worse when warm

[my81C10]

81c10 305 4bbl Holly Carb. So I been having a few issues lately and stuck again so I'm back here. So I just did timing where It seemed to run the best (no backfire from either end) also did oil change and changed tyranny fluid. So my issue is it has a loss of power when it warms up. If I go to the store come out and start it, its hard starting. Like it wants to start but wont kick over. I have to hold gas peddle half way down then it kicks over a second or two later. Then driving it lacks power. Rpm s sound fine no big stumble. At a stop it idles a little rough. Where do I start looking?

[geezer#99]

Do you have a heat spacer under your carb?
Could be fuel boiling and making it flood a bit.

[my81C10]

Honestly i have no idea

[geezer#99]

Take a pic of your carb with the air cleaner off from front and both sides.

[Angryman117]

Sounds like the timing is advanced too much. If the carb is vapor locked the engine should turn over fine, just won't start.

[cdowns]

check to see if the choke is stuck closed

[my81C10]

[geezer#99]

Nice pics and you have no heat riser.
If you want one they make them in aluminum, wood or phenolic plastic. A 1 inch 4 hole would work.

Check summit racing.
http://www.summitracing.com/int/sear...etor%20Spacers

[geezer#99]

Do a simple test. Warm it up and drive like normal and get it up to full operating temp. While idling look inside the carb. You shouldn't see any raw fuel.
If you do the float is too high or the fuel is boiling in the carb.
Shut it off and look in the carb again for any raw fuel. Same as before. Shouldn't see any.

[mongoose]

uhm... what is your timing set at?

there's a huge difference between good, bad, and getting it not to backfire.. i'm assuming you're still in the bad zone. could be a small vacuum leak starts runnning lean once the choke is open... does it surge?

[storm9c1]

Right, timing it by ear works but -- every time I time an engine by ear and then put a light on it, I'm always way too advanced. But it always sounds so strong! Yeah, put a light on it, might need backed off a little.

I also wouldn't rule out a carb problem. I always run spacers on my carbs. But let's do timing first since that's a mystery right now.

[familyfast64]

I agree, timing first, and just to provide you with a lil extra confidence, in my 355 I used to maintain, spacers, heat shields, wrap for headers/spark plug wires , starter, fuel lines run away from coolant lines, choke set right, good cooling system, all easily done and very important. Irs funny cause a car runs better warm but worse hot. I can't imagine the 305 making much heat but it don't take much for fuel to boil if it's laying on coolant lines, and the block...

[cdowns]

having that delux rubber gas line is a great way to burn your truck down to the ground

[storm9c1]

Originally Posted by cdowns

having that delux rubber gas line is a great way to burn your truck down to the ground

+1. I just didn't want to hit a guy when he was down...

Hopefully he will get to that later... right?