wadey

Have had a small but annoying oil leak for the last 2 years. Had my machanic booked to install
the rear main but after removing the oil pan and inspecting the area directly under the seal
decided not to change it.We checked the area with a trouble light and everything looked so
dry we decided not to go ahead.The leaking oil was running down the face of the flywheel
inspection plate,collecting on the bottom of the plate then dripping on my garage floor.I still
have the leak and no answers,should we have changed the seal anyways?Any other place the oil
could be coming from?New rebuild,2500 miles.
help please
thanx wade

Aaron-74

The back of the intake, or your oil pressure sender. But, it's probably the seal.

Twin_Turbo

Year of car???

If you have an oil pressure sender next to the distribuer, they tend to leak at the crimped flange. Or take a look at the rear manifold seal, they are common leakers, replace with thick line of silicon, do not use the rubber gaskets

Marck


[Modified by Twinnie, 3:53 AM 6/26/2002]

yellow 72

I also say take a good look at the rear of the intake, a very common place to leak :cheers:

Fevre

I see that a lot and wonder why then do they keep producing these seals? Any scientific, not anecdotal, evidence to say they are more prone to leaking?

Just curious

BTW I keep using them with a line of sealer above and below them with no problems.

Twin_Turbo

The old ones had small holes in the block and the seals had little bumps. Those held up pretty good.

I think they keep making them to stuff in the gasket kits & charge money.

Marck

Frankenvette

I replaced my rear main seal and still have the exact oil leak you describe. I had replaced my intake several years ago, but I think the leak is coming from the rear of the intake. I have already added teflon tape to the oil pressure sender to seal it. You can purchase an ultraviolet additive to your oil. Then you use a blacklight to find the leak. I'm really thinking of doing this before I start taking apart anything else. I hate making extra work for myself but really want this oil leak gone!

Regards,

Jim

Paul L

Jim is bang on. Use this dye and observe the leaks with a UV/black light to see exactly where they are coming from. Cost is about $4.00.

*Edit*-Oops, here is the pic.




[Modified by paul79, 6:31 PM 6/26/2002]

Richard Cooper

Paul79, Can you tell me where you got the tracer dye from. It's a great idea. I have a ton of oil leaks and I would like to try and find some of them. Thanks.

fontking1a

My rear main seal has been leaking since 1970...when I got the car. It's a 50 cent piece size puddle after two weeks and really no big deal. I've thought about fixing it, but there is really no guarantee the new one won't leak more. I've left well enough alone for 30 years and the extra oil is insignificant. Sometimes cars just leak...it's inevitable....especially with the older technology.

bob

Possible that the plugs for the lifter galleries have a small weep. If you had the motor rebuilt around the time the leak started that might be a thought but if the plugs have been in for 30 years that probably isn't the case. If there was oil coming from the intake or oil sender I would think for enough to sneak down into the bellhousing there would be quite a bit dripping externally also. One last long shot, are you sure it is engiine oil because if you have a muncie, a plugged drain back hole can make a leak similar to what you have and with the flywheel and clutch spinning sometimes where it is coming from gets hard to tell. I still wouldn't count out your rear main seal.
bob

Paul L

Richard,
The dye is used by GM dealers to diagnose engine oil leaks. It sells over the counter for about $5.00.

The engine must be cleaned before dye is put into the crankcase. When to hit the engine with UV/black light is a little tricky and depends on the severity of the leak(s). For a moderate leak I suggest driving about 100 miles. For more severe leaks about 25-50 miles. The tricky part relates to the fact that leaks can merge into an oily mess and disguise their origin. Then you only see a nice pink oil pan and bell housing. Not very helpful. The nice side of the product is that the dye does not degrade. So if what I described happens, you can re-clean the mess and start again.

GTR1999

Paul, this may be a dumb question but where do you get a blacklight?
Gary

rollavette71

Gary,

I purchased one online at http://0-0-0Checkmate.com/ (search on "black light"). The one
I bought was $7.95 + S&H and uses four AA batteries. There may be better deals, but this
light has worked well for me so far. :cheers:

Hank