Oil leak

[jonsnw74]

I just built a 1776cc and it is leaking oil between the cylinder and the case. Is there anyway to seal it without pulling the engine

[Q-Dog]

Is it leaking on the left side?
_________________
Brian

'69 Dune Buggy
'69 Beetle Convertible
'70 Beetle

[jonsnw74]

Yes, it is cylinder 4

[Q-Dog]

How much is it leaking? Is it coming from between the 3&4 cylinders?
_________________
Brian

'69 Dune Buggy
'69 Beetle Convertible
'70 Beetle

[subhuman]

[jonsnw74]

Almost certain it is just cylinder 4. I didn't see it leaking anywhere else

[Q-Dog]

[jonsnw74]

It's in the middle. It's not a steady stream probably 2-3 drips a second or so

[Q-Dog]

Anything that steady on the left side of the engine suggests oil cooler leak to me. You can remove and reinstall the oil cooler without removing the engine, but it is much faster to drop the engine.
_________________
Brian

'69 Dune Buggy
'69 Beetle Convertible
'70 Beetle

[enjoyther1de]

X2 I just replaced my oil cooler seals due to oil leaking on the 3 and 4.
_________________
HBB took me to BBV.

[jonsnw74]

Not what I wanted to hear since I just put the engine in. I hope it is the oil cooler, that is a whole lot easier to fix

[jonsnw74]

It wasn't the oil cooler. It looks like the bottom of cylinder 4

[awreed]

If it's the cylinder you'll be pulling the motor and removing and resealing that side again. Clean the oil off the cylinder base and case with carb/choke cleaner or brake cleaner and make sure the surfaces are good and dry and oil free.

[jonsnw74]

I've been driving it for a couple weeks now and I've noticed that it doesn't leak right after an oil change but once the oil starts to get dirty it starts leaking. Would a heavier weight of oil stop this? I've been running 10w-30. I'm in michigan and this is my dd for the summer

[awreed]

Oh man. You don't wanna start the oil discussion topic on here. That is one prickly topic that will get the old farts on here fighting in no time.
If you have the time and patience to pour through it, this is the thread:

http://www.thesamba.com/vw/forum/viewtopic.php?t=220755

I would advise against using a heavier weight oil or a Rear Main Seal stop leak additive as these are just band-aids covering up an underlying and serious problem.

That said, I don't understand how dirty oil would cause your leak while new oil wouldn't. Usually oil leaks get progressively worse/heavier with temperature, not contamination. 2 to 3 drips a second, as you described, is pretty bad. If that starts up again you might want to pull that motor and reseat the 3/4 cylinders. I know it's a pain and you just got the thing in and running, but you've gotta take care of that oil leak.
What did you use to assemble the cylinders? From what I understand there are no paper gaskets larger than the stock 85.5mm, so most people either use nothing or RTV. I've always used the high temp. silicone, though using it to mate the cylinders to the case can lead to chunks breaking off and squeezing into your crankcase and eventually your sump and then the oil galleys. It's a risk, but I've never had leaks from the cylinders with RTV.

[jonsnw74]

I did pull the engine back out and sealed everything up again. When I put it back in there were no leaks until the oil seamed to get dirty

[awreed]

Always leaking from the same location between 3 and 4 cylinders? And definitely not the oil cooler? Did you put any oil dye in the case to pinpoint the leak? Was this a reused case or a brand new one?

[jonsnw74]

It is an old case than I don't know the history of. When I pulled it back out oil was leaking from the bottom of 4 so I sealed everything back up and put it back it. The leak was gone almost completely until the oil gets worn. I guess it is possible it has to do with heat but I'm not sure

[awreed]

Jon, this is sounding more and more like what I went through, and you might not like where it leads.

The first motor I built was a 1776cc for my Super Beetle. I used the original dual relief case and crank and had everything machined.

After about 50,000 miles it started leaking pretty good from the left side. It really looked like a leak from one or both of the 3/4 cylinders, so I pulled the motor and resealed the cylinders. Put the motor back in and nothing had changed: leak was still there. Did a little more investigation and learned that the cases can and will crack. Hundreds of thousands of miles on these soft magnesium alloy cases can produce hairline cracks that you can't see with your eye and that will weep when the oil gets nice and hot. That must have been the case with my motor.
I pulled the engine again and resealed the cylinders a second time (rechecked the oil cooler seals too). While the motor was on the ground the second time I pulled the tin off and ran it out of the car to try and pinpoint the leak. Because there was no cooling tin, though, I couldn't run it long enough to produce the leak. I really went over the case up close (especially on the left side) but couldn't see the crack that had to be there. The case was oily between the 3/4 cylinders, but absolutely dry and clean everywhere else.
My conclusion was a crack between the cylinders. The fix: strip down the motor and rebuilt with a new case.

Now I'm not saying that this is necessarily the case with your motor. But the symptoms you're describing don't really make sense with regards to dirty versus clean oil. If resealing the cylinders didn't work, then I would suspect a leak from somewhere else.

Buy a bottle of the UV dye. You will clean your motor real good, put the dye in the case, drive around to produce the leak, then use a black light to see exactly where the oil is coming out. If it really is the cylinders then you're lucky- sort of.

[jonsnw74]

That makes sense in my case since I have no clue about the condition of the old engine. I think I am at the point where it is no longer a dd and I need to park it to get it where I want