Why am i having trouble starting when warm?

[Midcont]

Originally Posted by cycleguy55

When you write 'warm' do you mean 'hot' or normal operating temperature?

Do you have an electric fuel pump or mechanical?

At this point my guess would be vapor lock or fuel percolation. The area around the carburetor is hot enough to vaporize the fuel.

One solution is an insulating spacer between the carb and intake manifold. Electric fuel pumps seem to be less prone to this than mechanical pumps.

Probably worth a few minutes to check out this thread: Holley hot stop fuel perc issue

I believe it's mechanical. Will need to verify.

Originally Posted by LMH

Vapor lock on a carburatored engine? Is there a spacer or heat shield between the carb and manifold?
Larry

It's a Rousch engine. Not modified so I doubt it.

Originally Posted by ACademic

On a warmed-up engine, you should only have to depress the gas pedal slightly (maybe half way at most) and turn the key (no pumping). Otherwise, you risk flooding it. If that doesn't work, then you might be boiling the fuel out of the bowls. If the starter is cranking the engine slower when warm, that could be a whole different issue (weak ground wires, thermal expansion of an older, non-high torque starter, not enough CCA from the battery, etc.).

Tried depressing, not halfway but maybe 1/4. I'd say its cranking as quickly warm as it does cold. It's all stock SPF components, mid 2k chassis number.

[jhv48]

Had the same problem with my roush engine when new. Put a 1/2 inch phenolic spacer under the carb. Problem solved. No more percolation.
Also, during hot restarts, use no throttle. Should fire right up.