wacky oil pressure gauge

your sender is bad, replace it.

7psi idle, 10psi per 1k rpm is the service minimum.

Should there be a significant

there can be... on a new motor with tight clearances, it is completely possible to be up against the oil pumps pressure relieve valve at all times, leaving a constant oil pressure... as the motor wears, the oil pressure will slowly go down below the relief pressure of the valve and you'll see the fluctuation.

if you've got more than 7psi at idle and more than 10psi at 1krpm,

20@2k, 30@3k, etc your motor is just fine.

oh and one more thing... the factory electrical gauge is notoriously inaccurate.. I've got a mechanical OP gauge in my truck and the factory gauge can be reading +/- 5psi (or more) from the mechanical gauge.

hth, Bret

Thanks, Bret- that is very helpful!

Tim

I replaced the sender on my 88 Suburban 5.7L for this very reason. I replaced it with a Sorenson brand I bought at Advance Auto. The new sender moved the gauge in a step-wise fashion. Instead of moving smoothly up and down, it goes up and down in ~7psi increments. After 1 month, the new sender is again bouncing around like the old sender. :-/

-RC

R.Clarke spam snipped-for-privacy@BlocKmindspring.com RTP, NC, USA

It was a defective sensor when you got it!

It's actually a transducer.

Was it lifetime guaranteed?

The Advanced Auto Parts in my area, don't offer a lifetime warranty anymore. I think they're on the way to where Parts America went. (Buh Bye!)

Refinish King

Is there any particular reason these units fail or is it just a coincidence that RC's 2nd sender failed? Should I be looking for an internal problem such as a plugged oil passage way? BTW, I noticed Advance has a 1 yr. warranty on the Sorenson sender.

it just one of "those things".... electrical transducers have a limited life... esp ones sourced from a DIY oriented parts store.. I've found NAPA Echlin electrical parts to be far superior to the crap that autozone and advanced sell. I just plumbed in a mechanical gauge on an A pillar pod in my '88 k2500 and have ignored the factory gauge since.

-Bret

It has some sort of guarantee but I don't plan on using it. I've got better things to do than replace junk with junk.

I could've ordered an AC Delco from gmpartsdirect if I'd been patient. I went to Advance because they carried AC Delco. At least until recently. I guess I was the only buying it from them.

Now I need to change the sender _and_ fish all the TFE tape shreds out of the fitting. Who was it told us not to use that stuff? :-)

-RC

R.Clarke spam snipped-for-privacy@BlocKmindspring.com RTP, NC, USA

That's good info to have (re: NAPA vs Autozone/Advance). What type of pillar did you get for your gauge? Is it custom or a universal model?

Tim

So what should you use instead of tape?

Tim

PTFE Pipe Dope:

Put the PTFE tape a few threads back and don't worry about it!

Refinish King

It's called the law of averages!

Sorenson was an A brand ignition company since the 30's, till the late 90's, when Standard Ignition bought it. For an outlet for it's second quality parts.

So if you're selling seconds, a few are bound to come back, and bite you in the ass!

Refinish King

coincidence

There isn't anything wrong with using the tape. It's just a matter of knowing how to apply it properly.

Ian

I used an Autometer Gauge Cage 2 gauge mount that I bought from Summit. I've been considering changing it out with a full A pillar triple mount for my 88 k2500 but I haven't decided on what the 3rd gauge should be... thinking a vacuum one would be cool.

-Bret