Author Topic: Question about CB750 carbs, vent hose  (Read 1049 times)

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Offline Eydugstr

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Question about CB750 carbs, vent hose
« on: January 31, 2016, 02:38:19 PM »
Hello, working on a set of CB750 carbs (K1 - K6 style), and the vent hose nipple came out of one of the carb castings.  It fits fairly tight, but is there anything you guys use (epoxy, jb weld?) to cement them back into place, to cut down on a possible vacuum leak?

Offline harisuluv

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Re: Question about CB750 carbs, vent hose
« Reply #1 on: January 31, 2016, 03:06:31 PM »
No.

The purpose of that circuit is to equalize pressure, vacuum leak doesn't really apply.  Basically air equalization from there is what you WANT.

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Question about CB750 carbs, vent hose
« Reply #2 on: January 31, 2016, 03:32:45 PM »
Maybe some Hondabond etc just to prevent it's potential loss if it comes out. I just wedged mine in.
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Offline Eydugstr

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Re: Question about CB750 carbs, vent hose
« Reply #3 on: February 03, 2016, 01:06:53 PM »
No.

The purpose of that circuit is to equalize pressure, vacuum leak doesn't really apply.  Basically air equalization from there is what you WANT.

TY.  That makes sense.

Maybe some Hondabond etc just to prevent it's potential loss if it comes out. I just wedged mine in.

TY, Jerry.  I'll try to widen the brass insert out with a nail, then see if it stays in the carb body a little better. 

Offline flybox1

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Re: Question about CB750 carbs, vent hose
« Reply #4 on: February 03, 2016, 01:26:35 PM »
You could just score the outside of it enough to give it some bite as you press it back in.
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Offline 754

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Re: Question about CB750 carbs, vent hose
« Reply #5 on: February 03, 2016, 01:40:34 PM »
Be careful if ...if, it has a taper on it,  then just clean well and tap it back in..
 Not sure if it is but a taper will not like the things mentioned above..
 Petcock outlets used the taper in many cases.
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