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View Full Version : Pullover....maybe.



Doug_Guilds
04-30-2011, 06:32 PM
Ok I had a huge pull over problem. (2300 Ford with a 350 Holley) Car idling, rev it up and it pulls over at about 4-5k. So I put in a anti pull over diaphragm, adjust the pump lever and don't get the pull over when revving the car. But at a test session today it still feels like it is pulling over under load. Free revving no pull over, on track pull over, or something similar.

Now my question is, can the pull over problem show up under load only, or should I be looking for another problem?

Racedad
04-30-2011, 10:28 PM
Maybe your jets are too small.If it was jetted for best performance before now maybe too lean without the pullover?

longhornracer
05-02-2011, 10:56 AM
I have ran that diaphram without any issue at all.. Im not saying yours isnt the issue but from past experience I would start looking at other things

Doug_Guilds
05-02-2011, 05:16 PM
I have ran that diaphram without any issue at all.. Im not saying yours isnt the issue but from past experience I would start looking at other things

The more I thought about it the past couple days, I am leaning the same way. Other things. I am wondering if maybe a vacuum leak or my float level could be to low. Something along that line.

longhornracer
05-03-2011, 03:55 AM
yeah almost sounds like running out of fuel or ign problem. I had one that would only stumble like crazy at high rpm under a load and i changed the coil and fixed my problem after a million other things! I hate those little gremlins!

Mod75Racer
05-26-2011, 06:47 AM
We had a similiar problem when our class went to a stock 350 Holley type carb. The wise carb guys finally came up with a small ball bearing and a spring installed beneath the squirter. It cured our pull over problem without using a anti-pullover squirter. We were running 2.3, 2.5 fords and 2.5 chevys.
Hope it helps, check it out with your carb guy.

Headhunter
05-26-2011, 08:54 AM
They will tell you that works but I promise you it does not. By the time you get enough spring pressure the pump circut will not operate. To overcome th epressure of the fuel and the vibration trying to lift the check off the seat.
I tried at least 100 different things and itterations of those things before the diaphragm cure came. I used a vibration table to test the concepts witn no vacuum through the carberator and tried everything from holes to ball checks even used heavy metals to make different weight and shape checks. The only thing that worked was the diaphragm that Joe sells.
To answer your question, chances are once it is installed it should stop pullover under all conditions except at idle and small partial throttle opening.

84Dave
05-26-2011, 10:59 AM
Doug...... we found, on both the 350/500 2-bbls, the best float level, with the engine warm immediately off the track & in the pits, was 1/16" BELOW the bottom of the sight-plug threads in the bowl. Also, if the 350 has been around awhile, change the o-ring on the needle/seat assembly in the bowl. If that o-ring is deformed or has 'hardened' even a slight amount, fuel-pump pressure can force fuel by the o-ring, with the needle/seat closed, and flood the float bowl. Then you'll danged sure have pullover on the track. -Dave-

Doug_Guilds
05-26-2011, 08:47 PM
Thanks for the ideas guys, I did change the coil, and changed a spacer plate that had a small vacuum leak with no change. Now I did pull the plate and check the jets, and they were 72's. From what I have read 60-65 seems to be about what people run, so I went down to 62's and changed the plugs which looked to rich. I won't get to test again till next week so Hopefully this will fix the issue.