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R2GTHAWK
04-12-2007, 11:12 AM
What is the correct location for the throttle connector rod
in the pump operating arm for an R2 AFB? Mine was set in the bottom
hole and the manual indicates the center hole, but that was not
for an R2 engine.
When I open the throttle from idle, I sometimes get a little
backfire through the carburetor. I am adjusting my newly rebuilt and restored R2 AFB.
Any suggestions would be appreciated.
Thanks in advance for your help.:):)

Terry Stinehelfer
Bucyrus, OH
http://i150.photobucket.com/albums/s85/R2GTHAWK/100_0267.jpg

Dick Steinkamp
04-12-2007, 11:45 AM
Terry, you have the accelerator pump arm in the leanest position. The pop coming off idle is generally due to the engine going lean. I'd try one of the two richer holes for the pump arm and see what happens.



http://thenobot.org/images/s2d/s2d_01.jpg

JDP
04-12-2007, 11:58 AM
You have it in the correct hole, and if you have a 4 speed, you even have the correct throttle rod. :) ( often it's wrong)

64 Commander-64 Daytona
64 GT R2 clone-63 GT R2
63 Avanti R1
63 Daytona convert-63
63 Lark 2 door
62 Lark 2 door
60 Lark HT-60Hawk
59 3E truck
52 & 53 Starliner
51 Commander

StudeRich
04-12-2007, 03:52 PM
Wait a minute guy's... I am not trying to say you are both wrong here, but looking at that thing I'd say it is in the RICHEST hole now! If I understand this right the throttle rod PULLS to the firewall, causing the accelerator pump rod to lift causing the plunger to go down right? Therefore, you would get the longest stroke on the pump (largest amount of fuel) in the farthest out hole right? If you say I've got my head screwed on backwards, I'll probably agree! [:0]:D

And if R2 engines need to run rich to avoid leaning out and burning a piston that might be where you want it? :)

StudeRich
Studebakers Northwest
Ferndale, WA

41 Frank
04-12-2007, 04:25 PM
I am not a mathematician but I do know that the picture shows the link to be in the leanest position. Think about it, as the trottle moves the arm would move less in relation to the trottle therefore a smaller shot of fuel would result as the acc. pump moves less as where when the link is put in the hole closest to the pump piston the piston moves much quicker. and therefore provides a longer pump stroke.:)

JDP
04-12-2007, 05:02 PM
You do have it backwards, bottom hole gives the shortest stroke and leanest shot, it's a common mistake though.

64 Commander-64 Daytona
64 GT R2 clone-63 GT R2
63 Avanti R1
63 Daytona convert-63
63 Lark 2 door
62 Lark 2 door
60 Lark HT-60Hawk
59 3E truck
52 & 53 Starliner
51 Commander

GTtim
04-12-2007, 05:05 PM
My Hawk likes it to be in the hole closest to the carburetor. (Avoiding the lean/rich discussion all together)

Tim K.
'64 R2 GT Hawk

bige
04-12-2007, 06:04 PM
That sure is pretty...I run my R2 in the center. I don't think there is truly a right or wrong just a right for your particular car. The position of the rod changes the duration of the spurt so saying "lean or rich" is a little mis-leading. The volume of fuel that comes out of the nozzles doesn't change when the pump moves just how long it lasts. What you want to make sure of is that you have a spurt. It should be strong no matter where the rod is positioned. Pop the carb hat off with the car off and move the throttle linkage and look at the stream. It should be strong with very little movement of the throttle rod. A dribble is not good, it should be a strong spurt. If you have a strong stream I would check timing, and on a long shot while you have the hat off check to make sure the metering rods are moving freely.

ErnieR

http://i146.photobucket.com/albums/r241/AvantiR2/avnatiglamour007.jpg

Karl
04-12-2007, 09:16 PM
The center hole is a good starting point.Terry is in the leanest position. Some times the rich position will cause the idle speed to jump up a little. As Dick said popping thru the carb is a sign of being lean.Being this a new installation check for any vacuum leaks.

63 Twin Supercharged Avanti
64 Avanti R3w/NOS
88LSC Avanti 350 Supercharged w/NOS