Petcock leaking after rebuild..

No eBay APP ID and/or Cert ID defined in Kunena configurationUsed this kit;



..to rebuild my petcock just now, and it drips out of the fuel outlet.

Wondering if anyone has experience with these kits being junk. I did polish the o-ring seat with steel wool before re-assembling, and nothing looked out of the ordinary.

Any petcock rebuild tips, tricks, advice.. anything really is appreciated.

I also have a leaky petcock on my 82 KZ750H and was looking for a rebuild kit. I don't have anything to add to your thread but I'm curious to find out how it turns out for you. Mine drips from the fuel outlet when in on/res position with no vacuum applied.

Did that kit include the petcock to tank o-ring?

Forget vacuum shut-offs. Find a manual shutoff that fits. Plenty of 'em on ebay. Just remember to shut em off at the end of the trip.

Took it apart and had a look over everything to check for o-ring/diaphragm rips and all that, put it back together and it still dripped. So I used a hand vacuum pump to cycle everything a few times and right now... it's not leaking. Hopefully that has seated everything nice and I'm good to go.

The kit came with all of the rubber parts for the petcock, the tank o-ring is pictured there and comes as just an o-ring that you have to shape to the groove in the petcock. I like that it's made in Japan, and seems to be of a high quality.

I have the tank off and set up on the lip of a dry pan, will update tomorrow.

Just shelled out for the rebuild kit, would like to get some use out of it.

It's years since I had to do anything with my petcock but I seem to remember that I had to take the spring and stretch it a bit so that gas stopped when the vacuum was off. That was probably 10 years ago and it has been fine since.
I actually like the vacuum petcock. I would put manual petcocks are in the same league as old style points ignitions

JR wrote: It's years since I had to do anything with my petcock but I seem to remember that I had to take the spring and stretch it a bit so that gas stopped when the vacuum was off. That was probably 10 years ago and it has been fine since.
I actually like the vacuum petcock. I would put manual petcocks are in the same league as old style points ignitions

Me too! I have points ignition and a manual petcock - I've had no problems with either one. Ed

JR, that right there is some good thinking on the spring, and I am feeling like a bit of a dunce for not getting there myself.

All of this stuff works the way it's supposed too when well maintained. If my bike had points and a manual petcock when I got it; I'd keep it that way.

650ed wrote:

JR wrote: It's years since I had to do anything with my petcock but I seem to remember that I had to take the spring and stretch it a bit so that gas stopped when the vacuum was off. That was probably 10 years ago and it has been fine since.
I actually like the vacuum petcock. I would put manual petcocks are in the same league as old style points ignitions

Me too! I have points ignition and a manual petcock - I've had no problems with either one. Ed

Ha ha
Good one Ed
Touche :laugh:

Try pulling the spring apart and reinstalling it. There is also a backing plate that should be bent that sits next to the on off res lever. If you slightly bend the plate back into its original position it should stop the leak.

nickleo373 wrote: Try pulling the spring apart and reinstalling it. There is also a backing plate that should be bent that sits next to the on off res lever. If you slightly bend the plate back into its original position it should stop the leak.

Is there a diagram of this somewhere?... if it needs to be bent and I've never had it apart before how will I know what it's original position is?

Been a couple-ish days and the valve is dry. Thanks for the pointers.