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ScottT
06-28-2010, 04:21 PM
Okay, I rebuilt the carb over the winter with a kit from another parts supplier, the kit looked pretty gamey, some really tarnished bits, others obviously used but I figured I'd give it a whirl, it was what I had on hand and I didn't feel like fighting with the guy.

The rebuild went well I thought having not done one in about 15 yrs.

The truck, a '68 109, starts, runs briefly then dies. You can't restart it for at least 10-15 minutes after it dies and it leaks gas onto the manifold from the carb (stuck float?)

UPS just dropped off a zenith kit from our hosts.
Do I attempt a rebuild with good parts? The bad kit is making me leery to attempt it, no sure if I screwed up or if it was the kit.
Anything to look for while doing the rebuild?

Thanks
Scott

gudjeon
06-28-2010, 06:48 PM
Upon taking it apart, I always like to see if I can find the fault during disassembly. Remove top cover with float, needle and seat intact. Holding it upside down, check that the float height is correct and blow into the inlet to see if the needle and seat do their job. These Zeniths are very tempermental if the float is the least bit too high. I set mine about 1mm under if you know you pump output is good. It works great over the rough and extreme angle better this way (I have found).

If that doesn'y show anything, See how the o-ring is seated. I install mine with a bit of oil and make sure it slips on without twisting or rolling over the housing it is installed on. I even use a very small flat blade screwdriver run back and forth underneath it to make sure it is not rolled- sitting naturally. Then, when you assemble the float assembly cover onto the main body of the carb, you need to feel the o-ring contact before the rest of the assembly does. It is not much, just a hair-as they say.

If it were myself, I would put in the new parts of the new, better kit and keep the old ones as a spare. Again, I would use the float cover gasket that is the thinnest to make a good seal for the o-ring - but that's just me.

You have to be methodical with these little guys, take your time, and have good lighting. I have not met a Zenith I could not sort. I have it down to 4 tools and half and hour. :thumb-up:

Leaking into the carb while hot may be a symptom of heat soak issues and fuel pump acting up when hot. This is another story.

Good luck, Jon

ScottT
07-01-2010, 01:09 PM
I did the rebuilt last night.
How do I adjust the floats?
Any suggestions on the mix and throttle screws?
Thanks

printjunky
07-01-2010, 01:15 PM
It takes some in-depth reading, but it's incredibly useful.

The float adjustment is about halfway down, under the adjustments>petrol level headings.

http://www.roversnorth.com/forums/showthread.php?t=3121

printjunky
07-01-2010, 01:27 PM
I think I'm remembering this correctly ... Flip the top half over. The tab on the float will press on the needle. Measure from the edge where the gasket goes (supposed to have the gasket on it, I believe) to the highest point on the float. Should be 1.26-1.29 inches for rubber float (1 and 9/32 would give you 1.28"). Or 1.2 to 1.24 inches for nylon float (1 and 7/32 would give you 1.22") if you're using standard and/or non decimal measuring tools.