Author Topic: Leaky Carb Question  (Read 2615 times)

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Offline Robbo

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Re: Leaky Carb Question
« Reply #25 on: May 31, 2018, 06:39:40 PM »
Yep, that gasket in the first pic looks all deformed.


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Offline Robbo

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Re: Leaky Carb Question
« Reply #26 on: May 31, 2018, 06:40:44 PM »
The face of the fuel knob looks good in the second pic.


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Offline aaguilar3

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Re: Leaky Carb Question
« Reply #27 on: May 31, 2018, 08:14:31 PM »
I emailed 4into1. Not sure if they will send me a new one but I will try.

Yep, that gasket in the first pic looks all deformed.


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Offline aaguilar3

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Re: Leaky Carb Question
« Reply #28 on: June 01, 2018, 10:06:03 AM »
4into1 states they checked and all their kits look fine. They stated they would send me a new kit.

Offline BobR

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Re: Leaky Carb Question
« Reply #29 on: June 01, 2018, 02:24:18 PM »
I lightly flat sanded and polished my lever surface. Mine stopped leaking after that though my rubber wasnt deformed looking like yours. Might help keeping the rubber nice though.Bob
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Offline bryanj

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Re: Leaky Carb Question
« Reply #30 on: June 02, 2018, 05:10:44 AM »
The correct fibre washers (thick) under the heads of the retaining screw are vital or gas will leak down the threads and straight into the carbs, I have never found suitable aftermarket ones and Honda charge a fortune but I have used the small alloy ones with rubber inside seals form hydraulic fittings(called Dowty Washers in UK) with some sucess
Semi Geriatric ex-Honda mechanic and MOT tester (UK version of annual inspection). Garage full of "projects" mostly 500/4 from pre 73 (no road tax in UK).

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Offline aaguilar3

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Re: Leaky Carb Question
« Reply #31 on: June 04, 2018, 05:37:56 PM »
I got the new rebuild kit and it still let's gas dribble out. I'm giving up. I've run out of what to do.

The correct fibre washers (thick) under the heads of the retaining screw are vital or gas will leak down the threads and straight into the carbs, I have never found suitable aftermarket ones and Honda charge a fortune but I have used the small alloy ones with rubber inside seals form hydraulic fittings(called Dowty Washers in UK) with some sucess

Offline piefairy

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Re: Leaky Carb Question
« Reply #32 on: June 04, 2018, 06:06:22 PM »
A small drip from the petcock valve I dont thing would be an issue. You cant think of it like and ON/OFF switch, but more like narrowing down a tunnel. It will never be completely closed, but ideally the surface tension of the fluid will prevent a leak. The more gas in the tank, the more pressure against the surface tension of the fluid at the petcock, and the more likely to leak.

How much is a "dribble"? A drop or two every few seconds without the fuel line connected to the carbs I would imagine would be acceptable since you would get a small bit of back pressure due to the distance, constriction and hosing and small vents at the carb.

Offline Robbo

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Re: Leaky Carb Question
« Reply #33 on: June 04, 2018, 06:10:04 PM »
Suggest you try replacing the gasket with the OEM Honda part.  I never had an issue using a genuine honda fuel tap gasket.


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Offline aaguilar3

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Re: Leaky Carb Question
« Reply #34 on: June 04, 2018, 06:48:35 PM »
It's about a drop a second and the tank isn't full

A small drip from the petcock valve I dont thing would be an issue. You cant think of it like and ON/OFF switch, but more like narrowing down a tunnel. It will never be completely closed, but ideally the surface tension of the fluid will prevent a leak. The more gas in the tank, the more pressure against the surface tension of the fluid at the petcock, and the more likely to leak.

How much is a "dribble"? A drop or two every few seconds without the fuel line connected to the carbs I would imagine would be acceptable since you would get a small bit of back pressure due to the distance, constriction and hosing and small vents at the carb.

Offline piefairy

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Re: Leaky Carb Question
« Reply #35 on: June 04, 2018, 07:11:33 PM »
Have you checked the gas cap? If the seal is not "good" it may cause issues. I've never run into this on non-fuel pump systems, but I suppose it could be a factor when balancing the fuel flow.

