Carburetor Serial Numbers
Tips on identification of various carburetors. Carburetor Identification Service. Representing the next sequential number of carburetor sold to the. How to Identify What CDK Keihin Carb I Have. Distributors keep track of serial numbers and will be able to identify your particular carburetor. Other identification numbers: A very few 4G Series carburetors in 1957 only were stamped with the last 4 digits of the identification number on top of the air horn. Very early B series have the last 2 digits of the identification number stamped on the airhorn.
The most common cause of a stumble is not having an adequate accelerator pump shot. The first thing to do is to look at the discharge nozzle and make sure you are getting a good strong pump shot. If not then you need to inspect the pump diaphragm for a hole or tear.
You will also need to make sure that the pump passage is clear from any trash or debris. First you will need to check the adjustment on the pump. To do this you will open the throttle all the way (WOT). Push the pump arm lever down and then adjust the pump override spring to obtain.015' clearance between the pump arm and lever. If you are having a stumble and no black smoke out the tailpipe then you will need to increase the shooter size.
If it stumbles and you are getting black smoke from the tailpipe then it will be necessary to decrease the shooter size. Setting the fuel level should be the first thing you do before attempting to make any further adjustments.The float level should put the fuel level just below the bottom of sight plug hole. You will make the adjustment with the vehicle on a level surface and the engine idling. You will first remove the sight plug, then to make your adjustment you will need to loosen the lock screw on the needle and seat. This will allow you to turn the adjusting nut to raise or lower the float level. Each hex flat on the nut will change the float level approximately 1/32'.
When you have the fuel level just below sight plug hole you will then tighten the lock screw and reinstall the sight hole plug. Make sure you have a shop towel handy in case you have any fuel leaks from the Sight plug or needle and seat adjusting nut.
The secondaries will not open by free revving the engine. Getopenfilename Default File Path Access more. The engine needs to be under a load before they will open.
If you are still uncertain if they are opening or not you can take a normal paperclip and clip it onto the secondary diaphragm rod. You will then push it up against the bottom of the secondary diaphragm housing, now you will need to go out and drive the vehicle.