Unsolvable Vacuum Leak 1980 cb750 Custom

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Unsolvable Vacuum Leak 1980 cb750 Custom

Wrench Nick
Hey guys I recently picked up a 1980 cb750 custom. I've had it for a month now and the only issue with it is the vacuum leaks coming from the carb manifolds. I bought brand new OEM boots because the old ones were original and rotting. I figured this would solve my problem but all of the boots still have vacuum leaks. Is there a seal or something that I need to put on the motor and carb before installing the boots? I've tried using silicon to make a seal but that didn't work. I then tired using gasoline tap to wrap the carb and motor before slipping the boots on. Once again no luck and the leaks still persist. Does anyone have a solution?!
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Re: Unsolvable Vacuum Leak 1980 cb750 Custom

TOOLS1
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Two things come to mind here. First, the clamps could be stretched and not able to clamp the boots tight enough. Second, the caps on the vacuum ports might not be sealing.
TOOLS
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1976 CB 750-A X 2
1977 CB 750-A X 4
1977 CB 750-K
1976 CB 750 F
1981 CB 750
1966 Kawasaki SG 250
1981 KZ 750 LTD
1973 CB 350
1979 CM 185 Twinstar
1982 Honda XL 80
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Re: Unsolvable Vacuum Leak 1980 cb750 Custom

Re-run
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Yep, I would look at those first, too. The clamps are known to stretch.
The ride IS the adventure. The destination is just to get gas!