Starts & stalls, hard start

[Keith Browning]

It is a 1995 PSD that will fire off on the first cycle of the they and then stall. Then it has to crank a little to re-fire. No DTC's, glow plugs draw 95 amps per side, fuel pressure is 45+ while cranking...

 

I have to let this truck sit for 2 days or more for this to occur but I checked the oil reservoir and the level was 2+ inches from the top which is low but not empty.

 

It has been a while since I have seen this. Is 2+ inches enough to suspect a leak or drain back? I could pull the covers and inspect for oil leaking at the injectors or suspect the pump. I replaced the IPR about 500 miles ago for no start condition when hot. The o-rings were chewed up but the customer opted for the IPR.

[MattB]

How low is the reservoir after the first crank and stall? All of them I have checked as normal have been full to the top. I found this in the PC/ED if it helps:

 

"The level in the oil reservoir should also be checked. Remove the inspection plug in top of reservoir and check to see if the oil reservoir is full (a reservoir that drains back after the engine has not been operated for a period of time can cause a hard start or a start and die condition). Filling the reservoir will allow the system to prime faster, facilitating starting."

[Keith Browning]

Yeah, I read that too and we know from experience that low oil levels in the reservoir will cause no-starts and this type of concern... the reservoir isn't empty. It WAS about 2-2.5 inches down the one time I checked. My thinking is that the pump still has prime and will start but then the oil aerates and the engine stalls. Then you only need to crank maybe 5 to 10 seconds and it then reluctantly starts, runs rough then eventually smooths out.

 

My experience with this has historically been EMPTY reservoirs. I last ran the truck Wednesday. When I get a break in the rain I will check it again before starting. If the level is low again I will fill the reservoir before starting to see it that cures the symptom.

 

The real problem is that if I am only losing a relatively small amount of oil detecting the source of the leak may be impossible to do... so which parts do you start looking at first? Which part am I going to tell the customer to throw at it... which may be the only way to figure this one out.

 

If I am going to guess I would like that guess to be an educated and thoughtful one.

[Bruce Amacker]

I suggest starting with some basics- what is IPR command at a hot idle? It should be 9-11%. What is MFDES? It should not exceed 14-16mg or it could indicate injector problems. I would check base oil pressure, also, on this one too, as a weak LPOP will cause this concern. If the LPOP is worn, it will allow the oil galleys in the block to drain out over time past the teeth of the gerotor pump. If the reservoir is 2+ inches low it starts and runs a few seconds on what's in the reservoir until it depletes. During this few seconds, the worn LPOP is struggling to get itself primed and fill all of the galleys in the block.

 

I've seen this before and the LPOP that fixed it, after the tech had changed everything else. I'm actually thinking you have two or more problems combined- the HPOP might be draining back some and the LPOP can't keep up with the initial demand from the lowered reservoir. Isn't life grand?

 

Deja Vu:

http://www.forddoctorsdts.com/forums/ubbthreads.php?ubb=showflat&Number=9127&page=1#Post9127

 

 

[Fredsvt]

Are the '95s the ones with the filter headers that lose the bypass valve for the filter? That little disc and spring that likes to fall onto the top of the filter and gets chucked at an oil change?

[LARRY BRUDZYNSKI]

Keith you said the oil aerates? This sounds almost like you have a bad gasket on the oil pickup tube in the pan.

[Bruce Amacker]

Are the '95s the ones with the filter headers that lose the bypass valve for the filter? That little disc and spring that likes to fall onto the top of the filter and gets chucked at an oil change?

 

 

Yes, but I've not seen that use his problem. Keith- make sure the filter bypass valve is in place.