[Phantom Italian]

Hey everyone!

I replaced my oil pressure sender for the gauge yesterday and I'm a little concerned. I read that to tighten it you shouldn't go very far, maybe a quarter to a half a turn. So I did that, and it's not leaking. But my oil pressure gauge started reading differently and I don't know whether to trust the gauge or not. Usually when I cold start it it sits at the bar after 55psi and before 110psi. Now, after replacing the sender, when it idles it's about the same, but when I drive it, it's just a hair away from the full 110psi. If I drive really slowly it reads lower. Once the engine warms up, it's fine. But It still reads a little higher than it did before. Is this normal, or is it something wrong?

 

[Milanoverde]

Doesnt sound bad to me, but these gauges are notorious.

 

[Phantom Italian]

Doesnt sound bad to me, but these gauges are notorious.

Hmmm. Now I am questioning whether it was working correctly in the first place. Seems kinda risky to just leave it without knowing how accurate it is.

Is there a known baseline where the gauge should work?

 

[DPeterson3]

When I dealt with gauge/sender problems with my 78 Alfetta GT, I discovered there are several senders and ambiguity about what fits what?

After one false start, I got what I believed to be the right sender. First step was to hook up a mechanical gauge with the brass tubing coming in the right vent window. Drove it around making notes on both cold and fully-warmed readings. Then after it all cooled down, I installed the sender, plugged in the wire, and took it for a drive.

Bingo! All good.

I’ve still got the first, incorrect sender. Supposedly for Veglia, but not sure which.

 

[Milanoverde]

Hook up a mechanical gauge per above.

 

[DPeterson3]

Do any of us really need GOOD reason to buy a new tool? Nah. Me neither.

 

[alfaparticle]

When the engine is hot and at higher rpm notice the oil pressure. If the gauge is accurate it will be about 50 - 60 psi.
High pressure when the engine is cold is not unusual.

 

[Phantom Italian]

Ok. I wonder if maybe my sender is incorrect? My old one was taller than the new one and looked slightly different. I'll definitely check out the mechanical gauge solution.

 

[alfaparticle]

Mechanical gauges only have to be dropped or banged around a bit for them to lose their accuracy. Get a handful of tire pressure gauges and you will be lucky to find two that read the same.

 

[DPeterson3]

I wouldn’t change your car permanently. It’s only to check the accuracy of the sender/electric gauge.

Most, but not necessarily all, Alfa senders have a 10mm STRAIGHT thread, not a pipe thread. Summit Racing offers a 10mm straight X 37 degree AN adapter. You can make up a copper line or flexible AN hose to bring the oil pressure into the cabin.

 

[boxandboat]

I hope

I wouldn’t change your car permanently. It’s only to check the accuracy of the sender/electric gauge.

Most, but not necessarily all, Alfa senders have a 10mm STRAIGHT thread, not a pipe thread. Summit Racing offers a 10mm straight X 37 degree AN adapter. You can make up a copper line or flexible AN hose to bring the oil pressure into the cabin.

Yes I think and hope that thsi fixes the issue. Good luck to you bro!

 

[Phantom Italian]

Ok, so I haven't gotten around to getting the mechanical gauge, but I also tried replacing my sender for the oil pressure light and, unfortunately, I have a coarse threaded sender.

Anyone know where to get a coarse threaded sender? Centerline is out of stock and it seems they are the only people who tell you which is which.