Rochester 2bbl rebuild Q

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Rapid Robert

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underneath the cluster there is a small metal T/spring/& I believe a check ball on the other end of the spring. the "T" is embedded in a bit to the casting. should I go thru the effort to remove it before I soak it all? thank you for your time. RR
 
underneath the cluster there is a small metal T/spring/& I believe a check ball on the other end of the spring. the "T" is embedded in a bit to the casting. should I go thru the effort to remove it before I soak it all? thank you for your time. RR
Robert, that is the pump discharge spring and check ball. I think I would carefully remove it to assure you get that passage clean. Here is a nice diagram if you don't have one.
http://oldcarmanualproject.com/manuals/Carbs/Rochester/2-Jet/Manual/Part2/MCarbRoch73802GPart202.jpg
 
Save the old check ball. After you get it all cleaned up, drop the old check ball back down in there. Then reach down in there with a small punch and give the top of the ball a little wack with a small hammer. This will assure that your seat is concentric. Turn the carb body upside down. If the ball doesn’t fall out then tap the body on the bench.
 
How stringent is your tech for that class Over there?
 
Over here at Pittsburgh motor speedway, (1/2 mile) when the hobby stock class pulls in for inspection, the officials go get a hot dog. 2 years ago we won the last race of the year by 4 seconds. Last year we set the track record. But if they look down into the carb we’re toast!!
 
I wont ask! 4 seconds is a runaway! there are imca hobby stock specs for booster height & 2 others. I ain't up on that so I didn't pay any attention to them. do you know what your front alignment specs are? I gotta hit the hay as it is about midnight. I will check back tomorrow (its 11:48 PM)
 
Not my car. It belongs to a customer who fields 3 cars in that class.
 
at Potomac in Md. they are tight ,every night top five have 5 things checked on the cars and carbs is always on the list
 
allowed are machining: the booster to maximum .250" ID with a minimum height of .625" and a maximum 1.375" venturi ID and a maximum 1.6875" throttle bore ID all of which are above me but I recollected something about using 2 gaskets under the cluster to raise it up a bit I would think for more airflow thru the venturis.
 
It puts the bottom of the boosters in the fastest part of the Venturi.
 
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