My 94 is losing prime overnight but starts beautifully when I have the block heater plugged in or have it sitting in a warm shop. Why would this make a difference? I have a new overflow valve on order but am not convinced that it's the problem. I can't plug it in all the time because I run a buncher out in the boonies and it sits cold during my shift. Also the other day a coworker started it for me when it was cold and he said it fired up perfectly. Any ideas?

Thanks

 

Hmmm...Interesting....I don't think it's losing prime...I think your grid heaters are not working...I've do some stupid things on my 95...Forgetting to plug it in at -15 and -20C...I would cycle the grid heaters a couple of times and it would start....Very crabby,but it would start...

I think your heaters are not working or are cutting out...

 

Do you crack the throttle a bit when starting?

 

Yes I throttle lightly and it helps eventually. But it definitely feels like its not getting fuel because it will fire a few shots, then spin, repeat until it finally gets enough to idle.

 

May have to check your fuel pressure...Maybe a weak OF or LP..

 

Need to make sure the shutdown solenoid is staying up after cranking then leaving the key on.

If it gets harder to start the longer it sits you probably have an air suction leak. Very common for them to suck air but not leak fuel, just looking doesn't always work.
By far the most common leak source is the 2' x 5/16 hose in red below.
More details here> http://www.cumminsforum.com/forum/94...m-writeup.html

 

Many thanks guys this is very helpful info.
I will replace the overflow valve first and go from there, if it ever arrives that is.

 

My bud is having a no start issue also. Where is the overflow valve?

 

Whats your idle at? If it doesn't happen when its warm/plugged in, losing prime is not your issue.

 

Well now I feel a little cheap.
This morning I cycled the "Wait to start" light twice and it fired right up. So I'll see if that keeps up.
Tate, with my gsk it idles at about 950 once it's warm. Which I don't mind because my high idle control involves a stick.

 

That's about right for idle....I think mine is around 850 to 900 when warm...

 

Whats it idle at cold. Depending on how the GSK is set, it will idle real low when cold and need some throttle to start. Loosen the springs, reset the idle. It'll fire up easier and less change between hot and cold idle.

 

Have you replaced the fuel lines?
Mine would do that if I parked facing uphill.
Facing downhil was not a problem.
Replaced the fuel lines and have not had a problem since (at least 8 years now).

P