is possible.
Please let us know what you find. Johan

[packrat]

Thank you Johan, I believe that you are the gentleman that has helped me immensely in the past.I will let you know how I make out.
Paul Dow aka Packrat

[packrat]

Johan,
  I removed the pan. First, the return hole in the gasket is present. Even though it was drained it seemed heavy. I removed that beautiful windage tray and found about 1/2-3/4 inch of strange "sludge". It was quite liquid with the viscosity of honey and was blocking the outlet of the return in the pan.. It was not anything like the sediment I have found in the bottom of old poorly maintained engines. This engine has been run very little since its rebuild in 1977. The only thing that I can figure is that after the rebuild it sat in some poor environments for many years. there was no water present but under the sludge was evidence of rust. I have cleaned it thoroughly, installing a new gasket, and will take a look at the filter before I try again. Thank you again for your input