Hi there,

I've got a 1989 F450 with a 7.3 diesel. For the most part it's been starting fine in cold and warm situations, but occasionally it will start normally, but then stall after a few seconds of idling. After that it is very hard to start. It almost acts as if it's flooded. I'm going to check the glow plugs for any that may be burned out. But that won't answer the stalling issue. After I manage to get it started again, it runs flawlessly.
Also, The glow plugs are on a manual switch that I had put in after purchasing the truck 10 years ago. I had gone through a couple of glow plug relays, so an automotive electrical shop suggested that I go to the manual switch. Should I have some sort of a plug controller put in, or should the manual switch be okay to continue on with?
My main concern is the stalling after it starts thing. It doesn't happen often, but when it does it's hard to get going again. Maybe air in the fuel lines? How do I remedy that situation?

Anyway, I'll put it out there to the masses. There always seems to be an answer out there.
Thanks, in advance, for all ideas and suggestions.

Regards,

Barry
bfuller@direct.ca

 

I think you are right about it being air leaks causing your problems. You might try replacing the return line from the injector to the injection pump with a clear line to see if you are getting air in the system. It sounds like air is getting into the filter and when you first start you are running on fuel in the injection pump and injector lines. But when that runs out you have air in the injection pump and lines and now have a hard start problem after the engine dies. Good luck, Jim

 

Is it doing the same from both fueltanks?

Fuelfilter ok? Drained out water from fuelfilter?

 

First guess is that if you install a "return line kit", you'll be good to go.
Second guess is that you are low on fuel.

 

Please post what the problem turns out to be. mine is doing the same thing. Thanks

 

At temps above 10 degrees,
Usually if the engine does not start or starts very hard, you are looking at a glow plug problem.

If the engine starts OK, then stalls a few seconds later, you are looking at an air intrusion problem.

The reason I said above 10 deegrees, I have seen it cold enough that my engine will stall several seconds after starting just becuse there is not enough heat in the cylinders for the fuel to ignite.
However when I reheat the glow plugs, it does start right back up when this happens.

 

If it ever got down to 10 degrees here, it would be headline news -- all the busted above ground water main backflow valves burst open covering the entire valley in several feet of water.

I miss real weather. Well, then again, not that much

Have you noticed if the stalling happens when you are low on fuel, or when the truck is pointing downhill?

If it's really cold now in BC, you can check Dave's theory out by plugging in the block heater for a couple of hours before trying to start. That should help with stalling due to the cold temps.

 

either tank? mine had a air leak did the same. but it didn't mater if i was low on fuel or not.

 

When mine stalls from lack of heat in the cylinders, we are talking 5 or 10 degrees below zero and not plugged in.

95% of the time when the engine starts, then stalls the problem is air in the fuel lines.

When it first starts doing this, parking with the front of the truck downhill usually makes the problem less noticable.
Parking with the front uphill makes it worse.