oil pressure

[JStoll]

I recently purchased an 89 350 series11 foot flatbed which Im building a service truck with I got it cheap with the blown getrag trans which I rebuilt (input shaft counter cluster bearings & synchros) & some body damage that Ill fix as well

when I went to load the service bed on I drove about 30 miles & when I came to a stop the stock guage droped fairly low & the oil light came on a slight blip of the throttle turned the light off Im gona put a mechanical guage on it but I was wondering if people had relief spring fatigue problems in these pumps as the engine sounds tight ( sounds the same before oil presure as after oil presure) I am a good technician but new to the cummins dodge any help would be apriciated IE: lowest acceptable idle hot oil pressure

thanks

JAK

 

[JStoll]

I forgot to say I just changed the oil using 15W40

 

[Philip]

Welcome to the TDR





The manual states that 6 PSI for curb idle speed.



At 3k rpm it is listed at 30-80 PSI.



Get a manual gage hooked up to make sure you haven't got a sending unit going out. If you want to test the sending unit. Here is a link telling how to do it.



https://www.turbodieselregister.com/forums/showthread.php?threadid=64844



Don't start on me about the drawing. LOL





What brand of oil?

 

[JStoll]

thank you soo much for your reply like I said I am a good technician(13certifications 20 years in the trade) but new here I hope to be helpful here as well as get the info I need for the new service truck Im building, Ill post pics here if I can of my progress with the truck

thanks again

JAK

PS I thought of the sender although both the guage droping & the light coming on may be an indication of actual low pressure Ill have to get a real guage on it & see

JAK

 

[JStoll]

chevron on the oil I believe?

 

[Philip]

They are two seperate circuits. But they both are controlled by a double sided sending unit. If one side goes bad. I don't trust the other side to much.



The manual gage will tell if you have any problems beyond a dought.

 

[JStoll]

I measured the OP today using an acurate guage today I use for testing & diagnostics the cold OP was 60 lbs & reving was around 80 when it was good & warm I got 37 lbs idlle & close to 70 lbs reving so it is the sender thanks soo much for your willingness to help

JAK