Q-jet starting issue

[Mike Hedger]

One last thought, I wonder if the accl. pump check ball is sticking after the car sits? This could happen if the float bowl is dry from the main well plugs leaking also.
Give it a look the next time you have the top off. Hope this gets you going, Mike

[Ben Kallies]

Thank you both Mike and Alan. I appreciate you taking the time to respond. That gives me a few areas to work with. If I find something, I'll let you know. - Ben

[Mike Pearson]

Ben,

All that is happening is your accelerator pump plunger is drying out when your car sits for a while. When you are ready to use your car fill the carb up with gas by brunning the fuel pump a day prior to starting it and this will swell up the plunger and the accelerator pump will work again. The racing gas is very dry especially C-11. When your car is sitting fill the carb regularly to stop the drying out this will solve your problem. I have the same problem on my super stocker. Dont get to race enough.

Mike

[Dean Oliver]

Ben,

You have received very good advice so far. One question, is the rubber pump cup on your accelerator pump black? If it is, these cups usually have a short life when exposed to racing fuels. Like Mike mentioned, C-11 is the toughest to deal with because it even seems to leave a residual film inside the carb when it dries. If you have the black cup, I'd be happy to send you one of mine to see if it helps.

I would also recommend that you take a look at the check ball and the seat that it sits in to make sure they are clean. If the check ball is not sealing properly, the upstroke of the accelerator pump could be sucking this circuit dry. I can give you some pointers on how to check this if you want me to.

Keep in mind also, the bowl area of a Q-jet is very small, so if the car sits for a couple of weeks most/all of the fuel inside the carb can be lost to evaporation. If this is the case, then the carb is simply "empty". However, this leads to the situation described earlier where the pump cup will now start to dry out.

Dean Oliver
www.deanoscarbs.com

[Dean Oliver]

Ben,

You have received very good advice so far. One question, is the rubber pump cup on your accelerator pump black? If it is, these cups usually have a short life when exposed to racing fuels. Like Mike mentioned, C-11 is the toughest to deal with because it even seems to leave a residual film inside the carb when it dries. If you have the black cup, I'd be happy to send you one of mine to see if it helps.

I would also recommend that you take a look at the check ball and the seat that it sits in to make sure they are clean. If the check ball is not sealing properly, the upstroke of the accelerator pump could be sucking this circuit dry. I can give you some pointers on how to check this if you want me to.

Keep in mind also, the bowl area of a Q-jet is very small, so if the car sits for a couple of weeks most/all of the fuel inside the carb can be lost to evaporation. If this is the case, then the carb is simply "empty". However, this leads to the situation described earlier where the pump cup will now start to dry out.

Dean Oliver
www.deanoscarbs.com

[Ben Kallies]

Thank you Mike and Dean,
It sounds like you've both got the problem figured out. I appreciate your input. Dean, I would love to try one of your pump cups. I'll give you a call soon.

Ben Kallies C/S 3869

[Ben Kallies]

Mike Pearson,
Just thought you would be interested to know. I followed your suggestion and ran the fuel pump the day before I started the car, and the carb worked great. Thanks for the tip.
- Ben Kallies C/S 3869

[Mike Pearson]

Hey Ben,

I am happy to help, It sure is helpful to have all of the experiances of other racers to help solve our problems. Luckily yours was a cheap fix.
Best of luck
Mike