Zenith Carbs

Hello, I have a 67 230 with dual Zenith carbs. I can not find any documentation on how to adjust them. My car is running rich (I think, from the smell) and it hesitates when accelerating from an idle. It also backfires when slowing down with the engine. I have the idle at 730 RPM and 1º BTDC. Any help would be most appreciated so I can get back on the road.

Thanks
Joel
67 230

[mbdoc]

Normally carbs don't have to be adjusted, only when there's a problem with something else. Make sure that the chokes are opening completely. Also the float level is critical, failure of needle & seat is common. Either of these will cause rich running.

Boy, does that sound familiar! I've been working on my twin Zeniths in my '71 250 for about 2 weeks now, and I had a similar problem as you (acceleration hesitation, stalling, etc.), but also had backfiring through the carbs. I did a complete rebuild from a kit of both and checked the flatness of the throttle body/float housing joint (which were slightly warped). I'm just now getting the hang of tuning them, but I too am concerned about incorrect float level. My Haynes manual gives only a vague description of how to measure the float, so if you get some information on the exact measurement procedure, please pass it along. Otherwise, good luck - they're a love/hate relationship waiting to happen. As a friend told me once, carburetor is French for "don't mess with it"!