Carburetor help

[ithrowgirls]

It's a 69 155horse buick. When I'm just cruising along like 1k rpms, and I gas it, it coughs, sputters and sometimes dies. Jets are spraying fuel into intake maifold, so fuel is plentiful. Is it possibly electrical? Any ideas would help. <br /><br />Thanks

 

[papdetomaso]

Re: Carburetor help

ITG, I have the same year and engine in my 19ft. My problem was the same as yours (engine stalling when increasing the throttle from wakeless, or about 1000 to 1200 rpm) I assume you also have a Rochester 2GC. I corrected my stall by adjusting the mixture screws to the "rich" side or out just a 1/4 turn at a time until the stumble or stall went away...good luck...Pappy

 

[TwoBallScrewBall]

Re: Carburetor help

Sounds like accelerator pump in the carb needs work. Even though the jets are spraying, the accelerator pump sprays a little extra fuel when going from low to high throttle to compensate for the change in vacuum when the throttle is opened abruptly. It is specifically designed to alleviate the hesitation you're seeing. Richening the mixture screws will only mask the problem and eventually foul out your plugs.

 

[LubeDude]

Re: Carburetor help

Still could be an accelerator pump problem.<br /><br />Say Papy, do you still have a Detomaso?

 

[papdetomaso]

Re: Carburetor help

LD, yes I have a 72 Pantera. I've seen you post on the P.I. forum, seems we have a couple of the same interests...Pappy

 

[LubeDude]

Re: Carburetor help

Ive tried to make sure people know that these cars are not my cars, I maintain a collection. I think I am finally getting to the point of the car being able to be driven more than from one shop to the other. I am beginning to really disliking the car. Tracking cooling issues has been my full time job for about a month. Now, with new preasure tank and overflow tank, and the right radiator caps, I think I finally have it holding preasure.

 

[ithrowgirls]

Re: Carburetor help

Hey guys,<br /><br />thanks for the replies. I pulled apart the carb (it is the rochester) and found out the accelerator pump was not drawing fuel into it's reservoir. I got it cleaned out, so fuel draws in like it should. However, it still backfires, though not as bad. It still kills the motor sometimes when it does backfire. It idles smoothly and everything else seems to be going well. I just can't get the blasted thing to work quite correctly.<br /><br />Any other advice would be great. Ideas on how to adjust the pump or what not would be great!<br /><br />Thanks

 

[papdetomaso]

Re: Carburetor help

ITG, I just pulled out my last carb rebuild instructions and the pump rod adjustment read as follows- (1) back out throttle stop screw. hold throttle valves tightly closed. (2) Measure distance from top of air horn to top of pump rod. (3) bend pump rod to adjust. The measurement is 1 5/32 inches. Also the float measurements are 1 29/32nds for the float drop and 19/32nds for the inverted float measurement. Hope this helps...Pappy