Weber vs Solex v Zenith

[Larry S]

I had a rubbish Chinese one for a short while. It was only to be a stop gap but that gap was about 10 minutes as no matter where the air bleed screw was the engine ran really rich. I goty money back but not the £20 in carriage charges.
My current carburettor was rebuilt about 13 years ago and once set up has never needed adjustments to the air bleed screw.

How did you get yours set up?  I can get mine set up,but after several drives it starts running rich and doesn't like to idle as good as it should.

[Alan Drover]

Mine is a BFS rebuilt one. I set it up  about 13 years ago so not too sure how but as far as I can remember I very carefully screwed the air bleed screw fully clockwise then backed it off about 2 turns. Started the engine and made adjustments until it ran and ticked over smoothly after which I set the timing by ear. No adjustments have been needed since.
It's possible on yours Larry that the castings could be warped or the air bleed screw is moving. Is it held by a spring or locknut?
BFS is Burlen Fuel Systems in Salisbury, England. Unfortunately they no longer remanufacture Zeniths , only supply spares.
BFS  is Burlen Fuel Systems in Salisbury

[Exile]

A Rover friend over on Instagram sent me the following pic the other day. Pic was taken in the warehouse of a major Rover parts dealer here in the States.  These are all new Zenith carbs from Asia.  They were so bad customers returned them. He said there are more bins of them. The pic was taken before they were tossed into the scrap metal recycling bin.

I did suggest to the OP that he should try to find an original Zenith and, if needed, get it rebuilt by a reputable Firm.

Aftermarket carbs used to be awful and not worth fitting. I don't know if there a good new Zeniths around these days?

[Larry S]

A Rover friend over on Instagram sent me the following pic the other day. Pic was taken in the warehouse of a major Rover parts dealer here in the States.  These are all new Zenith carbs from Asia.  They were so bad customers returned them. He said there are more bins of them. The pic was taken before they were tossed into the scrap metal recycling bin.

I did suggest to the OP that he should try to find an original Zenith and, if needed, get it rebuilt by a reputable Firm.

Aftermarket carbs used to be awful and not worth fitting. I don't know if there a good new Zeniths around these days?

I have heard of any either.  I know of a gent who found an NOS Zenith.  He installed it and and said the difference between that one and his old one was like that between night and day.

[Larry S]

Mine is a BFS rebuilt one. I set it up  about 13 years ago so not too sure how but as far as I can remember I very carefully screwed the air bleed screw fully clockwise then backed it off about 2 turns. Started the engine and made adjustments until it ran and ticked over smoothly after which I set the timing by ear. No adjustments have been needed since.
It's possible on yours Larry that the castings could be warped or the air bleed screw is moving. Is it held by a spring or locknut?
BFS is Burlen Fuel Systems in Salisbury, England. Unfortunately they no longer remanufacture Zeniths , only supply spares.
BFS  is Burlen Fuel Systems in Salisbury

Sounds like the same method we used on mine. We did use a dwell meter and timing light to help.

Each time we get everything set up just right it runs great and then starts going down hill after several drives.

The volume screw has a spring and the throttle screw has a nut.

[Billy]

I still have the original Solex carb on my 1965 MOD. rebuilt about 15 years ago. Daily driver with Steve Parks? electric fuel pump. I tow a 750 kg trailer a lot and have not had any problems with the recent temperature. Some of the plastic insert fuel filters (inside a glass housing) degrade with E10 fuel and block fuel flow.

Cheers, Bill   

[Alan Drover]

Exile, the only decent Zeniths available now are rebuilt ones.
Larry, it's possible that the castings are warped if all's ok with the air bleed screw.

[TimV]

As I previously said, NOS Zenith parts available from https://seriesparts.co.uk/?page=%2F you can rebuild yourself.

[Alan Drover]

BFS sell repair kits too.

[diffwhine]

I'd caution a little bit about assuming that NOS is the Holy Grail. Those kits contain various bits which can deteriorate over time even if just stored. Its the same reason why I tend to grit my teeth when I read about people enthusing about fitting NOS rear main seal kits. Any parts manager worth his salt will recognise that certain things have a shelf life and there is an inherent risk in fitting items which have sat around for long periods. Nobody knows how well they have been stored or how they have been handled. Comeback on the supplier is difficult. At least buying from somebody like BFS, you can be sure that they will sell you the best available quality and hopefully stuff which won't disintegrate at the first sniff of any E numbered petrol.

[TimV]

These are NOS body parts - which I don't believe are available from BFS. With a second hand proper Zenith (but worn spindle), it can be rebuilt quite cheaply.

[geoff]

Rebuilt my 2 Litre carb maybe 4 / 5 yrs back

NOS gaskets are undeniably superior to modern stuff from any supplier !

NOS rubber goods ( carb ) such as seals and diaphragms are to be avoided at all costs !

My rebuilt carb was supplied with supposedly E compliant diaphragms which have since rotted out - did the supplier tell me porkies who knows ?

Edit : the NOS fibre sealing rings are also way better than new, I've found the new stuff can be incorrectly sized ( metric ? ) and also so hard they won't compress to make a seal. Temptation of course is to tighten even more .... Don't do that !!

Anyway be careful what you buy

[Larry S]

Exile, the only decent Zeniths available now are rebuilt ones.
Larry, it's possible that the castings are warped if all's ok with the air bleed screw.

I did the whole heat and sand process incase of warpage.

[Alan Drover]

I can't think of anything else that would cause that problem unless the air bleed screw pointed end is damaged.

[diffwhine]

O ring quality? Breaking down due to ethanol content? That could create the same effect.