Engine starts fine when it is cold. Runs good. When it has been running a while and the engine is hot, then after being parked 10 minutes or so it won't start. It cranks just fine but won't fire up. Spraying a little WD-40 in the air intake makes it fire up every time.
Any clues as to what could cause this, or suggested diagnostics that could reveal the cause?
Thanks, Bunny
This sounds a lot like vapor lock. Fuel injected vehicles with an electric fuel pump don't exhibit this phenomenon. I don't know if diesel engines were ever affected, or if your '89 has electronic injection. I know that the gas engines after '86 were EFI.
HTH,
-D
Try this - carry some ice with you in a container, after the engine is hot and the "no start" condition exists, put a double handful or so of ice,wrapped in an old shop cloth, towel or whatever, on top of your injection pump. Leave it sit for a couple of minutes and then try to start it. If it starts, the problem is vaporized fuel in the injection pump, if not then good luck....
Dave D
>Hey Dave:
I left the ice on for ten minutes, and it started right up!
So where do I go from here?
THere are not big suprizes here, the engine is not getting fuel. It is either in the injection pump or the fuel pump feeding the pump. Also check fuel filters and check water drain for water in fuel that is boiling off to steam in fuel/pump when engine is hot.
Did you check for water in the fuel boiling off (which the ice would condense)
I'm really unclear on this. I put the icepack on the top of the injection pump, not the fuel filter. I don't see how condensing water that was steam in the injection pump would make it start. Wouldn't you just have a water in fuel condition then? And once it's started, it runs fine. Also, why would a spray of WD-40 make it start?
"Bunny Boy" wrote in news:1123209237.516971.218670 @o13g2000cwo.googlegroups.com:
Check for cracked fittings on the fuel rail. I experienced this on a 91
7.3. The kit for all the fittings, new hoses, hose clamps and O-rings was about $38. The evidence also included fuel smell from engine compartment as there was a leak.good luck, IowaHarry
If there is water in the fuel and it boils off in the hot pump, it will greatly expand and displace the fuel until it is purged with the engine running. When you ice it the water condenses and the water vapor lock is lost. Just a few drops of water is all it would take too.
Just to be outside the box, I'll suggest that your fuel has excessive alcohol in it. Alcohol allows water to mix with fuel, and might be found in fuel. The cure? A few drops of water. Crazy, huh?
Bill M
Real crazy, alchol can bind with fuel transparantly but when you add water to it it becomes less transparant. The last thing you ever want to do is to add water to diesel fuel.
Hey, Harry--
Not sure what you mean by "fuel rail."
I talked to a local diesel mechanic, and when I described the problem, he said it sounded like a worn rotor in the injection pump, which would require pump replacement or rebuild. ($500 + labor!!) I'm hoping this doesn't turn out to be the case. If it is, though, I'll be looking for a used pump, I think.
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