Hey guy's I'm stumped. My 93 cranks and starts fine when cold or when it's below 50 degrees outside.But when the air temp is above 60 degrees and the truck is hot it cranks but will not start.It will start with starting fluid and runs great.engine has 281000 miles.Low compression?Injection pump?Any ideas? Thanks!

 

n.c.moutainman;
I'd run a compression check, from what you describe I'd say she's low on compresion.
ramguy

 

I'd rule out any air leaks in the lines first. Maybe when it's cold the lines ar contracted enuff to slow the leak?

 

Mine didn't start on me yesterday after I parked it at a friends house. Jiggled the wires on the shutoff selenoid and it fired right up.

What you describe is the way an old 6.9L ford my dad had was. We started it with propane. Thing had very low (lower than usual for a 6.9L) power as well.

would start fine when engine cooled down.

 

Whats the preferd method to check for air leaks ? presurize the lines and use soapy water? Guess I needed to buy that commpresion tester anyway

 

Just start by checking the condition of the rubber line sections. Are they drying up? They don't have to be leaking fluid for the pump to suck air into the system. There are a couplt short sections at the tank too. I ran new hose and bypassed all the old lines. Like andy said, check wires too, but it wouldn't hurt to take a look at the lines anyway, the issue is bound to come up sometime anyway. While your at it, you should track down every connection you can find and clean and grease them. You can put the truck in an airlock for 15 years and still get corrosion from the mixed metals used.