Tried everything on backfiring

[mcphatters]

My Club Car runs great if it did not backfire after letting off gas. This only happens after cart is going down the road and then I let off the gas or ease up on the gas. When the cart is is maintenance mode sitting still it will not backfire doing the same things as I was going down the road. Really stumped, I have done everything I know to do which is new carb., adjust valves to spec., replace spark plug, fuel filter, bar-b-q muffler, installed new gaskets everywhere, checked throttle adjustment, checked air filter canister. What am I missing?

[meimk]

When the throttle pedal is released does the carb butterfly close COMPLETELY? Those carbs have an idle set screw: either remove it entirely or back it out till it's about flush & make sure your throttle cable adjustment allows the plate to close when at rest. Almost all the backfire conditions I've come across are from that throttle plate staying open while the engine spins down to a stop. Ignition (spark) grounds out instantly when you release the pedal. The movement of the piston as the engine spins down to a stop is still creating vacuum the same as if it was running. If the carb stays open that vacuum will draw in a burnable fuel/air mix that WON'T get burned - since there is no spark. That mix gets pushed to the exhaust. As soon as you hit the pedal again the new hot gases light the mix pooled up in the exhaust and BOOM.

[mcphatters]

Thank you for your response. Yes the butterfly is closing completely and yes I adjusted the the mixture screw on the old carb and the new carb. It does not matter which direction the carb is adjusted ( too lean or rich or just right ) the same end result happens. Also as stated it does not backfire at all sitting still doing the same thing such as revving and letting off the gas as in running position, it only backfires if driving. Thanks again for the help.

[CP241]

Check ans make sure the cable that runs from the Governor to the carb moves VERY freely with no resistance at all. This cable sticking some can cause this also.

[mcphatters]

It does run freely, thank you for your reply.

[chadwce]

I have a 1996 that backfired and I did everything. If I leaned it way down it stopped backfiring but was hard to start. Finally I disconnect the micro switch that is activated by the accelerator to kill the spark. No more backfire. It may run a tiny bit after stopping but it is barely noticeable. If it was a problem just shift to neutral or turn the key off.

[The Penguin]

did you recently replace the throttle cable on the right side of the cart going into the box?

I had to replace mine last year and was advised by my local shop that if the cart started backfiring - that the cable was just a titch too long and to back it off at the 2-nuts (10mm nuts IIRC) on the passenger side of the control box.

sure enough, my cart started backfiring - just like yours, coming off full throttle.

try backing off the cable - it didn't take much, maybe 1/4 turn.

[PT69]

My did this exact same thing and it turned out the Governor was the slightest of adjustment.. readjusted to factory specs..problem solved

[SpartanDS]

Originally Posted by PT69

My did this exact same thing and it turned out the Governor was the slightest of adjustment.. readjusted to factory specs..problem solved

Where did you find the factory specs?

[lockman1]

#5 and #6...