whacky oil pressure

[klb76]

The other day, before my flat tire... haha... I notice my oil pressure was going all over, everywhere from 20 to 80 on the gauge? I assumed it was the sending unit or the oil pump, but when talking to my mechanic about getting my oil leak fixed he seems to think it is something with the leak.... Told me his 77 had the same problem.. Has anyone heard of anything like this before?

 

[rpounds]

My '75's gauge goes nuts at highway speeds. It has always worried me that there may be too much oil being retained in the top of the engine and starving the oil pump. I have no evidence to substantiate this worry. But, all of my connections are tight, the sender is good, the ground is good . . . and it only happens after the car has been running at highway speeds for a couple of miles. Is this the way yours acts? BTW, I should mention that I run 10-40 multigrade dinosaur oil . . .

 

[cntrhub]

A simple oil pressure tester at the oil filter housing (where most fittings are placed to inspect oil pressure) will tell you exactly what is really happening. It will be the very first pressure reading (after the filter) out of the oil pump assembly. If this reading is within specs, then you can begin to chase the sending unit or dash gauge.
And rpounds, the crank is the first to be lubed. Therefore, the oil from the crank will return to the bottom of the pan way before the oil from the top end gravitates down. The bottom end uses more oil to lube the engine than the top end. That engine would have locked up, and be cooking on the side of the road years ago, if all the oil remained on the top end. Your worries are over for now.

 

[Bob Chadwick]

My 77 ranges frim 20 - 40 psi. Below 2500 rpm it will on occasion bounce around between the two despite a constant foot on the accelerator.

I just put in a new oil pressure sending unit but have no had an opportunity to see if that was the problem.

Bob

 

[cruzer99]

Just to make you feel better you might think about a mech. after market oil pressure guage temporarily just to see if it does the same thing.

 

[Bob Chadwick]

Took my gauge in to a shop here to try and get this fixed. At first they thought it was the resistor but after bench testing it it appears to be the needle. It appears to use friction to put it in place and it slips.

I would prefer having the gauge rebuilt rather than replacing it with a new one. I've read that the needle and black fades over time and that a new one might not match the exisiting gauges.

Can anyone recommned a place to send this for a rebuild?

Bob

 

[jmp]

The other day, before my flat tire... haha... I notice my oil pressure was going all over, everywhere from 20 to 80 on the gauge?

What do you mean by 'going all over the place'? My pressure changes depending on the load on the engine -- but this is normal. The only time I got worried about it was when the range when from 20-70 to 5-25. A quick look at the dipstick showed that I was down about a litre (quart). Added the oil, and everything was OK again.

PS. There's lots of posts on this topic -- do a search for more info!

 

[cmegga]

I have a oil gauge the work fine all day, until night comes and I have to turn my lights on. I het some type of electrical interference and my guages dances all of the place. I also drop 20 degrees on my temp guages with my light on ..

wacky car . i never know what the hell is doing.
Atleast it bug me still spring anyway.

 

[Bob Chadwick]

Re: Re: whacky oil pressure

What do you mean by 'going all over the place'?

It goes up and down rapidly, like a vibration, very quickly, perhaps several times in a second. If you take a pencil and put it between your thumb and forefinger and make it rock back and forth rapidly you will get the idea.

The bench test found it to be working with the exception that the needle appeared to be slipping on the spindle causing the very rapid fluctuation.

Bob

 

[c4ever]

Bob,
Ecklers has a guage rebuild service and the prices aren't too bad.

Merry X-Mas

Carlo:SANTA

 

[Bob Chadwick]

Thanks Carlo.

I'll check into them and Corvette Clocks by Roger, who got a good recomendation as well.

Bob

 

[rpounds]

Bob,

I checked out your website while checking up on this post. Great job! The vette looks great. I love this type of site showing ongoing work and upgrades. Thank for sharing it!! Keep up the good work!

Ron

 

[Bob Chadwick]

Thanks Ron. It gives some satisfaction to go back and see the progress made over the last year (and to be able to explain where the money went to the wife).

Bob

 

[Bob Chadwick]

I'll check into them and Corvette Clocks by Roger, who got a good recomendation as well.Bob

Ecklers informed me that they ship them to Corvette Clocks by Roger. Eckelrs wants $57.99. CCR does them for $40 plus parts. Ship to CCR's address with your credit card info and they will repair it and ship it back to you. www.corvetteclocks.com

Bob