Engine/Transmission (1994 - 1998) No oil pressure

[Budro]

I have just completed overhauling my 96 12v at 389K. New brgs, rings, gaskets, seals, head worked, new valve springs, new HD clutch, DDP stage 1 injectors, etc.....



At start up I was waiting on oil pressure to come up before I allowed fuel to the injectors. Allowing the starter only 15 sec starts and 1min rest. After 5 tries, still no oil pressure. (I filled the oil filter full before putting on engine. ) I installed a mechanical gage just to be sure and have disconnected the turbo oil pressure line at the turbo to check for oil flow.



Anyone have any idea how to prime the oil pump? Through the turbo outlet on the oil filter housing?



Jerry Jones

Graham, TX 96 extended cab, 4x2, 5spd, 3. 54, long bed, Ispro boost and temp, trying to keep it close to stock.

 

[GAmes]

That might work. I just started mine, gritted my teeth listening to the valve clatter seemed like forever. I had motored the engine over to get fuel from the injector lines. The pressure finally came up and the noise went away. It was in reality probably 5 to 10 seconds. I think prefilling the IP and the turbo is more important.

 

[champspa]

put a gauge on your filter bracket , mine has a pipe plug on top , that will show real pressure not that electronic pressure .

 

[radixr]

Try cranking longer. I have to crank for almost 30 sec. before the dash gauge shows pressure.

 

[Budro]

Thanks to everyone for their reply to my delima of no oil press during cranking.

After talking to a former Dodge diesel mechanic, I am back in the land of diesel fumes again. He suggested to keep cranking for at least 1min or until it cranked - which ever comes first. I primed the injectors with a 15 sec crank, tightened all the injectors and after saying a short Prayer, I started counting and cranking. At 12 sec it roared to life. Kinda reminds you of a new baby's first cry! Oil press went straight to 40 on the dash gage and 50 on the mechanical. Everything sounds good and no leaks, temp normal. Tomorrow evening I'll get the bumper back on and take it for a test drive.

Thanks again for you help.

Jerry Jones
96 SLT Extended Cab, 4X2, 5spd, 3. 54, Ispro boost and EGT, Fresh air intake, overhauled at 389K, DDP stage 1 injectors, otherwise stock

 

[Budro]

Thanks to everyone for their reply to my delima of no oil press during cranking.



After talking to a former Dodge diesel mechanic, I am back in the land of diesel fumes again. He suggested to keep cranking for at least 1min or until it cranked - which ever comes first. I primed the injectors with a 15 sec crank, tightened all the injectors and after saying a short Prayer, I started counting and cranking. At 12 sec it roared to life. Kinda reminds you of a new baby's first cry! Oil press went straight to 40 on the dash gage and 50 on the mechanical. Everything sounds good and no leaks, temp normal. Tomorrow evening I'll get the bumper back on and take it for a test drive.



Thanks again for you help.



Jerry Jones

96 SLT Extended Cab, 4X2, 5spd, 3. 54, Ispro boost and EGT, Fresh air intake, overhauled at 389K, DDP stage 1 injectors, otherwise stock

 

[GAmes]

Oil press went straight to 40 on the dash gage and 50 on the mechanical.

This caught my interest. I just installed an EV2 oil pressure gauge. I put the sender in the open port on top of the oil filter. When the engine is cold the dash gauge is a little over 40 (50?) but the Isspro is at 75 A little rpm and the gauge is pegged at 100, while the dash is at about 55. I am thinking pre and post oil pressure regulator. Just wondering what you show on the mechanical at 2000 rpm.

 

[Budro]

Mr. Ames



I too was hooked into the 1/8 NPT port on top of the oil filter for the mechanical guage. When it started the dash gage held at 40 and the mechanical when to 75 at idle! I was afraid to state this orgionally cause I thought the old gage I was using may have been off. I have not had it above idle yet and have removed the mechanical gage, but I may hook it up just to see what happens. Give me a day or two to get things back together and I'll let you know what I find out. Best I remember there is a relief valve in the oil fiter. The factory diagram shows the oil from the pump going straight to the cooler then to the filter. The 1/8 port is probably between the pump and oil filter relief valve. If I had another gage and connections I would tee into the oil line that supplies the injector pump/vacuum pump and see what is going on there. This is on the same oil galley as the dash pressure guage. Be interesting to find out.



Jerry Jones (Not of the Cowboys!)

Same as above.

 

[GAmes]

With the engine installed in the truck it would be a bear to plumb a port into the IP/VP supply line. Maybe a T for the stock pressure sender? I wonder if there is a more accessable port.

