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Original Leaky Petcock Question

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Dr. Frankenstein
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Posts: 568
Joined: Tue Feb 02, 2010 7:11 pm
Location: Charlottesville, VA

Original Leaky Petcock Question

Post by Dr. Frankenstein » Mon Jan 07, 2019 6:58 am

Has anybody solved the problem of using the original petcock on a 305? The one I have is in really good shape, but yesterday, while I had high hopes of putting the original tank on with the original petcock, I found that the original petcock selector lever was really loose; and while I was getting a positive flow from the petcock nipple, I was also getting a pretty decent drip from the petcock itself.

The petcock was rebuilt using a new rubber sealing kit with a rubber gasket inside, and also has a nice rubber O-ring between the tank and the petcock. Sealing washers were used around the three little screws inside,and I believe I had them tightened down pretty well, but I'm still getting drips out of the selector level slot, as well as the normal outflow nipple. Where is this coming from, and how can you cure it? I'd really like to use the original petcock just to stay with the look of the machine, but how can I stop this?

When I slide the selector lever to the "on" position, it flows well, and doesn't seem to drip as much; but when I put it in the Off position, I'm still getting a drip out of the nipple, as well as the selector lever slot. A leaky petcock!

I've heard some people are using cork gaskets, or replacing the petcock entirely with an aftermarket petcocock, but what are my options here?
Last edited by Dr. Frankenstein on Mon Jan 07, 2019 7:05 am, edited 1 time in total.

Dr. Frankenstein
honda305.com Member
Posts: 568
Joined: Tue Feb 02, 2010 7:11 pm
Location: Charlottesville, VA

Post by Dr. Frankenstein » Mon Jan 07, 2019 7:05 am

It seems I already asked this question in the Early section, too...I'm re-reading it now...

conbs
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Joined: Mon Mar 16, 2009 3:29 pm
Location: SW Idaho

Leaking petcock

Post by conbs » Mon Jan 14, 2019 10:27 pm

I haven't done this in a while but, I always had better luck using the cork packing. Also, it is really important to clean out the hole in the body so that the shaft on the fuel cock plate moves easily in it. If that shaft hangs up at all then it will either not go all the way in - and your petcock will leak because you won't be able to tighten the bowl completely - or the shaft will go in a pinch farther than you want and hang up - and, it will leak because there is a slight gap between the packing and the plate. The little "cross" spring on the plate is what puts the right pressure on everything (in theory) and keeps it from leaking.

Also, make sure your selector lever is smooth with no pitting.

I hope that helps.

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G-Man
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Re: Leaking petcock

Post by G-Man » Tue Jan 15, 2019 3:07 am

Great to have you back, Conbs... :-)

G

conbs wrote:I haven't done this in a while but, I always had better luck using the cork packing. Also, it is really important to clean out the hole in the body so that the shaft on the fuel cock plate moves easily in it. If that shaft hangs up at all then it will either not go all the way in - and your petcock will leak because you won't be able to tighten the bowl completely - or the shaft will go in a pinch farther than you want and hang up - and, it will leak because there is a slight gap between the packing and the plate. The little "cross" spring on the plate is what puts the right pressure on everything (in theory) and keeps it from leaking.

Also, make sure your selector lever is smooth with no pitting.

I hope that helps.
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