It didn't really leak if I just drove around town, but if I let it wind up to 2500 or so for a small stretch, oil would drip like crazy out of the lower flywheel cover hole as soon as I turned it off. The first thing that popped into my head was the rear main seal? Today I finally had a chance to get under the car and pull the lower cover. I hadn't installed the flat plate cover that goes above the lower cover, because I couldn't find the two screws at the time. Anyway, when I pulled the lower cover off, I expected to see oil covering everything inside. To my surprise, the flywheel (front and back), ring gear teeth, pressure plate (outer part and forks) and throwout bearing were completely dry. There was a small drop on the bearing sleeve of the trans and on the adapter plate bolts and but that was about it. Also, there oil between the cover pan and the bellhousing, where the bolt together. I also noticed that the starter had oil along the bottom of it, a tiny bit on the passenger side exhaust pipe where it crosses under the oil pan and on the bottom of the oil pan itself. Could it be coming from the draft tube or from the valve cover and be going into the opening where the plate was missing? If that was the case, I'd think it would be all over the flywheel. At the same time, would the flywheel be spinning fast enough to get all the oil off of it? Could it be the rear cam plug? Wouldn't that cause the same oil on the flywheel? I'm stumped now. I put the plate on today so I'll have to see how it goes.
Usually a leak that ends up dripping out of the flywheel cover, will leave a drop on the lower rear edge of the rear main bearing cap. Won't see anything on the flywheel. But several things will cause such a leak...the rear main is the most likely culprit, since it does it at prolonged higher rpm running. Clean everything real well, on the outside of the engine. then run it long enough to get it to drip, and see if you can see any oil coming down from the top.
oh yeah....one other thing....mostly of them leak out the back, to some extent, so if it's not leaving a big puddle, don't worry too much about it. You will have to get into the definition of big or small puddles, usually it's something like less than 4" diameter, or maybe 6" diameter, is a small puddle.
6" is small? I feel like it's less than that but I'll have to take a pic of it and post it. Just don't remember my '54 dripping and the original motor/pg in this car leaked like crazy so it'd be impossible to tell where it was coming from.
I don't remember exactly how big the puddle under the Edsel was, I think it was in the 4-6" range after sitting overnight....and it would go over 3000 miles on a quart of oil. The corvair I'm working on now leaves about a 3-4" puddle and I pulled the motor to put rings in it, but I didn't even consider trying to replace the seal where that little leak is. It's totally acceptable for that car (to me). We forget that almost all cars used to leak oil from several places, it was normal. But that was 50+ years ago.
I'm not so concerned about the oil leaking, although I'd it rather not of course. I just don't want to screw my clutch up. When I saw that it was pretty dry inside today, it kind of eased my mind a little bit. I also came to the realization that fixing the rear main seal in the car, with the flywheel bolted to the crank, would probably take as long as pulling the motor and taking the clutch and flywheel and bellhousing off to do the job.
I just don't remember my '54 leaking at all. Of course, I didn't have the flywheel cover on it. I guess it could have been leaking the entire time I was driving, in which case there would be no puddle collected to drain out at one time
Some old cars don't leak, my Chevy II is pretty tight right now. Subject to change without notice. But small leaks (less than 6" puddle) are often more trouble to fix, than it's worth. Unless there is some situation that requires you to fix it. Yeah, it's not easy for that rear main seal oil to get onto the clutch. You know there is no front seal in the old 3 speed transmissions, right? it just wasn't a big deal back then to have oil seep out, or cause an occasional drip. By design.
I did not know that. I was wondering how the oil would get to the clutch from in front of the flywheel but I've read where it happened to a few people and of course it made me nervous. I'm about to go for a drive and I'll leave it in 4th gear just to let the RPMs run up and see where it's leaking. I wiped the side cover, the oil pan bottom (especially around the draft tube), the starter and the flywheel cover. Also the flat plate for the flywheel cover was completely dry since it wasn't installed yet so we shall see
It's a 4 main Chevy 6. It's always going to be wet. You can drop the pan & rear main cap to change the rope seal with the chinese finger thing, & check the bearings while you're in there. If it's a newer version, a 2 piece neoprene is usually available.
It stopped dripping after about 20 seconds. The drips were about 3 seconds apart. I'd say it's pretty close to 4".
it will get bigger as it sits for a while. You'll have to decide if you can live with it...you might be able to...????
I checked the oil level today to make sure it's not too low. I checked it cold, as soon as I woke up and it read just above the full line. I drained all the old oil out and added 5 quarts since I don't have a filter on it. I know the oil expands as it gets hot, which would make the pan even more full. I'm wondering if that couldn't be causing the oil to be pushed past the seal? Monday I'm pulling the pan to see how she's looking inside. I'll refill it with a jug of Rotella, which equals 4 quarts, and see how it goes from there
the oil in the pan is not under pressure. And the amount it expands when it gets hot is negligible. The time you allow for oil to drain back to the pan, does have a little effect on the level.
still won't build up pressure, and there is a constant mist of oil in the crankcase when the engine is running, even if the oil is not over full.
I'm in denial about the tear seal so I'm shooting for anything lol. I may tho my old motor back in and just save this one for a rebuild. Anyone have an early 216/235 alt. bracket they want to sell me? I cut Andrey welded the one I have for the new motor
While i subscribe to the adage that there is no chemical fix to a mechanical problem i will share my experience with a rear seal leak on the bolt in my 57. As stated above the rear seal was leaking pretty well, i was reading a post on the stove bolt forum about oil and linked to Bobs the oil guy's page, long story short i tried a product made by ATP, its name is ATP205 and to my surprise it slowed the leak to a seep. just my 2 cents man, have fun and drive the wheels off of it!
Did it affect any other part of the motor? I always think that if it stops that oil flow, it may stop all oil flow
The guy I got it from had the '58 valve cover with no breather, but the 216 style oil cap, so who knows how long it was run like that
I looked into it but it says it's only for rubber seals. I don't know if mine has the rope or rubber seal. Is there a way to tell without taking the rear cap off?
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