Spewing engine oil!

[threepiece188]

After parking in the garage from my trip home from work last Fri. I noticed a stream of oil on the driveway with two 12 in. dia. puddles before and after the gate which I had to park to open and park to close. The next morning I noticed the oil was leaving from what I would guess to be an oil pressure switch. This switch is Tee connected in with the oil sending unit on the right side of the block in the rear of the 258 I6 engine. It is made in two halves, one of steel and one of a plastic or pheonolic material. It is about 1 in. in dia.x 1 in. long and has two spade terminals comming out the plastic end. Perhaps someone knows what this is and what it is for. It seems the plastic had failed and was leaking out from the spade connector area. This switch was the original 1983 unit. I feel extreemely lucky I wasn't on a longer trip that day as I would have surely dumped all my oil within a few miles, especially if I was in the E-way.
Dan

[addicted]

That's the sending unit for your oil pressure gauge and that is how they typically go bad, at least in my experience with them.

[joe]

Look closely to where the sending unit srcews into the block on a 258. it's common for the block to crack outward from the hole.

[threepiece188]

Simon, I thought the sender was the larger unit, about 2 in. in dia. and made entirely of pressed steel. I suspect this defective unit is the pressure switch that closes the warning light circuit.

Joe, I had oil and air spitting out from the two spade terminals when I applied shop air to the inlet port of the switch. I have never seen or heard of a 258 block crack in that area. I wonder if that might have anything to do with over torquing the tapered pipe thread to stop a leaking condition. I'll be sure to use a sealant with minimum torque in the future! I will also not be using a pressure switch in the future. It's ironic that a device intended to protect my engine would be responsible for destroying it.
Dan

[crazyspoons]

Did you get any new vehicles lately? It sounds like your jeep is just marking it's territory; actually a pretty common occurrence.

[addicted]

Simon, I thought the sender was the larger unit, about 2 in. in dia. and made entirely of pressed steel. I suspect this defective unit is the pressure switch that closes the warning light circuit.


It's been a while since i've really dealt with a 258. The past few years have been all 242's (4.0) but I remember there being 2 now that you mention it. I think one is for the gauge and one is for the choke, so if it stalls when warming up it doesn't keep warming the choke coil and make it hard to start with a cold engine and warm choke.