Starting issue 7.3 NA

[brinkmanj]

I searched and couldn't quite find my issue, so here goes...

'93 F250 7.3 NA, 166k miles all stock. 9 times out of 10 when I start it for the first time of the day, it will start, then immediately stall. If I rev it up and hold it at around 2k for a few seconds it will usually stay running and then idle fine at high idle. On the restart after stalling it cranks a little longer and then starts and runs. After the initial start it will start every time after that until it sits overnight or longer. I have replaced return line caps and o-rings due to some leaks and this problem has not changed a bit. Fuel system seems very tight and truck runs perfectly after it starts. I have not checked fuel pressure at the filter head because I don't have access to a fuel gauge. Brand new beru plugs 2 months ago and glow plugs and relay work correctly. It seems to be getting better as the weather warms up but it hasn't been hot out long enough to say for sure. What do the experts think?


Thanks for any help.

 

[icanfixall]

Fuel is leaking down somewhere. Did you replace the seals called olives in the fuel line from the filter to the injection pump yet.... Those can be bought at any pump rebuild shop...

 

[hesutton]

I agree with Gary. It seems to be a fuel/air leak. Do you smell diesel fuel at all under the hood? Any "wet" fuel connetions, caps, injectors, lines?

Fuel/air leaks can be a real bear to track down sometimes, but what you are decribing is classic for air intrusion.

Heath

 

[plywood]

I'd check all around the filter and filter head too.

 

[brinkmanj]

Thanks guys, I have not been able to find any leaks and I was thinking maybe a fuel delivery issue from the lift pump on a cold start but what you're saying makes perfect sense. Looks like I have a leak to find!

 

[Compu Doc]

Two things could be going on.

1. Bad lift pump.
2. Depending on temperature lack of anti gel.

Assuming it is not temperature I would check the lift pump.

I had the lift pump go on mine and would start great in the morning sometimes stall and then cranking to get it running again. Sometimes during the day it would not start if left for an hour or so after parking.

As for the anti gel, when it was cold this past winter my truck would start then stall right out if the block heater was not plugged in. If the block heater was plugged in long enough prior to starting it was not an issue. Their was no anti gel in the tank.

When I did put antigel in the tank (double dose of power service) it would start and stay running without being plugged in and at temps around 10 degrees.