Chevy oil leak??

[rshaw125]

You will have to eliminate causes along the way. Is it leaking around a valve cover gasket? Oil pressure sending unit? Clean the areas up and watch for leaks.
If its a seal a high mileage oil might work for you.it'll take a few thou. to take effect.
If the PCV valve is bad it can build up pressure in the crank case and cause a leak to get worse.

 

[pgun67]

It is not a valve cover leak as it is dry from the top of the engine. The lower engine is also not a problem. It seems to be coming from somewhere between the trans and engine above the flywheel. Just hard to see the source or anything else from underneath. I will try to check the sending unit as stated above. I replace the PCV at least twice a year. thanks for the feedback.

 

[pgun67]

I have a slight oil leak on my Chevy 5.3 that will not go away. It seems to leak oil and drip down to the oil drain plug and blowing all over the undercarriage. I can't tell where it's coming from. I have checked in the little removable shield to the flywheel gear area and it is dry. I have tightened every bolt under the engine I can see and still it drips. It seems to go til about a half quart low and then seems to stop some. I have done 1 Autorx treatment and it leaked worse. Should I do a second treatment now 3 months later? Any advice or ideas appreciated.

[ April 17, 2006, 01:01 PM: Message edited by: pgun67 ]

 

[m2200b]

sounds like the rear seal and the 2nd ARX might help. I had a qt a 1000 mi before and after the first ARX and it slowed to maybe a gt in 2000 only into the 2nd rinse of ARX.

 

[babyjay8495]

The 5.3 does not have a distributor. They have 8 individual coils.

 

[acewiza]

Nope, he said "above" the flywheel. My bet will be the distributor. This is an easy fix, too. Not sure about the Chebbys, but if they are anything like the Mopars I've done, there will be a hard rubber O-ring "type" seal around the dist mount that is either hardened and/or damaged. I say "type" because it is not exactly an O-ring per-se, but very similar.

Get a similar (preferably thicker) O-ring, turn it inside out and use a grinder to flatten what "was" the inside. Turn it back around, install on the dist, re-insert and set the timing.

You may get lucky and do it with an appropriately sized round O-ring, but flatening one side makes it stay put when you install the dist and allows you to use a big enough ring to ensure a tight, leak-proof seal. Round ones will tend to slip out of place if they are big enough to seal. That's why I originally said it was a O-ring "type" seal.

 

[ddean]

Does this engine have a crankshaft driven rotary oil pump in the timing chain cover or an in the pan spur gear type? A dummy shaft is needed to drive an oil pump in the pan on a distributorless ignition system. I know many of the GM 3100 were like this and had problems with leaky O ring gaskets on the dummy shaft.

Also a rear camshaft plug might be leaking. Does these engines have balance shafts installed like the camshaft? If so then a rear balance shaft plug might be leaking as well.

 

[Matt_S]

It could be the camshaft seal, but V8's don't use balance shafts. The oil pump on the modern 4.8, 5.3 and 6.0 liter engines is driven off the crankshaft and mounted to the front of the engine, underneath the timing chain cover, so there would be no dummy shaft to cause a problem.