I have always had problems with the starting carb on my HD6's and would love to get rid of the thing and go to a manual choke, Burlen sell the components to do the job at about £500 plus vat but it is supposed to be very involved.
So I thought about fitting HS6 carbs instead of the HD6's but were told that they will not fit.
Has anybody fitted the manual choke conversion to the HD6's or able to explain to me why the HS6's will not fit.
And when I say manual choke I mean a cable choke not simply switching the thing on and off when needed.
I have a 66 3.8.

Many thanks

 

Check the Moss Motors catalog for the Austin Healey early 3000s that used HD6s. A manual choke was used on the carbs. The catalog (look on-line) shows the choke components. You will need the proper lower piece for the front float bowl - not the Jaguar one that feeds the starting carb. They are interchangeable. Hope that helps.
Lin

 

I have not done this myself but you need to replace item 58 (Jet Housing Assembly) in this diagram in both HD6 thermo carbs so you can manually pull down the jets on their diaphragms with one of these from Burlen. (AUC 8654)



AUC 8654



Then you can fit a slider from a Mk2 with Solex carbs, A Bowden cable & the necessary inner and outer cable clamps on the carbs similar to E Type.

 

I'm going to resurrect this thread.
Glyn, when entering that part number at Burlen, it says it's for the HD8, will it also fit the HD6 carburetor ?

HD8 Jet Housing Centre - SU Carburetters

 

Well as shown in the HD6 Thermo diagram above it would appear so. That's where I got the number from unless it's an error or merely indicates that it is normally associated with HD8's. As mentioned by MK2 above the Healey 3000's used manual chokes with HD6's.

I guess to make sure one should contact Burlen. As I say I've never done this. As long as Part number 58 in the diagram is still available this should be doable. One should check that Part 58 is in fact AUC 8654 as it was when I first checked.

 

The only problem that I had with the starting carb was the thermo switch not switching. I resolved it with some cable to a manually operated switch inside the car. It's easy and inexpensive.

 

As many do. They delete the Otter switch in the manifold and switch the AED manually. Mine works fine as originally designed & I always keep a spare Otter switch. Many have starting issues because they don't set up the needle in the AED for their ambient conditions (i.e. adequate enrichment.)

No 2 in diagram.

 

I gave up on the otter switch mainly because it seemed to fail to switch off in the worst places, such as in the queue coning off a North Sea ferry. Everyone had to wait while, I got out of the car, lifted the bonnet, pulled off the cable, closed the bonnet and re-started. Though it may have been the quickest fix most had ever seen.

It never failed outside the house.

 

I left the Otter switch in place but it is the main cause of the choke failing to work correctly. If the Otter switch fails it can either leave the AED permanently on or permanently off. What I fitted was a switch on the dash which is actually a second rear screen switch I picked up at an auto jumble as this has a warning light and looks like it should be there. I had a new Escutcheon made to read CHOKE rather than REAR WINDOW. When I want to start the car I pull the switch which sends power and turns on the AED. If I forget to switch it off the Otter switch kicks in and switches it off for me but generally as soon as the car is moving I just push in the button and the AED is switched off.
Works for me.

 

I'm not fitting the Otter Switch or the starting carburetor, never liked the at set up.
Island Automotion has some jet bodies from a MK X that I can convert to what is in post three.
I would buy the part from Burlen, but at £116.00 for each carb, that's a bit excessive.

https://www.sucarburetors.com/

 

Yes ~ pulling down the Jet for enrichment would seem the most sensible & simple to execute route. It might shorten the diaphragm life slightly but is of no real consequence.

If I was having trouble with my thermo/AED arrangement & starting from scratch it is probably what I would do. One does not hear E Type owners complaining about this manual system of enrichment.

Ouch! ~ Burlen is not shy to charge. Maybe you can find some used ones from scrapped carbs.

 

I don't have the patience to deal with scrap yard dealers.

I'll tell everyone the whole story, the carbs are not for my 340 Jaguar, but for my MK VI Bentley.
The carbs on there now are H6, they have a tendency to leak fuel out the bottom of the main jet.
The balance and idle are adjusted from the main butterfly valve and is very difficult to achieve this with the hokey Rolls Rolls linkage in the middle.
Adjusting the mixture is also a pain because the big nut used to achieve this is difficult to get to and is not very precise.

There are a few other reasons too, but those are the main ones.

I could use the starting carburetor, but that would mean removing the intake manifold and drilling and tapping holes in it; something I don't want to do.

 

Understood ~ paying Burlen might be worthwhile then. Your choice if you choose to go ahead.

 

You might want to look at HIF44 carbs too, they were used on Mini's, as well as the Daimler DS420 limo with a manual choke.

 

Thanks, but I think the bolt pattern on that model will not match up to my air horn.

 

Jeff, An alternative to scrap dealers is someone like Ken Jenkins. He has a good stick of NOE and re-cycled parts. He's also an excellent source of information and advice. He and his daughter who works with him are also as nice people as you can hope to find.

Also, original SU can often be better quality than more recent repro/remanufactured.