Zenith 26VME Restoration

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Tight Yorkshireman
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Re: 181 FFC Rolling Resto

Post by Tight Yorkshireman »

Decided to have a go at my spare 26 VME following on from tavistocks suggestions
Just look at the gap in the mating of the float chamber to the main body! That’s unbelievable So need to do several things but first things first.
Gap through distortion
Gap through distortion
26VMECarb150511 006.JPG (50.62 KiB) Viewed 3770 times
Got myself a flat board its PVC but it’s on a flat old kitchen work top in my garage.
My flat board
My flat board
26VMECarb150511 002.JPG (55.64 KiB) Viewed 3770 times
Flatted the float chamber surface. The abrasive used is fine wet & dry
Cleaning float chamber mating face
Cleaning float chamber mating face
26VMECarb150511 001.JPG (76.43 KiB) Viewed 3770 times
Float chamber mating face cleaned
Float chamber mating face cleaned
26VMECarb150511 003.JPG (70.57 KiB) Viewed 3770 times
Then removed pegs from the upper main carb body to allow me to flat that off and more
See next batch coming up.
Removing gasket loacting pegs with pliers
Removing gasket loacting pegs with pliers
26VMECarb150511 009.JPG (69.88 KiB) Viewed 3770 times
Regards

John
John (Tight Yorkshireman)
First referred to as the Tight Yorkshireman in editions of the Clubs Spotlight: Autumn 1996 Page 40 and Autumn 1997 Page 15
Tight Yorkshireman
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Location: Sheffield

Re: 181 FFC Rolling Resto

Post by Tight Yorkshireman »

Any way the gap seen on the previous photos was after I had flatted off the surfaces you can see here to get a true assessment of the distortion to be tackled.

Removed the pegs as previous and now needle valve to allow the surface to be accessible without bits protruding.
Removing float chamber needle valve
Removing float chamber needle valve
26VMECarb150511 010.JPG (72.64 KiB) Viewed 3767 times

Float chamber needle valve removed
Float chamber needle valve removed
26VMECarb150511 011.JPG (72.76 KiB) Viewed 3767 times
Placed main carb body on my flat board and “rubbed” away keeping it flat on the fine wet and dry and flat board.
Flatting off upper float chamber face on main body
Flatting off upper float chamber face on main body
26VMECarb150511 012.JPG (53.62 KiB) Viewed 3767 times
Can see the almost clean flat mating surface and it really shows the deviations when doing this.
Float chamber upper face flatted off almost
Float chamber upper face flatted off almost
26VMECarb150511 018.JPG (52.75 KiB) Viewed 3767 times

More to follow

John G
John (Tight Yorkshireman)
First referred to as the Tight Yorkshireman in editions of the Clubs Spotlight: Autumn 1996 Page 40 and Autumn 1997 Page 15
Tight Yorkshireman
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Re: 181 FFC Rolling Resto

Post by Tight Yorkshireman »

I decided that carefully I would use a small file to remove the excess from the main carb body to reduce the enormous tapered gap. This I did with some care and step by step using the eye to a lighted background. I got to what I regarded near enough as this is a tricky operation and many members will think this is a no go area, but it is a spare and I am fairly confident as I do have a plan “B”
Next bit I made a smaller flat sheet/strip section to fit onto the emulsion block face of the float chamber. (The emulsion block is removed). The small flat strip then has a measured to fit length of emery paper which I clamped onto the flat strip with small “G” clamps which I bought a pack of three from a £1 shop. The pack of three are the “G” clamps by the way! Not the pack of three I used to ask my dad what were they and why did he get them every time we went to the barbers shop all those years ago
Anyway I then clamped the flat strip/emery to the float chamber body with my third clamp and keeping the float chamber faces flat together rubbed away. This was in an effort to straighten op and make a more match-able surface of float chamber to the main body of the carb around the emulsion block
I did this for a while and it is very arduous needing recovery periods. Had to stop due to commitments but will continue and its getting there. Took off the flatting device and it doesn’t look bad. I am reasonably confident at this stage but will reveal more later

Regards John
Attachments
Flatting contraption
Flatting contraption
26VMECarb150511 024.JPG (84.8 KiB) Viewed 3765 times
Flatting contraption
Flatting contraption
26VMECarb150511 023.JPG (88.64 KiB) Viewed 3765 times
Flatting contraption
Flatting contraption
26VMECarb150511 021.JPG (92.15 KiB) Viewed 3765 times
Flatting contraption
Flatting contraption
26VMECarb150511 019.JPG (95.8 KiB) Viewed 3765 times
John (Tight Yorkshireman)
First referred to as the Tight Yorkshireman in editions of the Clubs Spotlight: Autumn 1996 Page 40 and Autumn 1997 Page 15
AustinofEngland
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Zenith 26VME Restoration

