Post-War Other SU HS2 caburetor question

[TomMull]

I've got a pair of HS2 Carbs on my 69 Herald. The PO's mechanic, it would appear, stuck some solder on top of the little valves in the throttle plates (WZX1383 plates). I think that's why I can't seem to get one of them to shut down completely. I thought I'd just replace them but Moss wants about $90 for the pair. I think those valves had something to do with emissions (carbs might not be original). Anybody know if I'm right? I don't see them in the Herald catalog so might be US only. Any issues with just using the ordinary discs in place of them?
Tom

 

[titanic]

Tom-The spring loaded valves were part of the emission controls, designed to limit vac. on overrun . Most people replace them with the solid discs when rebuilding.
Berry

 

[TomMull]

Tom-The spring loaded valves were part of the emission controls, designed to limit vac. on overrun . Most people replace them with the solid discs when rebuilding.
Berry

Thanks, Berry. Got a pair of them on the way. I wonder if the valves indicate that the carbs are later than the 69 car?

 

[titanic]

I think emission controls started in 1968.
Berry

 

[Rut]

Tom,
post the AUD numbers on the carbs and we should be able to help.
Rut

 

[dklawson]

Remove the old disks from the butterfly shafts. Typically the valves are soldered to the disks. Heat the disks gently with a torch and snip the valves off with a pair of dykes. Fill the hole with solder and sand flat. Reinstall the plugged disks but don't tighten the little screws until you are sure the disks are oriented correctly and completely close off the carb throat. Look carefully to make sure you don't install the disks backwards. If backwards the beveled edge of the disk won't seat properly in and close the carb throat.

 

[TomMull]

Tom,
post the AUD numbers on the carbs and we should be able to help.
Rut

All I have are the casting numbers, AUC870 and AUC871. The little tags are long gone. Tom

 

[TomMull]

Remove the old disks from the butterfly shafts. Typically the valves are soldered to the disks. Heat the disks gently with a torch and snip the valves off with a pair of dykes. Fill the hole with solder and sand flat. Reinstall the plugged disks but don't tighten the little screws until you are sure the disks are oriented correctly and completely close off the carb throat. Look carefully to make sure you don't install the disks backwards. If backwards the beveled edge of the disk won't seat properly in and close the carb throat.

All makes sense, Doug, but I've put it back together and it runs, so will be waiting for the new discs which are cheap enough. Will pay close attention to the bevel etc. Thanks.
Tom

 

[Andrew Mace]

Sorry I'm late to the discussion. What your car has SHOULD be in every way identical to that of a 1969 model year "Federal" Mk3 Spitfire engine (hence the FF engine prefix compared to the Spitfire's FE prefix). I'd have to go dig in the barn to look, but I don't recall any such valves in the throttle plates, which does make me wonder if somehow your car did end up with later HS2s at some point?

EDIT: chalk it up to advancing age. After all, it's been 40 years this coming Halloween since my '69 Mk3 was last on the road! In fact, my carbs (as did all Spitfire carbs for the FE "emissions" engines) DO have those air valves. Are they really as bad as everyone has always said? I don't ever remember having any problems with them, but again, it's been 40 years this coming Halloween.... :tongue:

Oh, one more thing: you likely won't see information on these in any Herald catalog, as these "Puerto Rico" Heralds are not well documented. Engine-wise, you really need to think of this car as a "Federal" 1969 Spitfire Mk3. Same with the brakes (well, at least the master cylinder, that is)!

 

[TomMull]

Sorry I'm late to the discussion. What your car has SHOULD be in every way identical to that of a 1969 model year "Federal" Mk3 Spitfire engine (hence the FF engine prefix compared to the Spitfire's FE prefix). I'd have to go dig in the barn to look, but I don't recall any such valves in the throttle plates, which does make me wonder if somehow your car did end up with later HS2s at some point?

EDIT: chalk it up to advancing age. After all, it's been 40 years this coming Halloween since my '69 Mk3 was last on the road! In fact, my carbs (as did all Spitfire carbs for the FE "emissions" engines) DO have those air valves. Are they really as bad as everyone has always said? I don't ever remember having any problems with them, but again, it's been 40 years this coming Halloween.... :tongue:

Oh, one more thing: you likely won't see information on these in any Herald catalog, as these "Puerto Rico" Heralds are not well documented. Engine-wise, you really need to think of this car as a "Federal" 1969 Spitfire Mk3. Same with the brakes (well, at least the master cylinder, that is)!

Thanks for chiming in, Andy, your expertise is always welcome. While I've owned my TR3 for 51 years, I'm new to Heralds and Spitfires, but very interested.
The valves in my throttle discs were plugged by the PO, so I have no experience with them. I would probably have replaced them with originals had those been a bit less expensive.
Tom