Problems with a Demon carb...maybe - Lateral-g Forums

Jr · #1 01-31-2011, 09:54 AM

I'm posting this for a friend.:

Since I have had my car running, I have never had a problem starting my car, even if it sits for a couple weeks....just a couple pumps on the gas peddle and it starts right up. The last three times I have attempted to start my car, I have been having trouble. It is cranking strong, but does not seem to be getting any fuel. I have been able to start the car by putting a little gas in the carb. Once it starts, there does not seem to be any issues.

Engine is 383 with Demon 750, no choke. Edlebrock mechanical fuel pump. Pertronix ignition with new plugs.

I pulled the air cleaner and with the key in the on position while pumping the throttle I am not seeing any fuel.

Any ideas?

Thanks

**Stuart Adams** · #2 02-04-2011, 07:07 AM

Don't know but I have had bad experiences with Demon carbs.

Vegas69 · #3 02-04-2011, 07:23 AM

After it starts, do the accelerator pumps then squirt fuel as designed? When a carb sets for some time, the fuel does evaporate out of the bowls and accel pumps. He may have a pump laying down on him. A fuel pressure gauge plumbed in after the pump would confirm this..

**Sieg** · #4 02-04-2011, 08:47 AM

I have a 650 Speed Demon, early design with the crappy base plate and an Edlebrock mechanical pump.

Even though the carb is basically junk when it comes to metering fuel I don't think it's a carb issue.

With a mechanical pump it takes forever to prime the system after the car sits for a while. The only upside is the engine has good oil pressure when it finally fires up.

I'm switching to an electric pump and different carb this season. (hint: I'm open to suggestions)

1962nova · #5 02-15-2011, 08:06 PM

This is my car that DJW is talking about.

Got it started today by putting a little fuel in the carb. Checked the fuel pressure at idle and it was 6.5. Drove the car around and it runs fine expect for a little stumble off of idle and going WOT at cruising speed. Pulled the air cleaner after I got back with the engine running and I am not seeing any fuel....

Any ideas?

Jr · #6 10-06-2011, 09:36 AM

Found a solution to the problem!

A very small set screw back out of the primary metering block... After finding that out, the problem was fixed.