Print Dad 58 Report post Posted September 25, 2022 Hello all, once agAin I turn to this forum for thoughts and advice. I have been busy with several projects but a minor but important issue has me stumped. the car 70 Mach 1 351 c the carb about 8 years old Holley 650 vac secondaries when the car sits for about a week it takes a lot of cranking to start unless I give it a 2 sec shot of starter fluid i have checked the choke and it is working great and fully adjusted i have a clear “fram” filter before the carb,,,, it stays 3/4 full i checked and there is NO leaks at accelerator pump, metering;g block or anywhere outside the carb. this leads me to think possibly a bad power valve ??? not sure if they leak into the manifold. when the car starts… she runs about as perfect as could be expected. no-skips , buck, backfire ets. My wife thinks I’m nuts…but I would like to let car sit and start right up after 3-4 weeks if I start after 2 days I pump the gas once to set check turn key and it fires i know I have to remove sight bowl screw to verify that the bowl is empty I appreciate thoughts and opinions sam Quote Share this post Link to post Share on other sites
Mach1 Driver 538 Report post Posted September 25, 2022 It could be the valve, but one of a few problems with Holleys is that the fuel bowls are hanging out there on the ends and use gaskets to seal them up to the metering blocks. Some guys say they have to replace the blasted things yearly or they leak, especially since the addition of alcohol to the fuel. It sounds like its time to change the gaskets Sam. First I would replace the gaskets, but Instead of cranking for a long time it would be better to use one of those oil squirt cans filled with gasoline and pump it down the bowl vents till working the throttle gets the boosters to squirt. The wiring to the solenoid is actually under size and if you crank it for a long time it has been known to smoke the wire, according to Midlife, who is our premier harness fixer-upper. 1 Print Dad reacted to this Quote Share this post Link to post Share on other sites
Print Dad 58 Report post Posted September 25, 2022 Hello Mach 1 Driver, thanks for the thoughts and advice,… I will replace the gaskets but I don’t ever see or feel gas on the outside of the carb. I may also try putting fuel in the vent tube. just so you know when I crank the motor I only crank for about 5-6 seconds, the wait a few seconds then repeat. I never continue to crank long thanks for the help… best of luck with your dream car sam Quote Share this post Link to post Share on other sites
bigmal 222 Report post Posted September 30, 2022 I've been chasing ths problem for years. I first fitted a fuel shutoff valve which is only open with power on. (Also for anti theft). This made no difference. I've now added an electric pump at the tank. Strangely it is still difficult to start after a couple of weeks. Maybe time for EFI :) Quote Share this post Link to post Share on other sites
unilec 57 Report post Posted September 30, 2022 I also had trouble starting with fuel drain back after a couple of weeks, so I fitted a holley electric flow through fuel pump near the tank and a switch under the dash. Once the fuel line and carb bowl are full my car starts after a few cranks. It also a back up if your mechanical pump should fail. 2 Mach1 Driver and bigmal reacted to this Quote Share this post Link to post Share on other sites
Mach1 Driver 538 Report post Posted September 30, 2022 I've always had a leak somewhere in the carb casting making the garage smell and the bowl dry up in a few days. Even on the bench I could never find it. But I didn't think of adding an electric pump to refill the bowl guickly at startup- that's ingenious! I wish I'd thought of that 50 years ago. Of course I could of just replaced the carb. Quote Share this post Link to post Share on other sites
det0326 174 Report post Posted September 30, 2022 3 hours ago, Mach1 Driver said: I've always had a leak somewhere in the carb casting making the garage smell and the bowl dry up in a few days. Even on the bench I could never find it. But I didn't think of adding an electric pump to refill the bowl guickly at startup- that's ingenious! I wish I'd thought of that 50 years ago. Of course I could of just replaced the carb. Terry, U could also get a boat motor gas tank bulb to pump it up. LOL 1 Mach1 Driver reacted to this Quote Share this post Link to post Share on other sites