My son picked up an 86 Iroc with 305 6 weeks ago. He has been driving it daily with no problems.

Last night, when he pulled into the driveway it started leaking oil enough from the driver side of the engine, enough to leave a trail as he pulled into the garage.

The oil is puddling under the filter, but we put it on the lift and it is not coming from the filter.

It appears to be spraying from the back of the motor towards the driver side of the car. There is oil puddled under the TPI runners and on the brake booster. Most of the oil is sprayed down and to the driver side.

I can find an oil tee beside the distributor. It has the wrong oil pressure sender (non gauge) out the top of the fitting, and a two prong fitting on the driver side. From what I have researched the two prong sender is a cut off switch for the fuel pump. It appears that is the source of the spray but it is so hard to see behind the motor. Is there anything else back there that would have a pressurized leak potential? I have held my hand on the fitting and it gets oily but I can't feel a dedicated stream of oil.

If it is the oil pressure fuel pump switch, is it still available? Having a hard time finding what I would believe to be the right part? Several look right but don't give a real good description of the part. The one I would think it would be is a standard ignition part number ps135.

Be glad to hear other points of view as I don't want to throw parts at it.

 

Thats probably the leak. Can you get a mechanics mirror to look back there?

 

The sending unit is probable leaking but with a flashlight and a mirror you might be able to see for sure.

 

The gasket between the intake and oil galley could be bad too. That fuel pump cutoff switch us usually mounted right above the oil filter on the side of the block.

 

Earlier cars had the T fitting up behind the dist. They changed to using the oil filter passage blockoff plug hole later on.

Not likely to be the intake gasket; there's no oil pressure there, so that won't "spray". Although it's entirely possible that it's bad too, I'm not saying it isn't, but if so it'll just be a relatively slower seep rather than "spray".

OP, be real careful with the brass fittings back there, Don't put too much force on them in any way without supporting them. Yeah I know, they're so eeeeeeezzzy to get to. It's a major witch with a capital B to get the broke-off piece of that out of the block, if it snaps off (as all too often happens).

 

It was the oil pressure sender for the fuel pump cut off that was leaking. My son did all of the work and didn't break anything.

I hit the old sender with a small bit of air pressure and it shot oil out of one of the electrical prongs.

Thankfully O'Reilly had one in stock. With the trip to town, I think it took him about 90 minutes to get it swapped out. He did not act like it was any bit of fun!!!!

 

Always nice to have a happy ending.