Oil Leak
 

Hey guys
I just got a 1928 Model A from my dad. He took great care of it and had a new engine put in, though he doesn't remember when, I'm very certain it was within the last 10 years and he hasn't driven it much since then and it's been in his garage for the last two years, untouched. I got it running but I have an oil leak coming out of the cotter pin hole in the bell housing. It only seems to happen when I go up my driveway, which is fairly steep. Here's where I'm confused though, why didn't it leak when it was being unloaded from the flatbed tow truck, which would've been as steep as or even more than my driveway? I was thinking I had a rear main issue, but wouldn't it have been leaking off the tow truck if that was the case? I know that someone stuffed something in the oil fill cap, should I remove that? Thanks for your help!

Re: Oil Leak
 

When the engine runs, the pressure in the rear main bearing rises into the thousands of psi, so oil flow out of the bearing is substantially more. Unfortunately, the design of the rear main bearing oil drainage is poor, and some oil overflows into the bell housing.

Re: Oil Leak
 

So, then would removing whatever was put in the oil cap help with that pressure?

Re: Oil Leak
 

Definitely. There's always some pressure buildup in the crankcase; it needs to breathe.

Re: Oil Leak
 

It takes a bit of time for the leaking oil to make its way after spilling over the rear cap. The oil first deposits to the front side of the flywheel and then when beyond capacity to hold, drips to the flywheel housing. From there it makes its way to the drain hole where the cotter resides. At that point you will see drips. The off loading from the trailer may not have been enough time.

Something stuffed in the oil filler tube: Yes remove it before driving the car much. Some of us call it the "breather" tube.
Good Day!

Re: Oil Leak
 

Wait a minute. A Model A with an oil leak at the rear of the engine? :eek:


Actually, if they are not leaking...you're probably out of oil. :D

Re: Oil Leak
 

Check your oil cap and remove that stuffing. I had a new cap and the stop tabs wern't bent so when the cap went on it was closed off and built up pressure forcing oil out the rear main.

Re: Oil Leak
 

How much is it leaking. Is it a stream when you go up the driveway or does it leave a puddle after shutting it off. If it is a puddle how big is it?

Did you add oil and bring the level up to the full mark? Some engines don't like to be at the full level. Running halfway between the add and full is fine and a bit lower than that is okay.