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Worn-out Tillotson ML carbs - fixes? Parts?

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spoon55432

On Training Wheels
I have a couple H motors with Tillotson ML carbs that both have throttle shafts that are so worn out they have more than 1/32" of play when wiggled. They are leaking a lot of air around the shaft, so much that I can't control the idle. I'm trying to fill cavities in the worn brass shaft with JB Weld and/or might have a couple new ones machined. Wondering if this is a common problem and if so how do people deal with it, or does anyone have old (good or NOS) Tillotson carb parts? I like to keep it all original & stock. Haven't been able to find much of anything used.
 
I've seen where Teflon shims have been used to remedy a vacuum leak at throttle shafts on automotive carbs. A better way to fix it is to drill out the body for a slightly larger diameter throttle shaft.
 
I've seen where Teflon shims have been used to remedy a vacuum leak at throttle shafts on automotive carbs. A better way to fix it is to drill out the body for a slightly larger diameter throttle shaft.
Strangely enough, most of the wear seems to be on the brass shaft and not the carb bushings. I can get the shaft reproduced by a friend, but just looking to see what's out there.
 
The Cushman Scooters used Tillotson ML carbs. Denis Carpenter has replacement parts for them:
Note that some slight adjustments/modifications MAY be necessary:

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Ream the holes out to assure the bores are clean and have oversize shafts made to fit or bore the holes out and fit bushings to suit new original diameter shafts.

either way, its time to get friendly with the local machinist if you don’t have the skills and/or the nerve.

I once had to drill a 3/8” hole in the side of a brand new carb... My blood pressure still spikes when I think of that task.
 
I took a quadrejet to rebuilders and returned as he was assembling baseplate. . After installing the oversize bushings the casting cracked . He insisted that it was too bad, while I told him it wasn't cracked when I brought it to him. I'm afraid I might have to take a 69 core for him to work his magic.
 
I took a quadrejet to rebuilders and returned as he was assembling baseplate. . After installing the oversize bushings the casting cracked . He insisted that it was too bad, while I told him it wasn't cracked when I brought it to him. I'm afraid I might have to take a 69 core for him to work his magic.
Sounds like he went for too tight a fit on the bushings or used a hammer instead of a press to put them in. With today’s adhesives I’d go for a looser fit and use some of Henkel/Loctite’s magic goop to secure it.

Mmmmm... quadrajet.... haven’t heard that name in a while. First carb I ever worked on was an MV4 Quadrajet on a 69 Buick Wildcat. I learned to drive in that big brute, it would glide around town majestically like a Cunard liner until you dropped the hammer, then it would pick its skirts up and disappear over the horizon like a raging bull. With all four barrels open wide it sounded like it was going to suck the hood in... what a lovely thing!

kids don’t know what they’re missing these days!
 
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