ofcmarc

On my way back to towm this afternoon my oip pressure gauge started acting funny. It would run a little low then it would bounce towards the 0psi mark then come back up to normal. It seemed worse if I was into the skinny pedal. Everything sounded fine and there was no difference in the smoke/power or performance. The low pressure light never came on.

I am thinking it's the sender. Anyone else ever see a pressure gauge do this? It's a new one on me.

I don't have a large enough mechanical gauge to verify my pressure but I will probly get one soon if the sender dosen't fix it.

TIA

wannadiesel

It sounds like the sender or a flaky connection to it.

ofcmarc

Thanks Wanna.

I kinda figured that. I'll hitch a ride down to the local NAPA this afternoon and pick up a new one the say they have one.

Free89W350

My trucks guage runs normal then low then normal then the light will come on. On a recent trip to NY (custom's and G1625S) it was fine then just went to low. I was talking to Greg and he said his truck did the same thing and it was a bad sender. I plan on just getting a mechanical guage rather than a new sender. I trust mechanical ALLOT more.

ofcmarc

I have an Autometer sport comp Oil press gauge sitting on my tool box that will be going in very soon. Just need to find a new sender for it as well .

Diesel Junkie

I hear that sending unit failures are common, and internal engine issues are not.

I had to replace my oil pressure sender once, and I have had to fiddle with the connector a couple times.

Pretty darn easy swap, and it was not too expensive either.

Funny though,
When i first got my truck the oil light would come on at idle when hot, but if I reved it up no light. Didnt have a tach so I thought the idle was too low.... kept turning up the idle until it was at like 1500.... Figured out that was stupid after I put the replacement sender on it.

ofcmarc

Replaced the sender last night and it seems to have fixed the problem. It was kind of a PITA dause the fuel filter (I use the long ones) was in the way and I barley had enough room to swing the channel locks to loosen/ tighten the sender.

Does anyone know where to get the senders for an Autometer gauge? I have an Oil pressure and Water Temp gauge I want to install but I'm missing the senders.

91.5 beater

My guage did this along with the water tem and it turned out to be those ground wires on the mount for the grille , look for the wires that are just in fornt of battery, there is a screw that comes loose that connect the wires ground, that is what caused mine to jump around anyway,

ofcmarc

Thanks for the tip! The gauge still fluctuates a little and it didn't before. I'll check the grounds.

A real oil pressure gauge is going in very soon.

TruckU

So what is "normal" oil press for a CTD?

ofcmarc

So I got the new gauges in and I've been watching the oil pressure.



At idle it holds ~37-38psi when it's warmed up. runing down the road, it holds well over 65psi.

Seems that the idle pressure used to be higher.

GIT-R-DONE

Mine when warm at idle (mechanical gauge) is around 30, running down the road, 60-70 lb.

My dash gauge for oil pressure works only when I have my foot in the throttle, but at idle, the low pressure light comes on and the gauge in the dash goes completely to the left, (0).

wannadiesel

That sounds like plenty of oil pressure. Cummins minimum spec for hot idle is 10 psi, and minimum at rated RPM is 30 psi.

ofcmarc

Thanks guys.

The stock gauge started acting funny the it seemed to read low compared to what it used to run and got me a little worried.