I have a second set of Carbs for my 1968 S type 3.4s which I am looking to have rebuilt. I am capable of rebuilding them as I did with the ones I am running on my car at the moment but I was looking to have this spare set professionally rebuilt and cleaned.
Does anyone have anyone they can recommend in the UK for such a job?
I have contacted a couple of companies that are quoting £750 to £1000 for the work and although I know it is a skilled job this just appears to be excessive. These quotes are for what they deem to be a restoration so the carbs come back as new and I am not sure if I want this level or if I just need the carbs rebuilt with an ultrasonic clean and any polishing I can do at home.
Any recommendations would be gratefully received.

Cass I had mine rebuilt by Joe Curto in USA and they are still in the box. $700.00 paid by you-know-who. Plus $46. paid to get them to him.
www.joecurto.com

Thanks Jose but looking for someone in the UK really.

I had a quick look at Burlen, and the parts to do a full rebuild will be about £300 (not counting the the starting carb), so a total price of £700 for a rebuilt set doesn't seem that out of line. Sorry, I can't make a recommendation for a place to have the work done.

Spoken to Burlen. They want over £1000 for the two carbs plus another £400 for the starting carb which they do not rebuild but replace with new.
Ouch!

so what I paid isn't that bad is it? less than half of Burlen's quote.

Burlen is known to be extremely expensive. There must be a specialist in the UK that will do the rebuild competently for considerably less than Burlen.

I am in the process of rebuilding the HD-6 carbs on my Mk2-340. I have the rear one off. The body is soaking in the ultrasonic tank. The jet locking screw is resisting removal. If it doesn't soak loose, Kroil will be next. I cut a KingDick 1/4W combination in half to fit into the available space and ground down both the ring and the shoulders from the open end to get the carb off. There is a replacement on the way that will be used as a breaker because you can only get 1/10 turn full length.
If the chamber and piston assembly are clean and the shaft lightly oiled, how fast should the piston drop when the piston is all the way out and the assembly inverted? I ask because the drop rate in my test horse is several seconds, and the one from my car, a '67Mk2-340, is perhaps just over a second. There is a note in the shop manual about not using metal polish in the chamber and piston... I may have gotten it too clean.
The reason for this exercise is a fuel leak... It turns out there were two sources. First, the fuel feed pipe tee was leaking on the tank side and on the rear carb side. Second, two of the four screws on the bottom of the float chamber on the rear were dripping. The thrust washer was not like a potato chip, but it had somewhat deteriorated. The fuel one is off to the machine shop to be repaired. I am going to rebuild both carbs now that I had to take the rear off.
More to the cost of this exercise, Joe Curto (address above) provided 2 CI-1402 rebuild kits for $120 plus $12.50 shipping. As of now, I have about six hours in removing the air cleaner and the carb, and the first hour in the ultrasonic bath. I don't have a shop rate in my retirement.

I just don't understand where these high rebuild prices come from, the only thing that really wears out on these is the butterfly shaft which requires a new shaft replacement.
The butterfly valve wears to, but it's not rocket science to replace these parts.
I found that the brass shaft wears first on the aluminum and the carb body doesn't need re-bushing, and even if it does where does £750 to £1000 comes in to play to re-bush the carb body.
The aluminum carb body oxidizes on the brass shaft causing the shaft to become "necked" in. Aluminum oxide is very abrasive.

The rest is just simple parts replacement and polishing with no machining involved.

Cass, why would you want to buy new carbs from Burlen, is it because the rebuild kits are out of stock ?
One kit is only £85.88 so £171.76.

What is it with Burlen, the jet assembly is out of stock too, how's anyone supposed to rebuild anything with no parts ?

I think the problem here is the lack of understanding on how these carbs work and how to tune them, with out that knowledge people don't' trust themselves to do it right, and rebuilders take advantage of that.
What pisses me off is when I send something out because I don't have the time to do it myself and it comes back all buggered up and I have to redo it.

