holley problem on 429

keane · #1 (**permalink**) 08-21-2003, 03:20 PM

Hi, to all again, just another q!! now that the motor is firing up I'm trying to get it running right prior to taking it out to do the body fit, I have a 750 holley vac sec carb which will be rebuilt shortly, she will start up no problem initially but after 20 seconds or so the motor dies presumeably due to lack of fuel, a few squirts and it will fire again, but I have to fill the primary bowl again, I am going to try a stock pump tomorrow(mech edelbrock fitted) it may be the pumps not operating correctly. anyone dealt with a similar problem? Thanks Dave

Mr.Fixit · #2 (**permalink**) 08-21-2003, 04:05 PM

You aren't getting fuel to the carb's primary bowl. Either your current pump is: not primed, not pumping, has an obstructed inlet, etc.
Or the float bowl has a stuck / clogged needle and seat valve. Either way, you need to get fuel supplied to the carb's float bowl.

keane · #3 (**permalink**) 08-22-2003, 01:33 AM

Thanks mr "fixit", I may not have explained myself 100%, I've put fuel in the bowl physically through the needle valve orifice, and have checked the fuel supply to the inlet, the pump is pumping, wether its enough is another matter,if the bowl has fuel present, everything else permitting, I cannot understand why the motor won't run for a few minutes until the fuel in the bowl is exhausted,I have tried another carb and similar results. Dave

mrmustang · #4 (**permalink**) 08-22-2003, 03:27 AM

Ok,

Let's start with the basics....First off, the 750cfm Holley vac secondary carb is probably not your best choice in fuel managment. Your going to be better off with a 650cfm Holley double pumper to feed your engine. Second, you cannot fill the fuel bowls through the needle valve orifice, as you will most likely damage the idle curcuit in the process. If you think your having a fuel delivery problem, pull the fuel line off the pump, stick it in a bucket or large glass jar, and have a friend crank over the motor, if fuel is coming out in a sufficient volume (you'll know it when you see it), then this is not the problem. Get me the numbers off the side of the choke horn, and let's see which carb you actually have on your hands, you might find that it is not what you think it is, as is a common mistake. Will await your detailed response, and we'll go from there....

Sincerely,

Bill S.

keane · #5 (**permalink**) 08-23-2003, 11:53 AM

Bill, thanks for the input, I'm working all this weekend but will get the info tomorrow(sun) and let you know. Dave

keane · #6 (**permalink**) 08-23-2003, 12:57 PM

Bill, got chance to get in the garage, the carb fitted at present has the number-3310-G with 2088 underneath, I have another holley which is list 4776-3 with 1991 underneath,I did quickly try to check fuel supply and fitted a clear inline filter, it appears that the pump is not filling the filter!!! I cannot believe that both pumps are not working, I am thinking of trying to do a gravity fed system/ or electric pump to get it running, I know I torqued the fuel pump cam bolt and loctited it but am now wondering if it is spinning? Dave

427sharpe · #7 (**permalink**) 11-05-2003, 07:30 PM

Did you plumb the mechanical pump backwards?