View Single Post
Old 07-20-2014, 11:00 PM   #22
markeb01
Senior Enthusiast
 
markeb01's Avatar
 
Join Date: Feb 2007
Location: Spokane Valley, WA
Posts: 8,356
Re: Edelbrock carb hard starting

For what it’s worth, I’ve run Carter AFB’s or Edelbrock AFB’s with a mechanical pump most of my adult life. I loved mechanical pumps because they lasted for decades and I never had one fail. My experience was electric pumps was terrible, left stranded several times, so I had little use for them. That all changed within the last few years.

A couple of years ago I had so trouble much starting my engine I added an electric pump just to prime the system, turned if off and let the mechanical pump take over. As a safety precaution I replaced my perfectly functioning mechanical fuel pump with 4 new ones, the first one was the type that could clock the position (if was defective and the pump lever pieces fell out of the housing). It was replaced with 3 more sealed models (different brands from different stores), and every one of them put out over 10 psi, completely flooding the carb.

I installed a standard Holley 12-803 regulator set at 4.5 psi. which helped with the flooding, but I soon developed a surging problem where the engine would flat run out of gas for no apparent reason. A quick jolt on the booster switch brought the engine back to life before we had a chance to coast to the side of the road.

The bottom line, I have absolutely no confidence in mechanical pumps any longer. I got rid of it and rewired the electric pump to provide constant fuel. Figuring my previous failures were probably my fault, this time I powered the pump through a relay and dedicated ground, mounted the pump at the bottom of the front of the tank, ran a racing pre-filter between the tank and the pump, and left the factory GMC canister filter under the passenger seat.

Once I figured out what the new engine wanted to start, I’ve never had any issues at all. I set all the controls where they want to be, hit the key and it fires up. I don’t know what is different between mechanical fuel pumps from 40 years ago, but I done with them unless something else changing.

Just a heads up for anyone considering the purchase of a new mechanical fuel pump. Ask yourself which technology all of the new cars have.
__________________
My Build Thread: http://67-72chevytrucks.com/vboard/s...d.php?t=444502
markeb01 is offline   Reply With Quote