Author Topic: how i fixed my cracked carb boots  (Read 14222 times)

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Offline neil young

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Re: how i fixed my cracked carb boots
« Reply #25 on: May 19, 2008, 01:03:59 PM »
seems to be working out great....test jar is holding up well.....no change in 4 hours.
if it will hold up on straight gas immersion then the fumes dont have a chance ::).....fingers crossed.
1972 CB500 k1
1974 CB550
1977 cb 550
82 suzuki GS 750tz.......16  valves  baby
2008 Triumph Scrambler

Offline Gordon

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Re: how i fixed my cracked carb boots
« Reply #26 on: May 19, 2008, 01:04:45 PM »
curious to see how this works out!  :o  :D

Rachet~

Me too!!  Think of the endless possibilities.  Hell, you could just coat the whole damn bike in the stuff and protect it from everything! ;D

And why stop there?  If you're going for a long ride in suspect weather just paint it over your naked body and the peel it off when you get home.  You might even make some new friends along the way! :o :D

Offline TwoTired

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Re: how i fixed my cracked carb boots
« Reply #27 on: May 19, 2008, 01:06:40 PM »
Update:

The coated screw has been in gas for five hours now and so far the liquid tape is showing no changes. 

Chances are, if the dried substance withstands immersion, vapor probably won't hurt it either.  It's just that, in this case, "where used" doesn't normally have immersion characteristics.

Do we care about UV exposure?

Maybe I was an engineer for too long... ::)

Cheers, ;D
Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

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Offline neil young

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Re: how i fixed my cracked carb boots
« Reply #28 on: May 19, 2008, 01:10:42 PM »
its past the uv exposure test.....read back a few posts ;D
my rear signal wires are hanging out there in the full sun....and no problems with the liquid tape after a year.
nice try though Loyd (party pooper) ;D
1972 CB500 k1
1974 CB550
1977 cb 550
82 suzuki GS 750tz.......16  valves  baby
2008 Triumph Scrambler

Offline Soos

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Re: how i fixed my cracked carb boots
« Reply #29 on: May 20, 2008, 12:06:04 AM »
Liquid electrical tapa is amazing stuf.

I used a bit to help "seal up" my wiring harness.
Probably a bit of overkill, but if water has a harder time getting to my wires, i'm happy.
If it prevents one short/electrical problem in the future, it was well worth it.

Interesting use for airbox boots though.


Speaking of this stuff, has anyone ever tried rubber tool handle dip for this?
I bought a can lately to get new grips on a few older handtools, and have been thinking it may well serve the same purpose.... but i have no idea if it will hold up to gas....
Would be interesting to have blue coated airbox boots...


l8r
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Offline Tower

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Re: how i fixed my cracked carb boots
« Reply #30 on: May 20, 2008, 01:00:33 AM »
According to the spec sheet that neil young posted...in case someone missed it...the main ingredient of Star brite Liquid Electrical Tape is vinyl chloride/vinyl acetate co-polymer...i.e. PVC.

PVC is gasoline stable only if its boronated or sulphinated.

Offline Dave-and-his-550

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Re: how i fixed my cracked carb boots
« Reply #31 on: May 20, 2008, 02:58:35 AM »
According to the spec sheet that neil young posted...in case someone missed it...the main ingredient of Star brite Liquid Electrical Tape is vinyl chloride/vinyl acetate co-polymer...i.e. PVC.

PVC is gasoline stable only if its boronated or sulphinated.

Hmmm, so that means its a no go? Cause my airbox to carb rubbers are falling apart, and I was hoping to try this tomorrow :(

Offline Gordon

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Re: how i fixed my cracked carb boots
« Reply #32 on: May 20, 2008, 03:34:59 AM »
Still holding up fine in the jar o' gas.  I'll check it again when I get home from work.

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Re: how i fixed my cracked carb boots
« Reply #33 on: May 20, 2008, 05:47:39 AM »
According to the spec sheet that neil young posted...in case someone missed it...the main ingredient of Star brite Liquid Electrical Tape is vinyl chloride/vinyl acetate co-polymer...i.e. PVC.

PVC is gasoline stable only if its boronated or sulphinated.

Yeah, what he said, and I'm confuseicated... ???

Offline Tower

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Re: how i fixed my cracked carb boots
« Reply #34 on: May 20, 2008, 08:28:52 AM »
The emersion/suspension includes chemical names I don't recognize as they are branded.  These chemicals may be giving the PVC a little of that boron resistance I mentioned, but I can't tell by the names (e.g. Lenplas ESO-1, K-Flex, Pliolite AC-4).  Judging by the names only - its possible they keep the PVC pliable by bonding it to something like a boron acetate.  The other ingredients are standard industry solvents, driers, hardeners, lubricants and colour.

Offline neil young

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Re: how i fixed my cracked carb boots
« Reply #35 on: May 20, 2008, 02:37:36 PM »
i have had the starbright in a jar filled with gas for 36 hours with no change at all.....still solid. ;D 8)
i would say it has past the test.....this is the product on the underside of the dry lid with gas in the jar.
lets see what Gordon's test shows.
1972 CB500 k1
1974 CB550
1977 cb 550
82 suzuki GS 750tz.......16  valves  baby
2008 Triumph Scrambler

Offline Gordon

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Re: how i fixed my cracked carb boots
« Reply #36 on: May 20, 2008, 03:21:52 PM »
i have had the starbright in a jar filled with gas for 36 hours with no change at all.....still solid. ;D 8)
i would say it has past the test.....this is the product on the underside of the dry lid with gas in the jar.
lets see what Gordon's test shows.


