Really baffled by carb issue please help

Hi again
Sorry to post about my carb again but I really have come unstuck and wondering if anyone out there can shed any light please. Feel like a right idiot.

Firstly My carb number is 212844 9706
I bought the correct carb rebuild kit from agricultural & industrial products which stated that it was right for the 9705 and 9706 model.

Rebuild pack came with a fuel valve needle and spring, but on dismantling there was no fuel valve needle spring just a smooth fuel valve needle with no spring grove.

The carb has been cleaned up and reassembled great but the new fuel valve needle and spring seem to stick out to much and don’t allow the float to sit perpendicular and well and there hardly seems like any movement at all.

The new fuel valve seat is bigger than the old one so I can’t use the old fuel valve needle.

Hope this makes sense. Please help.

Thanks

Dan

Oh
I haven’t got a rubber seat
I don’t know what on earth to do. How much up and down movement should there be of the float at the moment it’s about 2mm. This is turning into a nightmare

I'd contact the supplier, as I've gotten the wrong parts from suppliers before. There was a topic on here earlier about a coil for a tractor that in no way was for the tractors listed. It does not sound like it is the right part the way you describe it.

go to mike's carburetor parts put in under search 212844 it will show the parts you should have

Gary Burnett wrote: 2011dandd wrote: It basically seems to be slightly longer than the original which causes it to protrude from the valve needle seat more than it should which makes the float sit at an angle limiting its travel/movement. How can I upload photos to help with explaining the issue? Simple enough to make it shorter.

What do you think? Just file the head down a bit that the float rests on until it’s right?

I worked on getting the seat nice and tight for quite some time. I t got very tight and appears to be tight on the gasket. Maybe I’ll have a go at seeing if I can get another turn from it but I’m not sure I will.

There is no rubber tip on the needle.

The 9705, 9706, 9707, & 9707C Zeniths use all the same Carburetor rebuilding kits. Is it possible the kit was packaged with the wrong needle/seat assy? Possibly. But, in general, the Zeniths usually don't have much float movement to start off with. Mainly, as long as the pontoons sit relatively straight, you should be okay. Some kits come with a needle valve that has a Viton tip, some don't. Just depends on the mfr. of the kit. One thing you do not want to do is crank that seat in. They're only brass, and that seat should install with your fingers. If it doesn't, there's a bur in the theads of the Carb lid and you need to either run an 1/8" NTP tap in it, or run a bore brush in it to remove the bur.  Its easy to strip the threads. Jim in ME made a good point about the seat bottoming out on the gasket, but as I said, the seat should install with your fingers till it seats. Another spot you want to make sure that's it's clean is the fuel inlet. Dirt, rust and debris get trapped in the threads and at the back of that passage way. Run a bore brush in that inlet and get it shiny clean in there. The debris in that passage way causes a lot of needle/seat issues. The Viton needles work good making a good seal when closed, but debris sticks like a magnet to the tips causing overfueling problems, high float levels etc. When I rebuild our customer's Carburetor's, there's a process I go through with every Carb to make sure they are spotless internally so they work and adjust correctly. Make sure the fuel tank and fuel delivery system is super clean also. Avoid rubber fuel lines when you can. Todays gasoline that is equipped with Ethanol  plays havoc with rubber products. Tiny pieces of hose that loosens from the Ethanol head down and get caught in the needle valve. Not sure if you have Ethanol in the uk.  HTH

 

I didn't mention that we sell rebuilding kits for the Zeniths and Marvel Schebler Carbs if interested. Drop me an e-mail or give a call.

HEY! It's NOT "this bloody forum is great," it's "This forum is bloody great" - there's a difference!!!

Yeah and Fanny’s me aunt.

One of my other vehicles is an old London black cab. Marvellous bit of kit. I can highly recommend, really enjoy driving the Bin Lids around in that! Ha ha.

Any particular settings as a starting point for refitting the carb?