Hello All,

My dad and I are in the midst of putting a 1983 Dodge D250 back on the
road. Originally it had a 318 (5.2L), V8 but at some point in its life
the V8 was replaced with a Slant 6. I believe the engine is an early
80s version as it has the electronic spark control and EGR.

The truck originally had idiot lights for the engine temperature and
oil pressure, these have been swapped out for the factory gauges. The
engine temperature gauge works great, the oil pressure gauge does
nothing.

The oil pressure gauge has been tested – goes to maximum when the
sensor lead is grounded. The engine oil pressure has been tested using
a mechanical gauge – shows ~30 psi at idle. I'm suspicious of the new
sender unit, a Standard Motor Products model PS59. With my Ohm meter
it shows high impedance when the engine is off (expected), and
somewhat lower values with the engine idling (also expected). But the
gauge shows nothing. I can not find test values for the sender
anywhere. The factory service manual is useless, only shows the
'factory tool' (box with a switchable resistors), that tests the oil
pressure sender and fuel gauge sender.

What brand / model of pressure sender are you using????

Looking forward to your reply.

Thank you and take care,
K&Sons

The correct sender for the gauge is Standard motor products PS-59. With the idiot l;ight
With the light, either PS-133 or PS-139 depending on thread.

_________________
Charrlie_S
65 Valiant 100 2dr post 170 turbo
66 Valiant Signet 170 nitrous
64 Valiant Signet
64 Valiant 4dr 170
64 Valiant 4dr 225

Hello All,

First, sincere apologies for the delayed reply - conflicting priorities.

Picked up a new sender unit (Echilin), that looked exactly like the new Standard Motor Product currently installed in the engine.
Fortunately the new sender solved the issue! Factory gauge now registers decent pressure values - Hooray!! Can't recall the last time I encountered a 'defective' new part.

Many thanks SL6 Racer for the feedback.

Question - I wanted to remove the oil pressure relief valve for inspection, polishing (Crocus Cloth), and installing a shim under the spring. I was able to remove the cap and spring but no luck with the valve. This is a 1983 Dodge D250 pick-up. The motor mount is right beside the oil pump which prevents one from straight access to the relief valve bore. Tried using a piece of bent wire (plastic sleeved to prevent scratching the bore), but no joy. Any thoughts on how to get this out without removing the motor mount?

BTW I was able to add a 1.5mm (~ 0.60"), shim under the spring.

Looking forward to the feedback.

Thank you and take care,
DadTruck

Defective "new" parts are becoming more and more common these days.
I recently swapped over to a fresh engine in my truck, and among other things that I replaced was the temp sending unit. Like yours it was bad out of the box.
It showed "pegged hot" when the engine was stone cold, hadn't even been started in a few days. I wound up taking the one out of the old engine, screwed it in and all was good again.