Home from work, finally! :)

I just removed the coated screw from the gas after 33 hours of immersion.  The only change I can detect is that it's not quite as shiny as it was to begin with, but other than that it still retains the exact same consistency, adhesion, and pliability that it had before the test. 

I'm reserving final judgment until it's had a chance to dry completely, though.  There's the possibility that the gas is what's keeping it pliable right now and it still might dry up and crack into pieces.

I'll report back later tonight, but Neil's fix may just turn out to be the greatest discovery of the 21st century!!!!! ;D :D ;D :D 

Offline neil young

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Re: how i fixed my cracked carb boots
« Reply #37 on: May 20, 2008, 03:27:11 PM »
heh....i should clean up the garage more frequently ;)
1972 CB500 k1
1974 CB550
1977 cb 550
82 suzuki GS 750tz.......16  valves  baby
2008 Triumph Scrambler

Offline nilsey

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Re: how i fixed my cracked carb boots
« Reply #38 on: May 20, 2008, 03:45:52 PM »
don't knwo if this is already out there but here is a source for airbox to carb hoses:

http://www.northcityvintagehonda.com/servlet/the-211/honda-cb500-cb550-air/Detail

 i bought pods before i saw these -- i had searched high and low but couldn't find them.

well, here they are!

1976 CB550K: stock airbox, cb650 cam swap, 4x2 exhaust, dual disc brake conversion.
1974 BMW R90/6

Offline neil young

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Re: how i fixed my cracked carb boots
« Reply #39 on: May 20, 2008, 03:57:33 PM »
unfortunatly not for the 77 550 k  :'(
1972 CB500 k1
1974 CB550
1977 cb 550
82 suzuki GS 750tz.......16  valves  baby
2008 Triumph Scrambler

Offline Tower

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Re: how i fixed my cracked carb boots
« Reply #40 on: May 20, 2008, 04:22:00 PM »
Guys, you have to leave the pieces in the gasoline for like...a month...before there is  meaningful information.  For example, put gasoline in a used but clean chlorine bleach bottle and let it stand.  The bottle will be OK for a long time, but eventually it will begin to soften.  In about a month the bottle is perceptibly softer, and after two to three months it probably won't hold any liquid.  Until then it still looks like a chlorine bleach bottle.

Offline Gordon

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Re: how i fixed my cracked carb boots
« Reply #41 on: May 20, 2008, 04:33:24 PM »
Okay fine, be a stickler!! ;) ;D

I am actually going to leave it in there indefinitely, but I at least wanted to see if it had any short-term effect, and so far there is none. 

Offline Dave-and-his-550

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Re: how i fixed my cracked carb boots
« Reply #42 on: May 20, 2008, 09:25:09 PM »
Well as far as I know this is the only answer to fixing these:




Luckily, they too are the airbox to carb rubbers. So there couldn't be THAT much fumes right?....(right?)

Offline TwoTired

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Re: how i fixed my cracked carb boots
« Reply #43 on: May 20, 2008, 10:36:22 PM »
Those need to be replaced, I'm afraid, as they've lost their structural integrity.  The liquid vinyl might be OK for patching cracks not under stress, but they aren't going to re-bond the rubber together with high strength.
My opinion, anyway.


I'd bet those boots still had their clamps on during the carb installation/removal process.  This won't allow them the deflect during the operation and they tear, instead.
Cheers,
Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

Offline Dave-and-his-550

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Re: how i fixed my cracked carb boots
« Reply #44 on: May 21, 2008, 12:15:02 AM »
I'd bet those boots still had their clamps on during the carb installation/removal process. 

Too true, too true

Ya, I had them VERY loose, but not taken off, per the instructions provided to me from another link online...

I'll be checking Feebay for a set of them, or I could spend the $52 asking price on the link provided earlier from this site: http://www.northcityvintagehonda.com/servlet/the-211/honda-cb500-cb550-air/Detail

Offline Deltarider

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Re: how i fixed my cracked carb boots
« Reply #45 on: May 21, 2008, 03:10:33 AM »
Maybe you can persuade René van Maanen to ship to USA.

Go to http://nieuw.honda4.nl/, select Rubber, scroll down and you'll find a set of 4 new airchamber-to-carbrubbers for € 42,45.
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Offline TwoTired

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Re: how i fixed my cracked carb boots
« Reply #46 on: May 21, 2008, 08:56:11 AM »
Dave,
There is a another quarter inch or so to be gained by removing the two filter box mount bolts.  This allows the filter box/plenum assy to move rearward a bit.  Doesn't make it easy but it does make it easier.

Cheers,
Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

Offline Gordon

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Re: how i fixed my cracked carb boots
« Reply #47 on: June 04, 2008, 11:27:44 AM »
The experiment continues....

The Liquid Tape coated screw has been soaking in gasoline for 16 days now, and still no noticeable effects.  And since pictures are fun, I've included one of the aforementioned screw and "jar 'o gas". 





The best part is I got to eat the pickled okra first! :) :)

Offline CB750R

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Re: how i fixed my cracked carb boots
« Reply #48 on: March 15, 2009, 11:34:14 AM »
any long term updates on this?? I just picked up an 82 CM450 for the misses. and the boots from the carb to airbox aren't listed as a replacable part from honda and one is splitting down the middle lengthwise.

Offline neil young

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Re: how i fixed my cracked carb boots
« Reply #49 on: March 30, 2009, 07:45:20 AM »
my boot is holding strong.still flexable and sealed.
i still have the test in a jar with gas and no change after almost a year.
1972 CB500 k1
1974 CB550
1977 cb 550
82 suzuki GS 750tz.......16  valves  baby
2008 Triumph Scrambler