Author Topic: Petcock Assembly Inquiry  (Read 839 times)

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Offline brendanpk

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Petcock Assembly Inquiry
« on: March 08, 2010, 09:36:49 AM »
hello all. i have a 1973 cb350 twin. this winter season i cleaned the tank and after putting the petcock back on it was leaking from the lever. yesterday i bought a new gasket that wasn't specifically marked for honda, but it fit perfectly and the holes matched up correctly, and still it leaked with that. so i have a two part question.

1. does the gasket have to soak in gas and expand to seal properly (i know some rubber expands in gas)?

2. does the warped, circular metal retaining ring go under the lever (between the lever and gasket) or on top of the lever (in between the lever and metal plate with stop/run/reserve)?

thanks for any help and feedback possible!

Offline Gorms

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Re: Petcock Assembly Inquiry
« Reply #1 on: March 08, 2010, 09:55:56 AM »
I dont think the rubber seal has to be soaked in gas to do its job an if I remember correctly, the warped metal ring goes under on top the lever.  I think.....
« Last Edit: March 08, 2010, 09:57:41 AM by Gorms »

wdhewson

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Re: Petcock Assembly Inquiry
« Reply #2 on: March 08, 2010, 10:16:45 AM »
Hi:

Not only do the holes have to line up, but the thickness of the seal needs to be correct for the proper compression of the seal.  The wavy washer is a spring which goes atop the lever circle and presses the lever into the seal.  If you have proper shims on the spring washer, you could increase that compression.

The sealing surfaces of the lever and backside of the petcock need to be clean and not corroded.

Any leak and gasoline will find it.  Proper nitrile rubber shouldn't swell or shrink any more than an imperceptible 5% or so.

Good luck.  Don

Offline brendanpk

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Re: Petcock Assembly Inquiry
« Reply #3 on: March 08, 2010, 10:28:37 AM »
both of those answers help greatly... thanks for the feedback guys. hopefully i'll be up and riding today!!

Offline TwoTired

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Re: Petcock Assembly Inquiry
« Reply #4 on: March 08, 2010, 10:32:28 AM »
1. does the gasket have to soak in gas and expand to seal properly (i know some rubber expands in gas)?
Not if you have the correct gasket.

2. does the warped, circular metal retaining ring go under the lever (between the lever and gasket) or on top of the lever (in between the lever and metal plate with stop/run/reserve)?

in between the lever and metal plate with stop/run/reserve
Lloyd... (SOHC4 #11 Original Mail List)
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