Post by AustinofEngland »

Zenith as returned from the so called specialist...
Image
Had a look up close at the carburettor, found that it has suffered the usual body distortion.
Measuring the gap between the bottom of the float body to the main body on the emulsion tube side there is a 13 thou gap!
Image
Measuring the the gap between the body and the float chamber there is a 6 thou gap! This means we can establish that it would have leaked fuel and ran like a three legged dog before going anywhere near the engine.
Image
Picking up some tips from the forums the distortion looked quite minor compared with some I've seen, so I've decided to try and correct it by dressing down the float chamber top face to adjust out the distortion.
Image
Stripped out all the jets etc to a bare casting.
Image
I found highlighting the machined face with a marker pen would give a good guide as where the material was removed.
Image
After some trial and error offering the chamber up to the body and measuring with a feeler gauge the gaps started to close up.
Image
An initial trial with both gaskets fitted looked good but on one side there was still a 1 thou or so gap towards the top edge.
Image
This was a combination of dressing the actual main body which had a high spot at the bottom and
Image
years of undoing/tightening the two float chamber bolts. This had crushed the top edge of the body causing a small ring to foul the bolts, with this filled out it allowed movement closer to the main body and the gap closed up.
Image
It's worth noting that with the amount of material removed from the top side of the float chamber that the emulsion tube gasket does not sit flush and may need to be trimmed down, but in this case it was an advantage because the float chamber top gasket did not but up to the edge of the right angle of the main body. When assembled it formed a perfect overlap with the other gasket...
Image
The final thing I've noticed is that the two main jet access bungs have had fibre washers fitted that are too large. One has been cut down so they fit together, but it looks too close for comfort and just asking to leak fuel. Did they have fibre washers fitted originally or are they aluminium / copper ones?
Image
After fully reassembling the float chamber and bolting it all back together and finally no gaps anymore, patting myself on the back I found this in the cardboard box for storing the carburettor....
Image
:whistle: :whistle: :whistle:
Last edited by AustinofEngland on Thu Jan 18, 2018 12:53 am, edited 1 time in total.
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AustinofEngland
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Re: UOL 1957 A35 Restoration

Post by AustinofEngland »

After a think the penny dropped and I remembered that there was a gasket kit amongst the spares.
Image
It's obviously old stock and one of the aluminium washers has a small amount of corrosion, this cleaned up to a reasonable standard.
Image
Now fitted and looking much better!

Interesting information sheet with the gasket kit that states the carburettor will be worn after 30,000 to 40,000 miles and should be replaced with a complete new carburettor to preserve performance and fuel economy!
Last edited by AustinofEngland on Thu Jan 18, 2018 12:55 am, edited 1 time in total.
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Neil Evans
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Re: Zenith 26VME Restoration

Post by Neil Evans »

One of the many quirks of the Zenith carburettor is its tendency to drain the float chamber when left overnight. Though a lot of people seem to live with this and work around it by using the priming lever, it shouldn't happen and ultimately is a waste of fuel. However, it's a fairly easy fix...

The obvious place to look for leaks is the two blanking plugs through which the jets are accessed. Not so obvious is the bottom screw that retains the emulsion block. Like the access plugs, this screw should also have a seal washer under it, though I've often found they're missing...

Originally these three washers were made of copper, but for many years the replacements have been aluminium, which is fine... I've also seen red fibre washers used, though I've never known these to be that successful, so if you find your Zenith has these I recommend replacement with the aluminium type... Checking for leaks on the blanking plugs is easy... Just feel around them with your fingers after the car has stood for an hour or so and if the area is moist, you have a problem.

The emulsion block screw is slightly harder to check as, If the gasket is sealing correctly... though few do... the fuel will leak into the manifold, so if you're certain you have no leaks from the access plugs the problem is almost certain to be this screw. These days I don't leave this to chance and apply thread sealant around the washer and screw head before tightening... :thumbs:
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simonA30
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Re: Zenith 26VME Restoration

Post by simonA30 »

My A30 has a 26 VME. It has given me nothing but trouble, and is quite possibly the worse piece of engineering known to man. Regarding the gap, couldn't you have just stuck some filler in it ?
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Nelly
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Re: Zenith 26VME Restoration

Post by Nelly »

I love how in one breath you talk about terrible engineering and in the next you suggest just sticking some filler
in it. :rol:

I imagine they were pretty decent engineering of the time... but maybe not by today's standards. (Although, I'm not sure how many modern car parts will still be operational in another half century+)

If you are going to be running an 60 something year old car, you really have to be willing to repair and service a few bits and pieces!

