Oil pressure problem in '71 455

[elwood565]

I have a '71 98, and the oil pressure light in the dash came on. I think I've traced the problem to a small leak coming from the oil pressure warning light switch, as I noticed a small puddle of oil collecting on the top of the water pump. And when I would run the engine while watching, it would slowly run out from the switch.

I am a little disturbed by this sudden problem, occurring just after getting an oil change. Normally I would have done it myself, but was pressed for time, so I went to the GM goodwrench quicklube at my local dealer and they took care of it. They put in 10-w40, and I am wondering if this may or may not have contributed to the problem, it being a slightly heavier weight. But the owners manual says that 10-w40 should be no problem in summer weather.

Any Ideas?

Thanks guys!

[Yellowstatue]

A small leak at the oil sender would not cause the light to come on, just makes things messy in that area...if the light is comming on at idle maybe the idle is too slow...the sender triggers the light at 3-5 lbs pressure so maybe the sender is starting to fail, it is leaking anyway so change it...maybe put mechanical guage on there to check pressure before purchase of new device

[Olds64]

I would think a leak at the oil pressure sender on the engine would give you an erroneous reading. If there is a leak then the pressure is escaping and wouldn't fully activate the electrical circuit to prevent the trouble light from illuminating.

[jensenracing77]

even if you don't want to leave it on permanently, you should put a mechanical gauge on it to see just what you have. if it is good then just put a new sending unit on it.

[J-(Chicago)]

I hope it's just a bad sending unit.
I have an extra mechanical gauge and the proper socket for the sending unit here if you need to borrow them.

usually you can get it out with some channel locks pretty easily though.

3 psi of oil pressure usually means the motor is junk. I wouldn't run it anymore until you get a real gauge on there and prime the oil pump to check.

[elwood565]

I'm hoping its nothing serious too. I would be really be surprised if it was something serious, as the car has been running fantastically. Although these serious problems tend to come from out of nowhere.

J-, It would be great if I could borrow your supplies. Better yet, I am no seasoned wrench turner, and I would greatly appreciate some help with this problem, if you have some time. If you can't thats fine, I'm not trying to guilt you into this or anything, haha. I have a buddy out in the burbs who normally helps me with this stuff, but he's been swamped with work and unable to come downtown to help me out. I have not been running the car since the light started coming on and staying on.

[Olds64]

Good luck. Keep us posted.

[elwood565]

It was simply the switch. I had some extra cash to finally be able to do something about it, so I called up autozone, and they actually had the part IN STOCK. I was amazed by my luck. I had to buy the proper socket, but it was still significantly cheaper then I had expected. I was actually mad at myself for not getting off my lazy arse and calling autozone sooner, once they told me they had it in stock. But I got back home, swapped in the new switch and all was well again, no oil pressure light coming on, no nothing. I put a little over 200 miles on the ol' boy the very next day and he performed like a champ.

Its very nice to have the big guy back on the road, and I dont pretend to be any knowledgeable wrench turner, so even this simple fix was a nice victory for me, having properly diagnosed the problem, and solving it.

Thanks guys!

-Bob

[citcapp]

Pat on the back, good job. Save some money and put a set of under the dash gauges on your car, better safe then sorry.

[Olds64]

I think we all know who the man is!

[elwood565]

Thanks Olds64!

And thank you citcapp. I believe I will put some gauges on under the dash. What brand would you recommend as the best?

Bob

[svnt442]

Autometer.

[citcapp]

Originally Posted by svnt442

Autometer.

X2 good gauges and not priced out of site

[elwood565]

Sounds good to me. Thanks guys!

[Olds64]

I agree with the Autometer. I have thought about putting some in my 71 98. Post pics if you install them.

[elwood565]

Will do. I've thought about installing gauges before, and I'd kinda like to find a trick way of doing it, so they could be hidden when the car was parked. I'm thinking of using the ashtray....

Bob