 

[GAmes]

Dang!! I was hoping someone would jump in with an alternate sensor port. I took a look at the '98 12 valve I have in my garage. It has TWO plugged ports besides the ports for the IP/VP oil line and oil pressure sensor. I felt around the side of my block, but could not feel any on mine.

 

[Budro]

I hooked up a 200lb gage to the 1/8 NPT port on top of the oil filter, ran it to the windshield wiper for a tempoary setup. Cold startup at idle, 40 on the dash, 105 on the filter! After reaching operating temp at idle, 35 on the dash, 55 on the filter. 5 minutes after startup, at 2K RPM the filter reached 110, and the dash 40. After warming up things seemed to settle down. One thing for sure - The oil pump works!

Maybe some of the older Cummins gurus can tell us what is happening. This doesn't seem to be hurting anything, just makes a fellow wonder.

Jerry Jones
Graham, Texas

Info above

 

[Budro]

I hooked up a 200lb gage to the 1/8 NPT port on top of the oil filter, ran it to the windshield wiper for a tempoary setup. Cold startup at idle, 40 on the dash, 105 on the filter! After reaching operating temp at idle, 35 on the dash, 55 on the filter. 5 minutes after startup, at 2K RPM the filter reached 110, and the dash 40. After warming up things seemed to settle down. One thing for sure - The oil pump works!



Maybe some of the older Cummins gurus can tell us what is happening. This doesn't seem to be hurting anything, just makes a fellow wonder.



Jerry Jones

Graham, Texas



Info above

 

[GAmes]

Quite a difference. Once I am up to operating temps I am still showing 60-65 on the Isspro, just over 40 on the stock gauge at 2000 rpm. The big difference is at idle, 20-25 on the Isspro with the stock gauge still in the normal arc. I am giving a lot of thought to repositioning the Isspro sensor. It looks like my tach while I'm going thru the gears:-laf

 

[DWeaver]

I plumbed in my el cheapo mechanical gauge at the same port as the stock sender, just used a tee and some adapters. It was interesting getting it plumbed with the engine in the truck.



At start up dash reads 40 psi and the mech. reads 75 psi.



I have been having some fluctuations with the dash gauge. Yesterday when it dropped to 0 psi and stayed there was when I figured I better see what a mech. gauge says about the situation.



Have to drive it more to get more info.

 

[GAmes]

After all these years I finally installed a fuel pressure gauge, and used a grease gun hose for the sender. It occured to me that the hose fitting is the same size as the oil pressure sender (1/8 NPT). Two problems. Installing it so that it doesn't look too redneck and how to get a wrench on the fitting without removing the PS pump.

 

[BIGNASTY]

People laugh but this is why from DAY 1 I have had a pre luber on my truck. It has been said that 90% or ware is done at start. I had one on a used truck that I bought and went to change the rods and mains at 100K and they looked really good. JMO When I start its got oil Pressure BEFORE IT EVEN CRANKS TO START!!!!!!

 

[surfbeetle]

I plumbed in my el cheapo mechanical gauge at the same port as the stock sender, just used a tee and some adapters. It was interesting getting it plumbed with the engine in the truck.



At start up dash reads 40 psi and the mech. reads 75 psi.



I have been having some fluctuations with the dash gauge. Yesterday when it dropped to 0 psi and stayed there was when I figured I better see what a mech. gauge says about the situation.



Have to drive it more to get more info.

I know I'm reviving a 5 month old thread, but my dash gauge decided to go to 0 when accelerating today so I was wondering what you found out when your gauge dropped to 0. Did you have to change your pressure sender? I changed mine to a Napa unit several years ago when I broke it repairing the vacuum pump. It was a Sunday and Napa was the only one who had one. So I have not had the experience of the gauge/sender dying a natural death.

 

[CharlieFoxtrot]

My stock gauge was reading ~40 most of the time but would drop to near zero on acceleration. I was pretty sure the sender was the problem so I ordered a new one @ Genos but also hooked up a mechanical Auto Meter gauge at the oil filter.

Like a couple of previous posters mentioned, I am getting ~60 psi at idle, ~75 at 1800, and 90+ at higher RPMS. That's with the engine fully up to temp on an 84* day. Pretty alarming! We must have some tough filters!

When I change the sender, I'll set up some sort of Tee and put the Autometer gauge there permanently. I'll update this thread with pressure readings at the new location.

 

[Joseph Donnelly]

A zero reading on the gauge is usually indicative of a bad sending unit, or bad wiring connection there. BTW, I coat the rotors with grease when assembling a new engine so the pump will pull oil quickly. V8 gassers are easy to prime because their pumps run off the distributor gear; just spin the oil pump driveshaft before installing the distributor. The Cummins pump is geared to the crank so there is no easy way to prime the system.