Zenith rebuilds

[dcraigmyle]

Does anyone know of a carburettor rebuild service in the UK.
Sent them to USA last time but the weak pound is making this look expensive.
They are zenith 32 NDIXs
David

[neilbardsley]

Chris on here as fetuhoe?

You might be interested in reading mycar adventure as I think you can DIY.

Charles from the 356 registry produced a good guide but unfortunately has pasted away so I don't think they are available.

However, if you do have go to the US Bruce Smith at http://www.sparkingplugs.com I agreed the £ isn't on our side but it's more the postage and custom. However, you will not be disappointed with Bruce's work

[Ashley James]

They're an easy rebuild with a repair kit and manual unless the butterfly spindles are worn and even then doable unless th body needs bushing.

[40 scout]

Agreed

I did mine , out off for ages then went for it, pretty easy, you tube had few good videos too

Steve

[mycar]

Tell us about your carburetors David. What sort of a state are they in ?

[dcraigmyle]

Generally ok
I will post some picks tomorrow.
David

[roy mawbey]

David,

Some wise words above. If you had those overhauled in the States by a company that had a good name they should still be running fine. I presume you have not done a large mileage since?

I have over 130,000 on mine and the throttle shafts show no sign of wear, the idle is fine and stable.

Ron at the registry did write a nice article on the 32 NDIX carbs and I have copy I could mail you if you need it.

I have found the carb's really quite easy to work on providing its not a complete strip down with every item removed. If you have a rebuild kit with all the gaskets, including the manifold ones and new brass mixture screws and providing the accelerator pumps with their small pistons work well as do the needle float valves then its quite possible with correct tuning they will work well.

Sometimes its not the carbs but the ignition system that makes you think its carbs. Some simple checks can be made first of all then have a go if necessary. Do you have a syncronizer to balance the carbs? To check the injection quantities its possible to buy small items to catch and measure the fuel delivered. The float height again is checkable with gauge.

What are the actual problems ? are they poor on idle setting, out of balance, spluttering and no power? I presume you checked all the jets main and idle and the air jets as well as the delivery jets to the injection tubes you can see when you look down the venturi?

Roy

[dcraigmyle]

Hi Roy
These carbs have never had a full overhaul. This is a spare 59 super engine i am running in. I built it with the late Barry Curtis.
I have checked dwell and it is in correct range. the distributor has been professionally rebuilt. Running 30 degrees at 3000 RPM.
Air flow is equal at 900 and 1500 rpm. However the idle is erratic.
I have checked the jets as much as i can with carbs in situ.
I tuned them in accordance with the registry article.
I just do not know how much is due to wear in butterflies hence the question about a UK based rebuild.
On my 57 engine i had the carbs rebuilt by carburettor rescue in the states and they have been faultless.
David

[BD55]

I believe I have a similar problem, (erratic tick over when engine is hot) have rebuilt my carbs recently and am happy with how it went. However I still have play in throttle shafts and have been told that there should be 0.05 max clearance between shaft and throttle body. I believe I have more but have not measured it. I have new butterflies to install so I was going to try this to see if it improves matters.
When you had your carbs done in the States did they do the throttle bodies? Be nice to know what process was used....I guess you could swap throttle bodies and carbs to eliminate fault??

[dcraigmyle]

David, our basic restoration price for a set of 32NDIX carbs is $895 for the pair, plus if there are any parts that need repair or replacement beyond a standard restoration (condition of floats, throttle levers, pump link, threads, shaft, hardware, etc). plus shipping

Our work goes beyond just a rebuild, and is a full restoration service that includes plating of hardware, new butterflies, refinishing throttle levers, gauging all jets along with engine set up/testing. The latter will still leave a certain amount of work to be done on your end as our fuels have different formulations, but they should be close.

Right now, we are quoting approximately 4 weeks from receipt of carburetors

Thanks and regards
Candace Delaney
928.204.0507
www.356carburetorrescue.com

[roy mawbey]

David,

You seem to have made all the correct checks already. I was confused, I thought the carbs that are playing up were the ones you sent to the States.

Sure excess play in the shaft will cause problems and maybe this super engine has done many more miles than normal. With all the linkages off and the butterflies in the upright position I would think you could feel 0.05 mm play.

I just wonder though if its something else. When the engine is off can you twist each ball ended throttle rod on the carb easily with no sticking at all? So you know the carb is fully on its stop.

The idle jets have air and air correction jets as well as the jet itself. You really need the carb on the bench though to check.

I do think the super engines are a little harder to get perfect than normal versions. Maybe that's me but I find that sometimes my super that is set to idle at 900rpm will occasionally drop to 700 or raise to around 1000rpm. Its not often though and never cuts the engine. I do think if it were the normal 60hp engine the idle could be around 600rpm and be stable, the super needs a few more revs or mine does.

The other thing is the manifold to carb gasket. Have you tried new ones? any leak of air will upset the idle. And finally the brass mixture screws are these perfect on the coned end and are they not bent. The air/ fuel mixture delivery could be upset if they are. And I presume you have done the syncrometer test when setting them up.

I have heard they do a great job rebuilding them in the states but for me I would struggle on trying myself to perfect it all rather than pay that amount. Even the re-bushing is not rocket science if in the end the item needs it.

Roy

[jb]

If it only misbehaves when hot maybe check the tappets are not too tight

[Ashley James]

I was advised that erratic tickover might be sticking ATD weights in distributor.

[roy mawbey]

Ashley, yes the weights sticking can cause all sorts of problems. David should take the cap off the distributor and holding the rotor turn it to the stop and let it go.On release it should fly back to the stop cleanly. No hesitation as it nears the return stop. I reckon David has done all that though as he advised the timing checks he made and the advance results in his previous mails.

I do lubricate the felt in the top of the distributor shaft to get the bottom internals oiled though as those springs and pivot points must wear and become weaker or, just dirty I guess over 50 years or so.

Roy

[dcraigmyle]

Distributor is a brand new renuild. Woks fine.
I took the car for a spin yesterday and the right carb is the issue. It is spitting fuel and something is well amis. I have several spare carbs so will try another while i continue to fault find.
David