Oil leaks.

[moody]

I have a major oil leak. What are the most likely sources other than the rear seal?

I'm just looking for some thoughts on this so I know what to look for when I get back to it.

Truck is an 86C with 366,000km on it with no major work ever done to it. Has had a small front and rear seal leak for the past four years.

[NH2112]

I'd have to say oil cooler lines and block adapters, and the oil filter mounting boss itself. I'm not sure about the 6.2l but a lot of filter mounting bosses have the threaded nipple secured with a setscrew that runs up the middle of the nipple. The oil pressure sender could be loose or have a crack, that would obviously cause a major leak.

[moody]

thanks had not thought of the oil filter boss itself.
I did check the oil lines and I belive they are good.
Would the oil sender leaking would show as a pressure drop on the gage?

[snoman87]

can you determine the general area? Front, back, drivers, passanger.

Now that I have pressure washed my engine it appears that my oil leak is coming from a few spots; water pump to timing cover seal, valve cover and lower alternator bracket bolt threads ... apperently there are a few hole threaded straight into the coolant or oil passages along with my rear main.

The good news is that I no longer suspect the front seal!!!!

[moody]

I am pretty sure it was coming from the back of the engine. I have had a water pump leak also now that I think of it.

I spoke with one of the dealership repair coordinators on Friday and she convinced me to drop it off over the weekend and they could come up diagnosise while I was out of town this week.
Of course I get a call on Monday asking if I could get it off their lot. "There is to much oil on the underside for them to find out where it is coming from. Could I drive it for a few days and come back with it cleaner?"

[snoman87]

I bet if you get in nice and clean and then inspect it everyday after driving it you'll find the leak yourself ... I hate going to dealers :)

[moody]

If I had not had to leave town I might have done that. I guess I should have just watched the pressure gage and driven it untill I had the it figured out. I was a little worried about damaging it.

Oh well just had to re-learn the lesson about doing it yourself.