Zenith Carb question....

[oscar]

When the choke is activated a small rod links from the choke mechanism to the throttle plate and is supposed to open this somewhat to up the idle rpm's.... This does not appear to be happening. The rod moves, but the throttle plate does not. Any suggestions?

Also, the little orange light on the dash stays on...... Not sure why, or even why it's there and what it's connected to.... if anything other than power.

It appears the motor is a 1968/69 and that the lump was shoved into the beast complete with accessories. Also, it appears the dash is not 1962.... in fact there appears to be a lot on the truck that is not 1962, other than maybe the bulkhead....

[Tom109]

Oscar,

Provided that rod is attached at both ends, you can gently bend it to achieve the desired function. For example, I rarely need to apply choke, but a slight increase to the rev's is nice on cold mornings. But if it's very cold, I still need both. So a slight bend to the rod now raises rev's (only) at the initial choke pull, but further travel will also apply choke. Caution as a little bending goes a long way!

I think the 'orange' light is the 'yellow' choke indicator light. There is a switch in the head that whould illuminate this light when the engine reached temperature, signalling you should push the choke back in. Mine has never worked, so I'm going to use this light for a different indication...

Tom P.

[oscar]

OK, thanks. However...... the rod does not move the throttle....at all.

The yellow light used to go out when the engine warmed and I pushed the choke in. I do not know where it's sensor is.....yet.

[LC Rover]

Oscar:
Sounds like the little connecting arm at the base of the carb to which the rod connects, is enlarged and rotating on the spindle. Look at this web site, should give you the answer. http://www.roversnorth.com/web/downloads/instructions/zenith/zenith-carburetter.pdf.

[oscar]

I have that article, thanks.

Well, after some probing and wiggling it turns out that it is all more primitive than I thought. The lever indeed rotates freely and it is supposed to. It has a point sticking out, for lack of a better term, which catches the throttle linkage on the outside and moves it. It was not rotating far enough to do it's job.

So, I removed the rod and shortened it by increasing the bend on the top 90. This did the trick.

Full choke, cranked and started beautifully without touching the accelerator. After about ten seconds it started running rich, and I pushed the choke in a little. Ran perfectly at higher rpm for about 4 or 5 minutes then I pushed the choke in and it ran nice at "tickover".

Now I'm putting the front drive train back together.