Author Topic: Fuel line question - 75 CB400F  (Read 228 times)

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Offline krksquared

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Fuel line question - 75 CB400F
« on: November 03, 2024, 11:11:45 AM »
Looks like a T fitting between the two center carbs is loose as can be seen by the linked video. Shouldn't be this way - right? I've never been this deep into the bike. O rings on the T? Looks like a bit of a struggle to get in there. Carbs need to come off? I don't like the idea of gas leaking in that area (or any other area)! Also, is 4.8mm fuel line hard to come by?

https://www.nostalgickitscentral.com/mustang/fuel%20line.mov
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1979 CBX
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Offline CycleRanger

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Re: Fuel line question - 75 CB400F
« Reply #1 on: November 03, 2024, 11:50:58 AM »
Yep, the carb rack has to come out and apart to change those o-rings.
The good news is Honda still sells the "packing set" (O-rings, gaskets) for those carbs.
PN 16010-333-315
They also sell the proper fuel line.
Do you have a copy of the Honda Shop Manual or Parts List for your bike? Get one here:
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Offline krksquared

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Re: Fuel line question - 75 CB400F
« Reply #2 on: November 03, 2024, 01:20:18 PM »
Thanks for the info! The things you discover when fixing something else  :o  Better now than later!
@kennectwithme
1975 CB400F
1971 SL350
1979 CBX
2007 Buell XB9R
2003 Harley V-Rod VRSCA
If it ain't broke, I'm riding...

Offline BenelliSEI

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Re: Fuel line question - 75 CB400F
« Reply #3 on: November 03, 2024, 02:30:30 PM »
If you don’t change the “0” rings on the tees, be patient. They may drip for a while, swell up and seat. Usually when that happens in the Spring, I make a note to replace them, next Winter!

Offline carnivorous chicken

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Re: Fuel line question - 75 CB400F
« Reply #4 on: November 03, 2024, 02:37:06 PM »
Also, these carbs are like other SOHC carbs where that T can wiggle a little, so the fact that it is moving isn't necessarily something bad. Better to see if it is actually leaking.
« Last Edit: November 03, 2024, 02:50:03 PM by carnivorous chicken »

Online bryanj

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Re: Fuel line question - 75 CB400F
« Reply #5 on: November 03, 2024, 03:07:38 PM »
Be very carefull with the tee, a lot are plastic and you cant buy it seperately
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Online Don R

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Re: Fuel line question - 75 CB400F
« Reply #6 on: November 03, 2024, 03:09:11 PM »
 I changed the tee on a KZ1000 and did remove the rack but only took two carbs loose enough to slip the tee out.
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Offline krksquared

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Re: Fuel line question - 75 CB400F
« Reply #7 on: November 03, 2024, 03:19:54 PM »
Hey you talked me into checking for leakage. I'd never noticed any leaking before but it's hard to see in there with the tank on and I always close the tank valve when parked. If I can get out of pulling the carbs, I'm all for that. And if I consume it faster than it leaks - no big deal haha. The only thing worse would be my CBX! Hmm maybe it's time to check that one too...
@kennectwithme
1975 CB400F
1971 SL350
1979 CBX
2007 Buell XB9R
2003 Harley V-Rod VRSCA
If it ain't broke, I'm riding...