BG Carb Tech Tip
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Joined: Aug 1999
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From: At my Bar drinking and wrenching in Lafayette Colorado
BG Carb Tech Tip
For those of you running BG carbs, I just wanted to give you a heads-up caution when you do your rebuilds or replace the gaskets….
I’ve had 2 Forum members send me their BG carbs after they refused to idle following a rebuild. The problem in both cases was with the throttle plate gasket (the gasket between the throttle plate and the throttle body). If you use Holley gaskets when you rebuild your BG (the normal thing to do), the Holley throttle plate gasket will block off the fuel flow for the main idle metering circuit between the throttle body and the throttle plate. This means you get no idle fuel discharge, so the carb will only stay running if you keep pumping the gas pedal. The carb will run okay at cruise and WOT, but it will die as soon as it returns to idle.
To solve this, you must either use a correct BG gasket, or you must slot the idle fuel transfer holes in the Holley gasket using an X-Acto knife. The holes in question are the outer fuel transfer holes at all 4 corners of the BG throttle plate. If you lay a Holley gasket on top of the throttle plate, you will see that the outer 4 holes will be blocked off. To fix this, simply slot the holes in the gasket to expose the holes in the throttle plate. The slots in the gasket will line up with the mating slot in the throttle body, and the carb will work great.
One of our Forum members had contacted the Tech Line at BG regarding this problem, and they were unable to troubleshoot it or assist with the issue. If you have problems like this, feel free to contact me – I’ll do what I can to assist in any way.
I’ve had 2 Forum members send me their BG carbs after they refused to idle following a rebuild. The problem in both cases was with the throttle plate gasket (the gasket between the throttle plate and the throttle body). If you use Holley gaskets when you rebuild your BG (the normal thing to do), the Holley throttle plate gasket will block off the fuel flow for the main idle metering circuit between the throttle body and the throttle plate. This means you get no idle fuel discharge, so the carb will only stay running if you keep pumping the gas pedal. The carb will run okay at cruise and WOT, but it will die as soon as it returns to idle.
To solve this, you must either use a correct BG gasket, or you must slot the idle fuel transfer holes in the Holley gasket using an X-Acto knife. The holes in question are the outer fuel transfer holes at all 4 corners of the BG throttle plate. If you lay a Holley gasket on top of the throttle plate, you will see that the outer 4 holes will be blocked off. To fix this, simply slot the holes in the gasket to expose the holes in the throttle plate. The slots in the gasket will line up with the mating slot in the throttle body, and the carb will work great.
One of our Forum members had contacted the Tech Line at BG regarding this problem, and they were unable to troubleshoot it or assist with the issue. If you have problems like this, feel free to contact me – I’ll do what I can to assist in any way.