Blue, drop test ???
Does it matter, as long as there is no binding, the spring and the oil in the piston controls the rise and fall ?
I find it's very difficult to get the last specs of dirt out, I wash mine in very warm water and dish soap and then blow it dry with compressed air, I then use a clear light synthetic oil for lubrication, like Super Lube.
That usually solves any " rise and fall" problems, outside of damage to the piston or suction chamber.
If they were polished, then that may be embedded in the aluminum and the dish soap with a tooth brush should wash that out.

And 6 hours removing the air cleaner and the carb, how can that be, I think it would take me under an hour to do that for both carbs, if that ?

They are not new Carbs from Burlen just the AED as they don't restore that part just replace it with new.

There are three levels apparently of rebuild.
The first is a clean. No new parts just cleaned and setup.
Second is a rebuild. Cleaned and all new parts and setup. Carbs come back looking old as nothing is vapour blasted.
Lastly there is full restoration which is the £750 to £1000 quoted. This is the following from another company called Coin Engineering..
Labour @ £55 an hour.- Disassemble, ultrasonic clean, vapour blast, reassemble, setup and test twin HD6 carburettors 8 hours.
Labour @ £55 an hour. - Disassemble, ultrasonic clean, vapour blast, reassemble, setup and test Thermo 1 hour.
Parts - Service kits (CSK 37) £120
Semi optional. Replace spindles, re-bush bodies if required (Add £40/carb)
Optional - Zinc Plating with silver chromate (Add £35+VAT)
Add 20% tax on to this and it is over £750

I am waiting for a quote for option 2 the rebuild as I can polish the outside myself and do away with the vapour blast part.

Thanks, JeffR1. I am slow.

At £55 an hour, I would do most of that myself.
For that price I could purchase the reams, I can get a pretty descent finish with a brass wire brush and I have a buffing wheel for the dash-pots.

I guess I'm just living in the past, I prefer to do things myself, I'm more meticulous then most people, I very rarely trust anyone to touch my stuff.

We rebuilt our own with no great difficulty & they are fine. It's hardly rocket science. They are simple but very effective devices. A matter of attention to detail. No false air.

With the transfer holes plugged with something like plasticene (tape often doesn't seal) it should take at least 5 seconds, and ideally about 7 seconds to drop completely. You'dd need the damper in place too, but obviously with no oil in it The ideal is that the piston is a very tight fit and can move under vacuum, so too much clearance means the vacuum can't move the piston in response to engine load.

Agreed. Haynes actually makes an excellent manual for the SU carbs, book number 299.

What would cause it to be outside of those specs ?
The machined tolerances are with in 10,000 thousands of an inch.

And there isn't anything that could be done if it was not with in spec.
I've seen them dropped on a concrete floor and that's it, they're scrap.

I guess what I'm saying is, what is the point of checking this, it's either going to work or not.
They're obviously machined to a very high tolerance at the factory and checked, what is the point of worrying about such a thing ?

The same goes for what kind of oil goes into the damper, long posts have been created over this, it's not even all that critical, and if it gets very cold, use a thinner oil.
God will strike you down if you put anything in there other then the stuff from Burlen.

I've run around with the damper tubes empty because I've neglected to check them, and I've not noticed a drop in performance.

Last night I got the revised estimate which excludes the Vapour blast external cleaning which I think I can do myself with enough patience, wet and dry and some metal polish.
The cost now to

Labour @ £55 - Disassemble, ultrasonic clean, reassemble, setup and test twin HD6 carburettors 4 hours
Labour @ £55 - Disassemble, ultrasonic clean, reassemble, setup and test Thermo 1/2 hour
Parts - Service kits (CSK 37) x2 £120
Total £457 including Tax.

So the vapour blasting appears to be the time consuming part by doubling the labour time and near enough doubling the cost.
I know very little about Vapour cleaning but it seems very expensive.
I could do the whole lot myself by buying the rebuild kits but I would like them properly cleaned Ultrasonically and all the tolerances checked so I might go for this. Expensive but piece of mind that Coin Engineering have rebuilt them properly unless someone comes up with another company that can do it cheaper.

Thanks for that. I was not aware of it.

Rob ~ there is no excuse for high vapour blasting costs either. It's cheap in South Africa.