Topic: Petcock leak (drip) in off position

[thomellis]

I've searched around, and tried a few things but I just can't seem to get this little bugger to stop leaking.  There are no external leaks, just a slow drip which eventually leads to one of my bowls overflowing if I leave the bike sitting overnight.

I just replaced the fiber washers to see if that might be the culprit, but no dice.  The bike is a '72 cb750, but I don't think it is the stock tank.  Everything works fine in the On or Reserve position, but when I switch it to Off, it leaks drip by drip.

Anyone have any ideas?  Thanks for any advice/help you can provide.

[dhall57]

My 750KO had the same type petcock leak. Took apart and cleaned and replaced all seals,o-rings,etc. with all OEM Honda parts and has not leak since.

[ekpent]

From other posts here the 2 orange-red fiber looking seal washers that go under the two petcock mounting screws are critical and may be the cause of the leak if they are bad or missing.

[Tugboat]

My guess is it's the 4-holed rubber "washer" behind the on/off/res lever.

[Duke McDukiedook]

My 750KO had the same type petcock leak. Took apart and cleaned and replaced all seals,o-rings,etc. with all OEM Honda parts and has not leak since.

+1.

[bryanj]

Did you usw generic "Fibre" washers instead of honda parts ----- If so thats your problem as they will be thw wrong size and too thin

[thomellis]

Thanks to everyone for the replies.  I did use generic fiber washers from the auto-parts store.  They seemed to fit really snug (I basically had to screw them onto the bolts), but I'm sure they weren't an exact match.  I thought maybe they might just need a bit of time to seat properly.

Looks like I may just have to end up rebuilding the petcock.  Looks like the parts are only about $10 total + s/h, so it's probably not a bad idea anyways.  I fixed the carb so it no longer overflows at least, so this is really just more of an annoyance when I have to take it off the bike.

Thanks again!

[ekpent]

Make sure all the drains for the carbs are working well so if the petcock does continue leaking the gas will end up on your floor and not have the possibility of getting into the engine and contaminating the oil.