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sticking butterfly

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weewillie

weewillie

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when I pulled the motor to replace it I found one of the butterflys sticking and not closing properly. An easy fix was to remove the shaft and build up the worn area with silver solder and file it round again. A 30 minute job and about about 25 cents worth of solder and propane.
 
Hope it sealed well. Air leakage will cause an idle problem.
 
Jack it was undercut on one side by about 15 thou, and now there is probably about a thou so any change would be an improvement
 
Oh, I am sure of that Willie. You did know you can get new standard or oversize shafts for about 12 bucks?

Good fix, will prob last years.
 
at least until I can afford to put a couple of webers on lol
 
[ QUOTE ]
at least until I can afford to put a couple of webers on lol

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That's where I'm heading Willie! These SUs remind me of my ex-wife, always wanting attention, expensive to maintain, useless in the morning and past their time.
 
You guys always talking trash about the SUs.

Keep in mind if set right with a good rebuild they will not need to be touched for years. They kind of like the energrizer rabbit.
 
I've never had too many problems with them even in 1963 when I had them on my Morris 1100
 
HS2s don't wear out shafts too badly because they ride directly on the aluminum carb body and not on a brass bushing like HS4s, so chances are you could just get two new shaft and two new butterlfies and fix them for not alot of money. I always get tickled at people who abandon SUs for Webers, the down draft is really a step back in performance and the side drafts are way more complicated than SUs every thought about being. SU parts are cheap, call Joe Curto he can get you anything you need.
 
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