Offline jonda500

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Re: Leaky Carb Question
« Reply #36 on: June 04, 2018, 10:57:58 PM »
The correct fibre washers (thick) under the heads of the retaining screw are vital or gas will leak down the threads and straight into the carbs, I have never found suitable aftermarket ones and Honda charge a fortune but I have used the small alloy ones with rubber inside seals form hydraulic fittings(called Dowty Washers in UK) with some sucess
^^ this! if the mounting screw fibre washers are leaking fuel will dribble out regardless of the position of the fuel tap.
John
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Offline aaguilar3

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Re: Leaky Carb Question
« Reply #37 on: June 05, 2018, 07:11:27 AM »
Which washers are these? The ones that are used for the 2 screws to attach the petcock to the tank?


The correct fibre washers (thick) under the heads of the retaining screw are vital or gas will leak down the threads and straight into the carbs, I have never found suitable aftermarket ones and Honda charge a fortune but I have used the small alloy ones with rubber inside seals form hydraulic fittings(called Dowty Washers in UK) with some sucess
^^ this! if the mounting screw fibre washers are leaking fuel will dribble out regardless of the position of the fuel tap.
John

Offline Robbo

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Leaky Carb Question
« Reply #38 on: June 05, 2018, 07:32:15 AM »
Yes that’s what he is talking about.  One fibre washer for each of the two mounting screws.


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« Last Edit: June 05, 2018, 07:37:11 AM by Robbo »
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Offline aaguilar3

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Re: Leaky Carb Question
« Reply #39 on: June 05, 2018, 08:47:51 AM »
Ok, I think they might have the dowty ones at Lowe's. I'll see if I can give it a shot one last time.


Yes that’s what he is talking about.  One fibre washer for each of the two mounting screws.


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Offline aaguilar3

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Re: Leaky Carb Question
« Reply #40 on: June 05, 2018, 07:06:20 PM »
I ended up putting back on the original washers and it stopped leaking  :)

Offline bryanj

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Re: Leaky Carb Question
« Reply #41 on: June 06, 2018, 07:47:05 AM »
Am I allowed to say told you so
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Remember "Its always in the last place you look" COURSE IT IS YOU STOP LOOKIN THEN!

Offline aaguilar3

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Re: Leaky Carb Question
« Reply #42 on: June 07, 2018, 07:55:15 AM »
 :) Yes, you definitely can. That's how I learn lol.

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Offline BobR

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Re: Leaky Carb Question
« Reply #43 on: June 07, 2018, 10:15:32 AM »
 Yeah I went back to the fiber ones myself along the way of getting mine to work correctly. I had used some loctite on the aluminum ones so they werent leaking but I didnt trust them.. Didnt trust the fiber either though and used a dab of red loctite on them too, lol.
Glad you got it sorted out! Bob
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Offline techy5025

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Re: Leaky Carb Question
« Reply #44 on: June 10, 2018, 02:42:39 PM »
The correct fibre washers (thick) under the heads of the retaining screw are vital or gas will leak down the threads and straight into the carbs, I have never found suitable aftermarket ones and Honda charge a fortune but I have used the small alloy ones with rubber inside seals form hydraulic fittings(called Dowty Washers in UK) with some sucess

Amen. My fibre gaskets looked fine....and leaked. The bad thing is that even if the fuel shut off valve is working correctly...stopping flow from the tank in the off position, if you need to remove the petcock bowl to clean it out fuel will still run thru the screw threads and leak.  If you plug the hole in the middle of the filter mesh where gas enters the bowl and you still have a leak, the fiber washers are the reason. If you don't, it's the shutoff valve itself. With the bowl off of course.

I did have one screw that had a manufacturing defect that left a metal burr on the bottom of the screw head. The fiber washer could not seal against that causing a leak. Fileing it off fixed the leak.

Jim
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Offline aaguilar3

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Re: Leaky Carb Question
« Reply #45 on: June 15, 2018, 07:21:40 AM »
So mine started to leak again shortly after I thought I had fixed it. Took it apart and only had one place it was leaking from. The hole that leads from the shut off to the bowl. I had already replaced the gasket and spring washer. So after inspecting the back of the lever I noticed it was uneven slightly towards the top center and figured that tiny bit might let those few drops by. I remember someone on the thread had mentioned flat sanding the back. So I tried this and it worked!! For now at least lol.