Intake Leak

Hi My name is Jaime. I am going to school for my motorcycle tech certification and I am an intern at a Motorcycle Repair shop in Los Angeles. Because i am an intern, keep in mind, i have no money, so at this time i am looking for a solution where i can find the things i need either dirt cheep, or lying around at the shop i work at.
My 1981 kz440 belt drive has a bad intake leak at the intake boots where it meets the carbs. For a while i was just gunking it with silicone from the dollar store which was messy but would seal it up for a few days until eventually the hot cold cycle would be too much and one day i would start it and it was back.
When it comes back the bike hiccups horrible through the carbs and will take forever to warm up, will die with throttle until it gets driven a bit and is hot, and it lurches in first and second gears, hangs when i pull in the clutch etc. It is unsafe to drive when the leak comes back.
i recently cleaned off all of the silicon, pulled the carbs and the boots and the boots are not cracking, in fact they look pretty good. i used some high temp gasket sealant between the boots and the engine and when i started it, it was just as bad, if not worse.
so i put more on around the boots, a few ugly grey layers. The leak wasnt completely gone, when i sprayed carb cleaner it still hung up a little especially on the right cylinder, but it had stopped the popping and the hanging etc.
that was about two weeks ago, and i thought the high temp gasket sealant would last longer but it managed to break through again.
So what i am asking is, is there a better longer lasting way to seal up this leak?
As i said, the boots look like they are decent and the aftermarket boots are like 65 bucks, which i just cant afford, unless i dont want to eat for a week or two.
i dont mind putting on the ugly sealant, but because it comes back unexpectedly, usually in the morning after a cool down period, and i have to drive it to get to work in stop and go traffic, which is when the air leak causes the worst symptoms and as i said, they are bad enough to cause unsafe riding conditions.
Does anybody know of a longer lasting solution that may help me out until i can afford to buy new boots, maybe next month after school starts up and i get the financial aid money.
The boots do look to be pretty new.
Is it possible that when i pulled the boots off a couple of months ago ( i had bought the stock airbox and was trying to see if i could get it in through the front instead of through the seat)
that the rubber had shaped itself to the head and i maybe installed them in the opposite cylinders or flipped them from their original position and maybe if i take them off and switch them back it will go away.
so if u guys have any ideas to help me out, it is my only transportation. I would really appreciate it.
Jaime

Slicone sealant has it's purpose, but does not work well around high temperature situations on the cylinder head. I suggest removing the carbs,& carb holders(that's the part that goes between the carbs and engine). Remove any traces of the silicone and them find some of the original JB weld, a two part epoxy sealant/adhesive that once starts to set up,can be formed to make new sealing areas.

After it cures, it can be filed or smoothed down, or depending on how thick the build up is, drilled and tapped.

For leak checking, there are two ways; 1. The standard spraying around the boots and other rubber bits, seeing if the rpm's go up with brake cleaner or other light oils,and, 2. This method:


(Using An UNLIT Propane Torch For Vacuum Leaks)

Sorry I don't have a solution other than installing new carb holders, but I thought I might share my experience regarding the cracks. On my KZ650-C1 when the carb holders were leaking I looked them over and could see no cracks, in fact from the outside they looked like new. However, when I removed them and looked at the mating surfaces on the carb holders where they seal against the cylinder head there were VERY fine shallow cracks there which were barely visible except under magnification. I though they couldn't possible be causing the erratic idle I was experiencing, but after installing the new carb holders the problem totally disappeared. If you can look at the mating surface under magnification you may find yours also have these fine hairline cracks.

You may want to try Hondabond 4 or some similar non-hardening/non-silicone sealant as a temporary fix, but I don't know of a sealant that will permanently solve the problem. Ed

BTW, the genuine Kawasaki carb holders are still available so you don't need to go the aftermarket route. Ronayers.com lists them at $21 each.

If desperate for a temporary seal of an air leak between the carb holder and engine, would probably try
Permatex MotoSeal 1 Ultimate Gasket Maker Grey.

Where there's a suspected crack in the carb holder itself, it might also help to apply the product on both the inside and outside of the carb holder.

This product might or might not seal the leak any longer than whatever product has already been tried.

The challenge is finding a product that's both sufficiently heat-proof and gasoline-proof.

If used, please let us know the results.

Good Fortune!