Sanity check

[sparkydave]

The other day I checked on the Zenith carb's vacuum pull-off for the quasi-automatic choke, and made sure the piston wasn't gunked up. Well, I took the cover off the end with the 3 screws, thinking for sure there was a spring under there, and there wasn't one. Since Moss's catalog and the service books aren't showing the level of detail I need, is there supposed to be a spring between the piston and the end cap? I thought for sure there was, unless I lost it while I was servicing the carb many moons ago. The good news is I have a spare carb I could steal the spring from, but it's still packed away somewhere after my recent move, otherwise I could look at that one easily.

 

[Morris]

Yep. Definitely a spring in there. The spring should pull the choke cam into full choke. Then the vacuum pulls the piston forward so that it is no longer engaging the cam. Thus the cam is now controlled by the thermospring.

Make sense?

Anyway, when you remove the cover, you see the piston, not the spring. The spring is under the piston in the shaft.

 

[sparkydave]

Ah, thank you sir. I remember seeing a spring in there somewhere, but I couldn't remember which side it was on. Thanks!

 

[DrEntropy]

Sanity check: All systems go!

...just grinnin' over that bi-metal spring and the Rube Goldberg-like engineering. Gotta love the English "simple" answer to an engineering problem! They *imagined* the cars wouldn't sell with a manual choke.

...but if they'd just bit th' bullet and put ~electric~ starters on their bikes, they'd STILL be outselling the Japanese...

Or Harley, at least. /ubbthreads/images/graemlins/devilgrin.gif