oil leak from heck! - Lateral-g Forums

carkrazy1987 · #1 09-10-2013, 05:29 AM

Ok so Im working on a friends truck and we are having one heck of a time getting rid of an oil leak. Alil background. 1994 s10 with a 383 sbc vortec. So far what we have done.

Balancer seal is leaking.
Replaced balancer seal. Still leaking
Then replaced plastic timing cover. Still leaking
Removed cover found double roller chain rubbing on cover, replace cover and installed hd timing chain. Still leaking
Replaced balancer. Still leaking.
Installed a sleeve to balancer, still leaking.
All gm parts used.

This is were we are at. Next option is maybe to try an aftermarket metal cover. Any ideas?

MarkM66 · #2 09-10-2013, 07:19 AM

I never even knew there was such a thing as a plastic timing cover for sbc.

When there are multiple oil leaks, I would look at your crankcase ventilation system. Sounds like pressure is trying to escape anywhere it can.

**GregWeld** · #3 09-10-2013, 07:23 AM

That would be my exact response -- bad PCV valve or that system failure somewhere.

**camcojb** · #4 09-10-2013, 07:33 AM

In addition to the above, are you sure the leak isn't from the front of the oil pan where it meets the timing cover? They make a thin and a thick front seal depending on the oil pan used; if you use the thin older style pan gasket/seal it will leak badly with the later oil pans, and most aftermarket pans.

**Sieg** · #5 09-10-2013, 07:44 AM

Excessive pressure - based on all your efforts to date.
PCV and breather condition?

Condition of crank snout?

The front pan to cover seal design is poor at best.

Most builders I know rely on the Right Stuff: http://www.permatex.com/products/our...he-right-stuff

Mating surfaces cannot be too clean.....I have a new Milodon pan and cover, engine assembled in the shop with the Right Stuff and it still weeps a little oil.

Getting that area to seal with the motor in the car is tough not to mention a real PITA.

carkrazy1987 · #6 09-10-2013, 08:53 AM

I was also thinking pcv system. Its not coming from the pan that we made sure. We were actually able to see it make its way outta the crank seal. Imma look into the pcv system next.

Vegas69 · #7 09-12-2013, 08:31 PM

On a small block chevy, you need to silicone the inside of the balancer snout as well. Otherwise, the oil will travel between the crank gear and balancer snout, then out the snout.

**GregWeld** · #8 09-13-2013, 06:30 AM

Quote:

Originally Posted by Vegas69

On a small block chevy, you need to silicone the inside of the balancer snout as well. Otherwise, the oil will travel between the crank gear and balancer snout, then out the snout.

You'd really need to explain that one to me..... :>)

What I've always done is to use a little gasket sealer (never silicone since it will not stand up to oil and gas) on the keyway in the crank/balancer.

Also - what a lot of people FAIL to do, is to put a little oil on the balancer exterior surface that meets the SEAL ---- fail to do that and you ruin the seal surface on the first fire up.

**Bryan O** · #9 09-13-2013, 07:46 AM

Check the crankshaft sprocket key. I had the same problem you describe. Replaced the key and no more leak.

carkrazy1987 · #10 09-13-2013, 09:45 AM

We used gm gray rtv on the balancer key, always have. Its not leaking from there. I know it from the seal and I'm almost 100% sure its due to excessive crank case pressure just finding the easiest way out.

As per request the pix of the pcv hose hook up.

Goes from pcv to port on carb base