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One more SU HS6 question

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Kentvillehound said:
How is it that the HS6s don't leak? They have no fiber washers or fiber gaskets, and no cork gaskets?
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Almost. They eliminated the rubber gaskets where the float bowl mounts to the carb body, plus the cork seals around the jet; which are by far the most common source of leaks on an H6. Instead, there is a plastic tube that carries fuel from the bottom of the float bowl directly to the bottom of the jet. The tube comes as part of the jet, and screws into the bowl, so it rarely leaks.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Randall, why is that little tool in the kit (expensive for aluminum) better than a Unisyn tool? [/QUOTE]Well, it's simple, cheap, accurate and rugged. Not sure what an SU tool kit goes for these days, but they used to be less than $10 while a Uni-syn was $50 or more. And the one that has been riding around in my tool box for over 20 years is still in good shape (although the plastic envelope and instructions are rather the worse for wear).

But the main thing I like is that it shows you that the throttles remain synchronized as the linkage opens them. This may not be important with the HS6 setup; but the original TR3 setup has the linkage attached at the front of the front carb, and the linkage between the carbs deflects somewhat under the force required to open the rear carb. The result is that, if you only follow the book procedure for synchronizing the throttles with the idle stops and then just tighten the linkage clamps; the rear carb lags slightly behind the front carb when you start to open the throttle. I feel this results in an engine that doesn't like to run smoothly with the throttle just cracked; like when idling through a parking lot or driving in a parade.

It's a minor difference to be sure; I am definitely not advocating that anyone throw away their Unisyn and run out to buy the SU tool kit. But having tried them both (the SU tool doesn't work on ZS carbs), I like the SU tool better. YMMV of course.
 
:thumbsup:
 
I have a quick question relating to my H6's on my TR3 --

Concerning the fuel mixture adjusting nut -- when I turn it completely clockwise, the nut never fully stops. Rather, as I continue to turn the nut, I see the lower jet bearing rotating with each turn. If I go counter clockwise, the nut will begin to loosen and the lower jet bearing will stop its rotation. Is this "the way it is supposed to be" or should the adjusting nut stop at a certain point? Is the engineering such that the big nut that locks the whole jet assembly in place supposed to put enough tension on the lower jet bearing to keep it from rotating? Many thanks for anyones help!
 
Yes, the big nut should clamp the jet bearing in place pretty firmly. If it doesn't, you may be missing one of the sealing rings, items 90 & 96. Or it may just not be tight enough to crush the cork gasket 97.

Be sure to check the jet centering again after tightening the big nut. It may take some fiddling to get everything just right.
 
Thanks so much for the input. I'm thinking I am going to just replace the entire jet bearing assembly with the illustration you posted. I'll check the tension on the big nut and make sure I have all the required pieces in there. Thanks!
 
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