I'm having a miserable time with my E350. Seems to be oil related. Starting is the main issue. Once running, it rarely quits. I have changed my lpop for a Melling, and got only a slight improvement. The hpop reservoir empties itself sometimes - even with the Melling.

Another oddity it does is if you downshift for a hill i.e. revving hard in 2nd, and then you pop it into D because the road is flattening out, it quits. Has always restarted for me before I need to pull over, but get worrying with up to 10 seconds of cranking to restart.

I have manual glowplugs, mechanical oil pressure gauge, and a mechanical hpop gauge.

When 'warm' the readings with the old lpop are:
hpop: 600psi idle, 1300psi revved
lpop: 5psi idle, 45psi revved

readings with Melling lpop:
hpop: 600psi idle, 1300psi revved
lpop: 10psi idle, 80psi revved

It seems like my lpop can't keep up with my hpop.

This serial # is not supposed to have a de-aeration valve (that can fall out). And my oil filter base has its relief valve retained by a snap ring. I'm not too sure where else I can be losing oil pressure.

Any ideas?

 

Cracked oil pick-up tube??? I know this happens and I believe there is a test for this.

 

WOOOOOhoooo...

Your low pressure oil pressure is 5psi when warm?

I would bet you have a bad pick up, or a worn or grooved front cover...

 

10psi idle now with the Melling pump. That is a driveway warm too... not a driving warm.

No groove. The timing cover looked good.... and so did the old pump that came out.

 

Wait, so if you let the truck sit over night your HPOP res is empty in the morning?

 

No, that hasn't happened. Its all the cranking.... if it's having a particularly stubborn go at starting, the reservoir runs out.