I have a 6.2 liter diesel Chevrolet Suburban and it starts right away when the engine is cool. However, when the engine gets warm (not necessary hot) the engine will not start. Does anyone have any ideas what this may be? It will start and run if we use starting fluid! The engine runs good when it is started.

Jerry

hows your cranking speed? weak batteries/starter can cause a lot of hard start hot complaints, its should be 200 or close to that atleast. other than that...pretty much Hydraulic Head and Rotor time for your injection pump.

This is a classic symptom of a week pump. It's time for an injector pump rebuild.

Hi, I have a mechanical injection 6.5 (essentially the same as a 6.2 just a smidge bigger) and it has the exact same problem. The problem is the head gets worn on these pumps and when they are warmed up the fuel is thinner and they won't pump.

Ideal solution: New head for the pump. Be wary of just a rebuilt pump though because most rebuilders don't touch the head.

Poor man's solution: 1 liter of water poured on the head of the pump, she will start up no problem.

I discovered this when I was in a crunch and didn't want to leave my truck parked at the service station.

Yeah...while the ol bucket of cool water trick may work a time or too...its really not a good habit to get into. cold water will make the head shrink and fit tighter to the rotor alright, but get it too tight and you could sieze the head up.

you raise a good point, though I don't think 1 liter of water would be enough to cool things to the point of siezing if the motor is not running. If it is running that is a different scenario that I wouldn't play with.

another 'quick fix' solution that I have heard of guys trying is adding about 5 percent oil to your fuel. This is supposed to thicken the fuel enough so that it will pump. Some guys use ATF oil or engine oil but I've heard 2 cycle oil is best. This is also not a great solution as you might find your old diesel is even smokier than usual. I wonder is anyone has found biodiesel cured this thin fuel problem.