Author Topic: 99 Cummins 300 oil pressure guage  (Read 685 times)

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Offline wvabeer

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99 Cummins 300 oil pressure guage
« on: August 19, 2017, 04:23:16 AM »
I just purchased a Newmar 300 Cummins on a Spartan chassis. The problem is the oil pressure gauge, it seems to run a around middle 40's then it jumps instantly to pegged then maybe down a little but never below 42. Any ideas???

Offline LJ2654

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Re: 99 Cummins 300 oil pressure guage
« Reply #1 on: August 19, 2017, 08:58:30 AM »
I know that on a gas engine that a pressure relief valve can cause an issue like this, but not sure on a diesel motor.

Offline ziggyh

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Re: 99 Cummins 300 oil pressure guage
« Reply #2 on: August 20, 2017, 05:33:32 AM »
I would put on a mechanical guage and monitor the oil pressure to see if it's a guage or electrical problem or if it is a sticky regulator in the oil pump.
ZiggyH

2007 Revolution LE
C9

Offline wvabeer

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Re: 99 Cummins 300 oil pressure guage
« Reply #3 on: August 22, 2017, 07:47:07 AM »
I would think if the sender was erratic there would be a check engine light or some other alert.

Offline antiqueclockservice

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Re: 99 Cummins 300 oil pressure guage
« Reply #4 on: September 06, 2017, 01:45:20 PM »
I think you might better call Cummins tech support at  1-800-DIESELS
Best,
Phil

Offline wvabeer

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Re: 99 Cummins 300 oil pressure guage
« Reply #5 on: September 11, 2017, 03:16:54 AM »
I notice after the gauges do the dance the oil gauge stays at 40 before I start.

Offline Brett Wolfe

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Re: 99 Cummins 300 oil pressure guage
« Reply #6 on: September 11, 2017, 06:12:07 AM »
I suspect the dash oil pressure gauge is a Spartan part, and may not even use a Cummins sender.

I would contact Spartan with your VIN and ask them how to diagnose a bad sender vs bad gauge.

Offline wvabeer

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Re: 99 Cummins 300 oil pressure guage
« Reply #7 on: September 12, 2017, 12:02:37 PM »
Spartan says it could be a Demux box, gauge or the connections. I'm looking into it.

Offline gerdutch

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Re: 99 Cummins 300 oil pressure guage
« Reply #8 on: September 24, 2017, 09:44:07 AM »
I suspect the dash oil pressure gauge is a Spartan part, and may not even use a Cummins sender.

I would contact Spartan with your VIN and ask them how to diagnose a bad sender vs bad gauge.

I have a  ISC 350, had a problem with the oil press sender, on the passenger side of the engine, rear of starter.,for which they were famous four. Changed it twice before it cured the problem you describe.