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whitehillbilly64
21st July 2015, 05:37 AM
Hi,
Should I get a New after market Zenith carby for my 2 1/4,
or get an original one and put a kit through it.
What should In look for with the old ones ????
Thanks
whitehillbilly64

Ozdunc
21st July 2015, 04:10 PM
From experience, the new carby I got I couldn't get to idle smoothly, so I redid my old one.
The only things I did was replace the gasket in the accelerator piston and reface the two main mating surfaces, replacing with a fresh gasket.
Works fantastically.

Refacing is easy. A wet piece of 1000/600 wet n dry paper on a pane of glass will give a dead flat surface.

crackers
21st July 2015, 08:20 PM
Dunno whitehillbilly64. You're hamstrung a little by not having one now (that's how I read your post).

Here's how I'd go about it.
- price a new carby
- get a feel for the prices of second hand ones
- price a carby rebuild kit
- see what sort of difference there is.

Carby kits are usually just the rubbers but might include jets as well. It's dead simple to rebuild a carby, particularly a basic one like this. What will kill the end result are air leaks - the mounting base as Ozdunc described, the butterfly bushes. All things can be fixed and it's just a matter of what it all adds up to, which is the attraction of a new one, but only if the new ones are good units.

Just some random thoughts mate. Wombat came with a Zenith carby and my first step will be to rebuild that - having to find one messes with that economic/effort balance somewhat.

gromit
22nd July 2015, 06:01 AM
Hi,
Should I get a New after market Zenith carby for my 2 1/4,
or get an original one and put a kit through it.
What should In look for with the old ones ????
Thanks
whitehillbilly64

Putting a kit through the old one may help along with refacing the mating surfaces as already mentioned. Is there a 'carby company' locally that will refurbish the carby for you ? They tend to machine out & fit spindle bushes to reduce the air leaks.
Locally it costs about $250 so maybe compare that to the price of a new Zenith.


Colin

JDNSW
22nd July 2015, 07:11 AM
A new one should be better, although there have been reports of them coming from the factory with the mating surfaces between the top cover and the main body not being flat (but this is likely to be a problem with a second hand one as well - seems to be a design problem). The problem with a second hand one is that the throttle shaft and the bit of the body it turns in are almost certainly worn. This is likely to cause idling problems, and, while fixable, is a fair bit of work, and expensive if you pay someone to do it. Refacing the mating surfaces is easy with a bit of plate glass and a sheet of fine wet and dry.

John

Davehoos
27th July 2015, 02:23 PM
My job last weekend was to replace new carby on Ser3 2 1/4. took the vehicle in for rego today so I needed it to run. $195 + $33 for spare kit.


I been stuffing around with the original since I purchased the vehicle, intermitant black smoke rough idle, running on. misfire-like burnt valve.
Last week it was flooding and the idle jet screwed in hard. bending the float lever did not stop the fuel when carby assembled.


I found the fuel filter as good as blocked it was different to the replacement so it hasn't been refitted.


The cause of the poor mixture was identified as the PCV. I am currenty are using a Nissan valve and its never run so good.

whitehillbilly64
17th August 2015, 06:53 PM
Got hold of a couple of Zenith's
Has any one tried to make a new shaft bush to take up any wear in the butterfly bushes ???? using a stainless steel pop rivet,
Head style 73/ st.s / 10 /10
Drill carby body to take rivet at a push fit with Loctite bearing fit, then drill centre to take shaft ???? nice stainless steel bush.
what clearance between shaft and bush ???? from new.
standard new shaft size ????
Just an idea.
updates to come.


whitehillbilly

whitehillbilly64
30th August 2015, 07:25 PM
Carby kit arrived today.
How much play on the new shaft is to much ????
Should I try and used the old jets ????
Lots of washers, will try and work out where they go !!!!
The 'old' needle valve is rubber tipped. Should I keep It ????
Thanks for your comments

whitehillbilly