Climbing steep hill, engine dies

[BigRedWeather]

For years my truck would pull a steep hill (steep = a hill that require 4X4) with no engine issues. In the past month I have been climbing a steep hill two times, and after about 30 seconds of doing so the engine just quit. It acted like it was getting no fuel, but the bowl the filter is in was full of diesel and the pump was producing a good supply of diesel. I could crank the engine for 5-7 seconds, but the truck would not start. Usually it start less than 1 second after I turn the key.

When I rolled the truck back to where it was aiming 90 degrees across the hill, and waited several hours, it started again.

Any ideas what could be causing this?


Thanks,


BigRedWeather

 

[Kevin 007]

With the twisting and different movements of the frame/truck going up those steep hills compared to regular driving, im betting there is a wire somewhere that is shorting out on something or up to no good. I don't know these engines well enough to guess which wire or which circuit may be involved but I think its a worthy guess. I had this happen on a few much older trucks.

Will it re-start once you level it out again?

 

[BigRedWeather]

It restarted after I rolled it back, sitting across the hill, and after letting it sit for a day. I just tried this again, and it wouldn't start.

 

[79jasper]

How's your oil and fuel levels?

 

[fordf350man]

i think that the powerstrokes wont start if the oil level is to low, not sure if its the obs style trucks or the more modern day ones, i say check your oil levels also

 

[lindstromjd]

i think that the powerstrokes wont start if the oil level is to low, not sure if its the obs style trucks or the more modern day ones, i say check your oil levels also

They won't. The 7.3 powerstroke (regardless of year) runs off of oil pressure. If the low pressure pump can't supply the high pressure pump, it shuts down because there's no high pressure oil to fire the injectors.

 

[OLDBULL8]

Check your fuses, if the fuel bowl heater shorted out it will crank, but no start. Don't know what number, but it's a 30 amp, supplies power to the PCM. Check your harness to the valve cover, drivers side, it will rub and bare the wires. Unless it's out of oil, climbing a steep hill, all the pan oil should be at the sump. The LPOP supplies oil to the HPOP, it should have tried to start, at least run for a second with extremely low oil.

Missed the start again, forget the fuses. Heat will give you trouble on the UVCH.

 

[BigRedWeather]

The oil is up to the full mark, both tanks are full, no blown fuses. I haven't checked the UVCH. If that were bad, it should cause problems on level or steep ground. Mine does great on all ground, except steep ground. Right now it is on level ground and no does want to start.

I'll check the UVCH next.


Thanks for the posts,


BigRedWeather

 

[Double-S-Diesel]

check fuel pressure, had one do just that before, had a bad pump

 

[BigRedWeather]

Thanks OldBull, the IPR was the problem. I am going to describe this so users of all knowledge levels can benefit from it.

The IPR threads into the HPOP and has a shaft that aims back at the tailgate. Three parts go on the shaft: 1) the collar that the harness connects to 2) a spacer and 3) a tin nut. When I got to my IPR tonight these three parts were in the valley of my engine, so the IPR wasn't being told by the wiring harness how much oil pressure to release to the oil galley that in turn would energize the injectors - so no fuel was getting to the cylinders even through the fuel system had plenty of fuel. From the looks of it the tin nut had been in the engine valley probably for a few months.

So, when I pulled that steep hill for the first time the collar slid so far back on the shaft that it wasn't able to send a signal to the rest of the IPR and oil pressure went south and the injectors didn't fire. When I rolled my truck back down and across the hill the collar slid back onto the shaft enough to send the signal to the rest of the IPR. Then my truck ran on paved roads for 2 weeks with no issues.

Two weeks later, the next time I was pulling a steep hill, after about 30 seconds, parts 1) and 2) slid back off the shaft, thus killing the engine. Rolling it back on level ground would not help it start this time.

I put the parts back where they belong and she's running like a top. I also learned, or at least it seemed that the connector on the collar has to be at 12 o'clock on the IPR. If it were at 6 O'clock, the truck wouldn't run.


BigRedWeather

 

[OLDBULL8]

Glad to hear you found the problem. Yeah, that tin nut has given more PSD owners fits than you can imagine.

 

[BigRedWeather]

Yesterday a very good PSD mechanic told me that Ford's spec on that tin nut is that it should be tightened finger tight, and then tightened 3/4 of a turn more with a wrench. I have put it on my calendar to check the nut every six months.

BigRedWeather

PS If it gives me more trouble I may weld a wire onto a regular nut that will prevent it from loosening.

 

[79jasper]

Bringing up some dead ones. Lol
If one took precautions to not over tighten, why can't we use a normal nut and loctite?

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