Sprint carbs

[RoySne]

Hi all,

I’ve had my dolomite Sprint for 6 years. This is the second sprint I’ve owned. In the sevenths I had a magenta coloured one. The reg is WDN186R. I believe it was first registered in York. I would very much like to find out more about it.
I have also found these su carborettas. The metal tag in the side has the letters AUD663R are these SU 6.









Hope you can be of some help, happy new year to you all

Roy

[GrahamFountain]

I was also first registered in York, but that's as near as I come to your Sprint.
The carbs are SU HS6s from a Sprint from after 1976. The tag on the left carb float chamber top, which seems to be in the right place, should say AUD663L. The set looks to be just missing the throttle linkage and rubber tubes.

Graham

[soe8m]

I was also first registered in York, but that's as near as I come to your Sprint.
The carbs are SU HS6s from a Sprint from after 1976. The tag on the left carb float chamber top, which seems to be in the right place, should say AUD663L. The set looks to be just missing the throttle linkage and rubber tubes.

Graham

These are the pre 1976 type carb bodies.....

Jeroen

[GrahamFountain]

Burlen Fuels have AUD 663 L&R as 1976 onwards.

http://sucarb.co.uk/carbspec/carburetto ... s/id/2469/

Maybe the tags are wrong if the bodies are earlier, though I'm not clear on what the visible differences are.

Graham

[soe8m]

It's easy to see. Early cars have the idle screw through the carb and the later type in the carb. The casting is different. The HS4 of the 1850 had the same modification.

Not sure of these are all Triumph carbs but on the pics you can see.

Jeroen

[GrahamFountain]

So are you saying that they are not AUD663's or that Burlen Fuels are wrong about the 663s being 76 on?

Graham

[soe8m]

So are you saying that they are not AUD633's or that Burlen Fuels are wrong about the 633s being 76 on?

Graham

Not late ones. Early type body. The rear one isn't even a Triumph Dolomite Sprint one, looks like a Volvo one.

Jeroen

[GrahamFountain]

I assume this is what you mean by the adjuster in the body, shown on a carb on one of Beans' TR7s.



The adjuster screw usually has two orthogonal straight-cut slots (not like a Philips) and, I believe, BL sometimes put an anti-tamper plug in the hole above the adjuster, cos some folk are just mean like that.

But I looked at the AUD 663's I have, and they have the idle adjusters as a setscrew with a slot in the head, through a flange on the body, with a locknut; not recessed into the body. The difference I do know is that some AUD 545s don't have a brass tube on the overflow on the float chamber cap, so you can't fit the overflow pipe. So if the float needle jams there's fuel all over the place.

So I though it might be meaning one of the other later carbs, e.g. FZX 1257, you mean as "later carbs", which I have none of. But Burlen Fuels show that carb also having the idle adjuster as a setscrew and locknut - but they could be wrong of course. So I don't know which later Sprint carbs have the recessed idle screws in the body. But it's not AUD 663s, as these are tagged.

BTW, which bit is it appears to be Volvo?
I admit I don't recognize the plastic clamp on the rear carbs float chamber top, but that's a bit on a bit on a bit connected to the body, not the body.

Graham

[GrahamFountain]

Looking again at FZX 1257 on Burlen Fuels, that shows a carb without Waxstat Jets. Isn't that wrong for the FZX 1257?

So maybe the FZX 1257 is the later one with the adjuster recessed into the body, and the pics on that site are not quite right. gRimmers appear to show the FZX series carbs as having a recessed adjuster, though they don't list AUD 663 for the Dolomite Sprint. Though I remain fairly sure the AUD 663s have the setscrew through the flange.

But thinking about it, don't some AUD series carbs have a spring on the setscrew above the flange, like Burlen show on the FZX 1257, not a locknut like I've got on my carbs? Didn't look as closely at that picture as I should, did I?

Graham

[GrahamFountain]

Sorry, but I noticed I'd made a typo partway through this thread and put AUD 633 instead of AUD 663. Worse still, I then looked back at that errored post instead of the OP, and kept using 633 instead of 663.

I've corrected it where I can, hopefully reducing the potential for confusion later.

Graham

[GrahamFountain]

Found a pic of a pair of FZX 1257, and they do have the recessed idle adjusters in the body.



But the AUD 663 are also later carbs after 1976 and have the setscrews through the flange like the early ones.

Graham

[GrahamFountain]

It occurred to me overnight that the reference to Burlen Fuels didn't show for certain that AUD 663 is a later (after 1976) carb set for the Sprint, and FZX 1257 might be the only one. So I dug out the SU Catalogue 1969-1983, LZT 8032, and here's a scan of the section covering the Dolomite Sprint:



So I think that shows that not all later Sprint carbs have the idle screw in the body. So, from the AUD 663 tags, these carbs are indeed off a Sprint after 1976, as I wrote right at the start, despite the rear one having a replacement float chamber cover.

It might be interesting if one of the spares lists someone has shows which chassis number ranges or specs after 1976 have AUD 663 and which have FZX 1257.

Graham

[soe8m]

The choke cable tube/holder and the plastic part both on the rear carb makes it Volvo for me.

Jeroen

[GrahamFountain]

That the float chamber top is not original I'll grant you. But, by the "choke cable tube/holder" do you mean the one like this on my own Sprint carb set?



Also, what about the point that AUD 663s don't have integral idle adjusters and yet are later, i.e. 1976 and after, carbs? That feature being indicative of the FZX series of SUs.

Graham

[soe8m]

That the float chamber top is not original I'll grant you. But, by the "choke cable tube/holder" do you mean the one like this on my own Sprint carb set?



Also, what about the point that AUD 663s don't have integral idle adjusters and yet are later, i.e. 1976 and after, carbs? That feature being indicative of the FZX series of SUs.

Graham

Originally the front carb has the tube and the rear not. The choke cable attaches to the front carb. I believe that is with all Triumphs, also the big 6's and the 1850's.

I do not know any date or commission numbers when the carbs changed. The 1850's the change was around 1976, early/late. The sprint maybe a year later but I don't know exact dates. I know the early sprints have the screw through the carb and the later ones I have seen or had, had just like the later 1850's the screw in the carb housing.

http://sucarb.co.uk/cf/vehicle/list/?ma ... e=Dolomite

I'm not sure how accurate these lists above are.

Jeroen