Problem cranking Prostar when hot !!!

I have a 97 Prostar that runs great and cranks up fine when cold but once it gets hot it takes forever to get started, sometimes wont crank until cold. Anyone have any suggestions or fixes to the problem

[oxberger]

Debo, welcome to the forum. It could be several issues. The first things that come to mind are vapor lock or it may be a small crack in a vacuum line that reseals itself once cooled down. Is your engine carb of fuel injected? mrmastercraft has had some good insight to issues like this, so hopefully he'll come along and help out. By the way which engine do you have?

[rwassman]

Classic starter problems. Try an new starter and see if that helps.

[oxberger]

Originally Posted by rwassman

Classic starter problems. Try an new starter and see if that helps.

Didn't even think of this, but that's a good place to look at too. Before replacing the starter though check your battery cables going to and from it to make sure they're not cracked or corroded and that they're making a good connection. That may be an issue too.

Oxberger and others thanks for the replies, im not much of a mechanic but im about 4 hrs away from a reputible dealer. Anyway its a 350 efi 5.7ltr

[thatsmrmastercraft]

It sounds like you are dealing with some high resistance made worse by heat.

I would first clean the connections at the battery, ground at the block, solenoid and starter. Remove them and clean with a wire brush. If that doesn't take care of the problem I would remove the starter and take it to a reputable auto parts store, or better yet a starter rebuilder.

Likely this will lead you to the source of your problem.

Thanks Mr Mastercraft. The engine will turn over but it just wont fire. You think that could still be connection or starter problems ? Sorry for my mechanical ignorance.

[duffcam]

quote "The engine will turn over but it just wont fire"

it's not the starter then. do you operate your bilge blower at low/idle speeds (as is reccommended by MC)? you might even try leaving the engine cover open while you are sitting still, see if it's a cooling issue or a heat soaked fuel or ignition issue. my son had the same issue, we also increased the size of the rear vent on the engine cover

[JimN]

Originally Posted by oxberger

Debo, welcome to the forum. It could be several issues. The first things that come to mind are vapor lock or it may be a small crack in a vacuum line that reseals itself once cooled down. Is your engine carb of fuel injected? mrmastercraft has had some good insight to issues like this, so hopefully he'll come along and help out. By the way which engine do you have?

All MC motors since '94 have been injected.

[JimN]

FYI- 'crank' means "cause rotation" and 'start', or 'fire' is the correct word for the problem in this thread. This motor cranks.

High air temperature? Was it run hard immediately prior to shutting it off? If it's the first, open the motor box a few minutes before cranking it next time. You can also turn the bilge blower on for a few minutes, as recommended. If it's the latter, idle a little longer before shutting it off- not only will the motor's temperature be higher but fuel may drip from the injectors because of the increased line pressure that remains after the motor shuts off.

What else can you tell us about how it is run, maintained and any recent repairs?