HS4 sticking choke

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Mark Wilson
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HS4 sticking choke

Post by Mark Wilson »

I know I'm not the only one on here who has an HS4 with the conversion to remove the waxstat. (The SU kit that is, not the 2p coin trick!) Since doing mine the choke mechanism has tended to stick down without fully returning the jet to its seat.

Last night I googled this and found that it seems to be a fairly common problem for MGs and Triumphs. One answer suggested was lightly polishing the outer face of the jet with fine wet and dry, or metal polish. I've done mine today with 2000 grit, followed by Brasso and lubricated with WD40.

It works!
Mark Wilson
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Re: HS4 sticking choke

Post by Mark Wilson »

Oh no it doesn't! Sticking again - if anyone has any way of making the conversion linkage work please let me know :roll:
Mark Wilson
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Re: HS4 sticking choke

Post by Mark Wilson »

Just for the record, I've reverted to the waxstat jet, but with the two pennies conversion. Not at all impressed with the official conversion, very badly designed linkage.
philthehill
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Re: HS4 sticking choke

Post by philthehill »

Could you please post a link to the conversion kit to enable the RED jet to be fitted.
I note that the choke linkage for the wax stat jet and the RED jet are totally different. Perhaps fitting the correct SU choke linkage for the RED jet may be the answer.

Mark Wilson
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Re: HS4 sticking choke

Post by Mark Wilson »

Hi Phil. It was a few years back and I can't remember where I obtained the red jet and linkage from, but the linkage doesn't seem to be "official", ie Burlen, as I thought. They look like this image off the internet.
proxy-image.jpg
proxy-image.jpg (24.93 KiB) Viewed 3302 times
The current adverts for this type feature a modified attachment and spring behind the quadrant, like this

http://www.minispares.com/product/Class ... 01SUL.aspx

From memory mine didn't have this modification, I think I attached the top of the vertical rod to the original linkage attachment point, which I think is as the internet photo. I do remember struggling to get the double spring arrangement correct, so may not have got it completely right. It worked most of the time, though, so can't have been too far out. I've now replaced the whole carb with an HS4 restored by someone else, and it will remain unmolested by me, other than replacement of the waxstat capsule with two pennies!
philthehill
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Re: HS4 sticking choke

Post by philthehill »

Mark
Thank you for the information.
I have a HS4 with waxstat which I intend to convert to the standard jet arrangement in due course so the information is very helpful.
Re the photo above - I am interested to know why the replacement link has to be so convoluted and has to enter the jet choke linkage pivot point from the opposite side to what would be the natural lay of the choke operating rod??
No wonder it sticks. :-?

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