OK, took the Blazer in for inspection and the mechanic tells me it's leaking a lot of oil. I have seen oil on the garage floor while I was fixing the other stuff so it's not all that surprising, except that he says it's leaking a lot. He's going to spray it with a degreaser, I'm going to pick up some oil dye and get the underside cleaned at the car wash. What would be the possible culprits for a large oil leak? And no, at this point I do not know how large it is.

 

Front or rear crankshaft seal, valve covers, oil pan, intake manifold, oil pressure sensor, oil cooler lines, filter adapter...

The list of possibilities is long.

 

Of Tom A's list, I'd only add that the oil cooler lines are generally considered the most likely culprit. Replacing these is almost a right-of-passage for Blazer owners! LOL

I did have the o-ring for the adapter to where the remote oil cooler lines go to the block (filter adapter) fail on me in my 92. It lost LOTS of oil but I was able to drive it to a shop to have it fixed. (I didn't have a garage then.)

There can also be oil leaks from a loose nuts that secure the rear of the oil pan but that is more on the annoying level instead of the concerning level of oil loss.

 

Thanks, one of my buddies here also suggested oil cooler lines as most likely. I take it this AM to a car wash that does the undercarriage and I will look at those first. Any tips on do's and don'ts on that job? How tough is it and how long should it take?

Thanks!

 

OK, it looks like it could be coming from the adapter on the bottom of the engine that the hose assembly mounts to and it looks like it's held in place with two bolts straight up into the block. Does this sound logical?

 

Oil cooler lines... sounds about right.

 

Alright...it's coming down the passenger's side above the starter but I can't see where it's coming from and it looks like I might have to pull the fender liner to see better. What could be culprits from that area?

 

Hmmm not sure but maybe the valve covers? Trying to think of other items, in the middle of work so back and forth lol

 

I have gotten the passenger's side VC off and the gasket doesn't look bad but the dye in the oil lights up all the way up the rear of the block as far as I can see from below and the starter obviously took a pretty good bath.

 

Does the oil that is leaking start at the valve cover?

On the passenger side I can't think of anything other the valve cover that could cause a leak.

But, at the back of the block there where the distributor goes in and the oil-pressure sensor that could be leaking. And there could be a leak at the rear end of the intake I guess.

Based on what you've reported, my bet would be the oil pressure sensor. Of course being back against the firewall, inspecting it sucks. LOL