small backfrires at muffler and carbs..?

[bluehawaii]

Just put my motor back in after replacing clutch but know it backfires ( little popping) from carbs and muffler at idle and deacceleration.....it is intermittent. I did take the carbs( webers) off and put them back on when I took the motor off....linkage seems good. Also new wires ,,,plugs, cap , points , rotor, condensor, it is an 009 distributor, Any help would be appreciated....hate to take it to the mechanic at 100 per hour.

[Jaems]

Most likely you have a air leak from the carbs or muffler. They have to have very flat smooth surfaces and only one gasket will work..


The basic things are: If you mess with the distributor (tuneup or what ever) You need to recheck the timing. Before you mess with the carbs. You need to adjust the valves. For the carbs to adjust correctly the valves have to be adjusted correctly.

If you are going to work on the car yourself. Then you need to get the Orange book and a drivers owners manual. You might also want to join the 912bbs( it is free). That is where you will find most of the 912 Mechanics.

[RichardM912]

Suggest that you look at the earlier thread re popping backfire.

[bluehawaii]

yep..it turns out it was a small air leak from the carbs ...I sprayed brake cleaner and it changed the idle....but after running it awhile it seems to have gotten better...will adjust valves soon.

[Scott Douglas]

All tune ups should start with a valve adjustment. Everything else will change based on this.

[bluehawaii]

I just got some new feeler gauges,,,getting ready to adjust the valves ...wish me luck.