Zenith 26 VA jet seat

[scrooge]

I have a Zenith26 VA carb off my mk1 Pearl which ive just sonic cleaned but have found a seat from underneath one of the jets in the float bowl has come out.

I can't find a mention of this part anywhere though and i wondered if there should be one of these little top hat seats under each jet in the bowl , so i may have one missing.

 I cant see its purpose though as it would sit underneat the fibre washer that the jet sits upon when in the bowl.    I can't see that the height of the jet in operation would need a reduction in the head of fuel pressure from the bowl by such an insignificant amount that this "top hat" would provide.

Does anyone have and suggestions about its purpose and if i need to find another?.

I only cleaned this carb as when i got my Pearl 15 years ago it was running a little rough and i had another spare i put on that cured the problem .

Ive just bought a sonic bath so thought i'd clean this carb up for future use .

Hopefully ive attached a picture og my jet seat and bowl.

   

[Andy Bennett]

I believe they were under both jets, under the washer. Roger Spearman in the Essex Austin 7 club had a batch made up a few years back. Last I heard he still had a little plastic bag of them. I added a set to my jets on a newly refurbished carb and all was well, although I didn't do a before and after so can't comment on whether or not they acheived anything. Roger isn't on this forum but there are a couple of members who are.
Andy

[scrooge]

I think i may have found a source for this top hat jet seat mow  Thanks

Now my concern is the throttle butterfly plate. One side is slightly worn away at the spindle entry point to the body.
Ive tried Burlen but they dont have new ones.   Im considering silver soldering and then filling back to a close approximation.

I think the damage  to the plate is caused by the poor fit of the spindle due to wear at its bearing surface. I can possibly insert bushes.

Any advice welcome

[Hugh Barnes]

The most important thing about the spindle for the buttery is that ideally, it should be a perfect alignment for the spindle to turn in, otherwise they tend to bind in operation which is not helpful. Alignment of the two holes is something to be done with care..

hth....

[Graham Barker]

Worn spindles and bearings allow air to enter the carburetor throat upsetting the air/fuel ratio. I had a new spindles and Teflon bushes fitted by firm which specialises in rebuilding carburetors.