When you own a classic car, you don't get the 'advantages' of a modern car, with their 20,000 mile service intervals and off the shelf replacement items when you need to replace something. And having more advanced engineering in it. You get a different experience, which isn't for everybody.

Out of interest, what is it that attracted you to classic car ownership?

EDIT: Revised my wording!
Felicity and Sam, Owners of 'Nelly', 1955 Black 4-Door A30
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Neil Evans
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Re: Zenith 26VME Restoration

Post by Neil Evans »

Nelly wrote:
I imagine they were pretty decent engineering of the time...
Notwithstanding the fact that the designers never imagined the vehicle would still be around after 60 plus years, machine screws threaded directly into monkey metal on a service item has never been decent engineering... :whistle:
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Nelly
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Re: Zenith 26VME Restoration

Post by Nelly »

Do you think this would have been done to save on cost?
Felicity and Sam, Owners of 'Nelly', 1955 Black 4-Door A30
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Re: Zenith 26VME Restoration

Post by Neil Evans »

Nelly wrote:Do you think this would have been done to save on cost?
I've never been able to establish why Morris used the far superior SU carburettor and since Skinner's Union belonged to the Nuffield Corporation when they merged with Austin, why were they buying from an outside supplier when they had one in the group if it wasn't down to price?... :whistle:
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earthhist
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Re: Zenith 26VME Restoration

Post by earthhist »

Neil Evans wrote:
Nelly wrote:Do you think this would have been done to save on cost?
I've never been able to establish why Morris used the far superior SU carburettor and since Skinner's Union belonged to the Nuffield Corporation when they merged with Austin, why were they buying from an outside supplier when they had one in the group if it wasn't down to price?... :whistle:
1) The SU is not necessarily superior, though it is often seen that way, largely because it is more obvious what you have to do to change the mixture characteristics. Downsides to the SU are 1) that the jets have plastic tubes that fail, and they can leak where it fastened into the bowl 2) need to use oil in the dashpot, which escapes, especially as the SU ages. Fixed jet carbs have the advantages of fewer moving parts. Having said that, the 26VME is unnecessarily weak in having the jets accessed underneath the bowl, something which other Zenith models like the 30VM (which I use) don't have.

2) The A30 was an established product before the MM was given the A-series engine. Doubtless supply contracts were in place for the supply of all the carburation parts. The Zenith worked, was tried and tested. Most of the problems people have with Zeniths are due to dirt, and overtightening the screws that hold the carburettor bowl, and old age. For the intended lifetime, the carb was fully adequate and I have removed perfectly useable Zeniths from scrap cars.

3) At the time, Morris wanted a bit more power for their heavier bodied car. The set up Morris designed would not have been a direct swap into the A30, as the MM manifolds, carb and air cleaner would not fit into the space available. Easy swaps needed to wait for the design developed for the Mini.
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Countryboy
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Re: Zenith 26VME Restoration

Post by Countryboy »

All very interested Gents :thumbs:
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Neil Evans
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Re: Zenith 26VME Restoration

Post by Neil Evans »

earthhist wrote:


3) At the time, Morris wanted a bit more power for their heavier bodied car. The set up Morris designed would not have been a direct swap into the A30, as the MM manifolds, carb and air cleaner would not fit into the space available. Easy swaps needed to wait for the design developed for the Mini.
Though I believe that the Austin - Morris rivalry likely still existed, despite the companies having merged in 1952, it's likely that the production capacity to produce the additional units to put an SU carburettor on every Austin wasn't available...
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Re: Zenith 26VME Restoration

Post by earthhist »

Neil Evans wrote:
earthhist wrote:


3) At the time, Morris wanted a bit more power for their heavier bodied car. The set up Morris designed would not have been a direct swap into the A30, as the MM manifolds, carb and air cleaner would not fit into the space available. Easy swaps needed to wait for the design developed for the Mini.
Though I believe that the Austin - Morris rivalry likely still existed, despite the companies having merged in 1952, it's likely that the production capacity to produce the additional units to put an SU carburettor on every Austin wasn't available...
Yes that is probably true as well.
Richard Johnston, Plymtree Devon, formerly A30/A35 Club Technical Officer and President
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