Looking for a good, cost effective solution to remedy air leak.

Had a minor issue develop where the left side carb would pop every so often. It wasn't bad, but eventually got to the point where it was time to do something about it. Assumed it was the carb boots as they are original (32,000 miles) and are holding the weight of the carbs and Uni filters (stock carbs—rebuilt).

Got the carbs and boots removed. The boots appeared to have gaskets and a bunch of permagasket on them. Got the surface "de-gooped" and cleaned up nice.

Installed some JBM boots and their gaskets...figured that would take care of the problem. Nope.
It pops worse now. But, much easier to see exactly where the issue is. The leak appears to be up top where the gasket surface meets the head intake surface.

I mounted the carb boots and gaskets dry.

What are the best options for rectifying the situation?

Thanks,
JR

1978 XS650E

I'll use carb cleaner though the straw with the engine idling to pinpoint air leaks. Hylomar blue is my goto for "gotta seal" joints. Check the throttle shafts also. A carb overhaul isn't complete without new throttle shaft seals.

Did the carb cleaner thing as suggested. It revealed the leak on the top side on the left carb boot.
Got some Hylomar blue on order. Thanks for the suggestions, Gary!

Hint; don't goop it on, a thin, barely visible smear on the gasket is key. The big point of hylomar is that it seals but never "hardens". Been using it for 20 years, I'm on my second tube......

Will do!

Another good sealer (if needed) for intake gaskets would be permatex motoseal 1, probably available locally. It also never dries, and doesn't stick to anything, just fills the gap. It's a good substitute for yamabond, or better.

Those intake boots dont like to be tightened with all your might. Just snug then an 1/8th of a turn after is where I keep them. No leaks. The band clamp ends must be touching too that holds the carbs in the boot.

I kinda hate to even suggest this but... IF you are REAL careful. Often some PO has reefed on those bolts, that can raise the surface around the threads on the head flange. Easy and gentle only LIGHTLY run a fine file on the flange to see if the those areas are raised and with even, light strokes across the whole flange bring them back to flat. Put some paper towel in the intakes, vacuum before removing the paper towel when done. DO NOT use sandpaper here.

A thin coating of the Hylomar Blue did the trick. Thanks for the advice!

John