Thank you Rick, I think I did it correctly.
Zenith Help
- Thread starter HB Chris
- Start date
This was the rear carb, pretty wet when I removed the second stack. Got everything cleaned and reassembled, even the tiny screw underneath, can’t get the butterfly valve within 1.5mm of the lever but not bad. Poured a bit of gas down the vent pipes, car fired right up, 1400 rpm, can’t get it to drop down so maybe I will loosen those two screws a bit and rotate choke housing CW. However, gas is dribbling into the venturi of the rear carb which is not good, front carb looks great, gas is atomized. New float needle not closing? Rick, your thoughts?
Honolulu
Well-Known Member
Fast idle is controlled by an arc-shaped bit in the choke housing that has steps in it. The fast idle screw sits on the steps, sets how much the choke plates stay open. The fast idle screw is only accessible through a port in the choke housing. Getting it all right is enough to make you want fuel injection, which you'll never understand, and cast it all to a pro. (At least that's how I've felt about it).
Geez you got a lotta crud (technical term, ya know) in the float bowls. Really need an effective filter, Mr. Chris. I assume you have the filter on the gas line inlet? A lotta stuff can get through that metal mesh, but IDK if it's still coarse enough to obstruct a jet.
Geez you got a lotta crud (technical term, ya know) in the float bowls. Really need an effective filter, Mr. Chris. I assume you have the filter on the gas line inlet? A lotta stuff can get through that metal mesh, but IDK if it's still coarse enough to obstruct a jet.
Charlie, I understand and explained all those steps. Float bowl pic is when I took it apart not after cleaning.
stphers
Well-Known Member
Sounds good to back off the chokes, by leaning ( rotating ) the choke housing out. If I remember right, didn't you sat that you richened up the choke housings That just makes it longer for the chokes to come off. There should not be any spring tension from the chokes once the eng is warmed up try that
Rick, yes I had turned them CCW, idle is a bit lower now but float in rear carb is allowing gas to run into the VenturI.
Cold/fast idle much better but after four attempts gas still runs out of Venturi into the throat after reinstalling old float valves. I removed one Venturi and noticed a tiny O ring where it meets the body. Haven’t reassembled yet.
Hard to believe but gas no longer flowing into the throat after replacing that tiny o-ring where Venturi meets the carb body. It is running!
stphers
Well-Known Member
It is all about sealing the sections properly and making sure the vacuum is getting and going where it is suppose to go Good on you, now, once you have the chokes and fast idle set up, just redial the mixtures and idle speeds in Forget about what the readings coming out the tailpipe and set up the carbs by feel. Now is the time to do zen carbs and become one with the carbs
Chokes and fast idle are pretty decent but could use some fiddling. I am just never going to touch those hard to reach adjustment screws!
stphers
Well-Known Member
Get a piece of welding rod and hammer the end into a flat , then shape it with a grinder. Bend the other end into a V shape so you will have something to twist the newly made adjustment screwdriver, you can bend it any way you want. There is a sweet spot to reach those screws
I’m at 1050 warm without the air cleaner now.
Back to gas leaking into main throat after swapping Venturis. Float needle has three spacers and spring returns so I know that is working.