I have a 85 ramcharger with Edlebrock 600 carb seems too much fuel drains back to tank as first start up takes a load of cranks. Also there is still a vapor lock thing going on , I have rerouted the fuel line and is rubber. Timing is set at 12. The transition between idle has much stuttering, have almost got it out but still there, I suspect thats why it was sold. I think rebuild carb. Engine runs fine has great oil pressure and in 4 months has used a half quart oil which think leaked out. it sat five years. Fun damn truck to drive just need as much power as I can get out of it.

 

IMO, I doubt the fuel in the carb is siphoning back to tank if that's what you're thinking. Even if the fuel pump is allowing back flow the air gap between the needle and seat and float level should only drain the line. I'd suspect the floats are not set properly, fuel in the carb is evaporating, leaking internally, or a combination of any of these.

 

So the RC did it twice again today acted like vapor lock and quit . So I pulled of the return line and gas shot out mucho pressure, so I thought fuel filter plugged up so put on another one , ran like a champ for about 6 miles then lost power and stopped. Pulled off the return line again gas came out not so much under pressure. So I ran it around in my head and thought check the gas cap, just bought a new non locking vented cap. Well it wasnt venting properly seems it is a spring loaded chinese affair wasnt venting at all. So being a old Harley go fast guy I drilled out the cap to vent the tank properly. Old mickuni race trick. Weel see what else is wrong with this carb. later.

 

well it turns out it was the fuel filter I replaced the three legged filter with a regular in and out filter and the problem seems to have gone away starts easier and runs way better. This RC is a 85 which has all the pollution control stuff has been removed
. So moral of the story check if chinese fuel caps vent and replace the filter with a regular one. The combination sucked all the fuel out of the carb making for hard starts and poor runability.