Cummins 870 oil pressure

[Jstephens129]

I have a couple issues that I’m dealing with on a Cummins 870 , I’m thinking they are possibly related .. first is on start up there’s no oil pressure for a good 5 seconds then it’s good and holds good pressure while driving and at idle , second is ive noticed air bubbles in the oil .. I’ve been a cat guy and first is my first isx I’ve had .. could it be pickup tube has a crack ?? Or oil pump loosing prime possibly ??or so mechanical oil pressure gauges just take a couple seconds to read Any help is appreciated

[Rawze]

Airated oil can tear an engine up fast, depending on how bad it is. You need to verify that is the problem and find out why. The pick-up tube, where it meets the oil pump would be one place to look at if it is indeed getting air in the oil. Another possibility is that your using an oil adative that causes/allows air to get trapped in the oil too.

[Jstephens129]

I changed oil couple weeks ago and the only thing I used was the gear oil additive

[Jstephens129]

It’s bad enough when I check oil I see bubbles on dipstick .. this engine has been a nightmare , I’ve been trying to get it into a good Cummins shop but everyone is out of state and booked up , just on here seeing if it’s something I can take care of myself before engine is destroyed .. are you referring to the oil ring on the pick up tube or pick up tube itself

[Rawze]

(12-14-2021 )Jstephens129 Wrote:  It’s bad enough when I check oil I see bubbles on dipstick .. this engine has been a nightmare , I’ve been trying to get it into a good Cummins shop but everyone is out of state and booked up , just on here seeing if it’s something I can take care of myself before engine is destroyed .. are you referring to the oil ring on the pick up tube or pick up tube itself

Just about the only places the oil system can suck air is at the o-ring at the pick-up tube where it meets the oil pump, or possibly at the pump itself where it mounts up to the engine block.

- That or someone has significantly over-filled the oil system, and it is getting sloshed around by the connecting rods/crank as the engine runs.

[Jstephens129]

Just ordered the o ring and pickup tube and will replace this weekend .. anything to inspect on the pump itself to maybe see if it’s sucking air on the pump itself ?

[Jstephens129]

You think I should replace oil pump since I’ll be in there ??

[Rawze]

(12-14-2021 )Jstephens129 Wrote:  You think I should replace oil pump since I’ll be in there ??

you never mentioned how many miles/hours on it, history of things, nothing. Its anyone's guess towards what might be needed to be done without proper information.

[Jstephens129]

Not sure , bought the truck from someone who decided putting a used engine in it without doing any kind of rebuild while it was out of the truck , the old engine threw a rod so they put a low mile engine in from a local in town , I was told it had 600k miles on it but haven’t hooked up to old ecm to verify , old engine had 900k before it blew .. I’ve been just trying to fix previous owners screw ups and it’s been a job .. I’m ready to throw in the towel if this oil pump and tube doesn’t fix it .. sick of messing with it and like I said previously no one around us is that familiar with Cummins, I’ve reached out to haggai but they are so busy they keep scheduling a month out and sound like they don’t really want to mess with it so I’m just trying to do all I can myself