Leaking Petcock. Again.

shade

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Now that I've got the bike running again the petcock is leaking. I ordered a rebuild kit http://www.ebay.com/itm/350957109557?_trksid=p2057872.m2749.l2649&ssPageName=STRK:MEBIDX:IT.

I followed the instructions here http://www.xs650.com/forum/showthread.php?t=20662
but when I installed the rebuilt Petcock it is still leaking.

A bit of history: It's not the original petcock. When I first had a leaking problem I ordered a new petcock from Mikes that leaked right out of the box and was generally useless. I then ordered a used Petcock off of Ebay and it has been working fine until now.
 
A bit of history: It's not the original petcock. - - - I ordered a used Petcock off of Ebay and it has been working fine until now.

Hi shade,
you rebuilt the used petcock with that kit exactly like the link said and it still leaks?
Where from?
If it's the vacuum on/off side, stretch the diaphragm spring a bit.
If it's the gas tap side, very carefully re-bend the wavy spring to seat the valve harder.
 
It seems to be leaking from the square plastic piece. I placed a washer in it to give the spring a little more push, but it's still leaking. I'm just wondering if it's the right rebuild kit etc., before I take it apart again.
Thanks
 
Followed the steps again, and paid special attention to sanding and polishing. Still leaking. Thinking maybe the spring is bad?
Before I put it back on the bike i poured some carb cleaner through it and it went right through without leaking but when I put it on the bike it is leaking a lot. Way worse than when I started.
 
Followed the steps AGAIN. This time it seems to be sealing on the main body of the petcock but now gas is pouring out of the "drain screw." Is there something to use to better seal that drain screw?
Thanks
 
Hi shade,
Gary's petcock rebuild string shows the drain screw as a crosspoint-headed item sealed with a flat plastic washer.
So long as the drain screw itself hasn't been swapped for one that's too long so it bottoms out before the washer goes tight, the washer seat and the screwhead's underside are clean, smooth and square to the bore and the washer is complete; gas may drip out if the screw ain't tightened enough but there's no way gas should "pour out".
 
Hi shade,
Gary's petcock rebuild string shows the drain screw as a crosspoint-headed item sealed with a flat plastic washer.
So long as the drain screw itself hasn't been swapped for one that's too long so it bottoms out before the washer goes tight, the washer seat and the screwhead's underside are clean, smooth and square to the bore and the washer is complete; gas may drip out if the screw ain't tightened enough but there's no way gas should "pour out".

The drain screw on mine has a thin washer but not a plastic washer, I dug out my old petcock to get the spring out of it and it has the same thin washer. I guess I will see if I can order a plastic washer like Gary's.
Thanks
 
OK I was wrong about the plastic washer it was in there.

I took a look at the old original petcock and realized it is salvageable. I went through the steps again and had it sanded, polished and cleaned up until it was shiny and smooth. Put it all back together and.... it leaks.
I understand that I ask a lot of stupid questions, and it usually takes me 2 or 3 times to get something right, but I have done this over and over again diligently and it still leaks.
Any suggestions are appreciated.

I will be away from the bike for a few days.

Thanks
 
Hi shade,
perhaps it's time to cut your losses and buy a new gas tap?

I know what you mean, but last time I bought from Mikes it leaked from the start. Any suggestions on where to get a good one? I like he idea of a vacuum petcock so I don't forget to shut it off. Think I need to order a new master cylinder as well, and it's almost time to repaint the tank.
 
A couple of random ideas.

If you still have the original parts, compare the length of the small shaft of the diaphragm. I have found some that weren't long enough..........

Some of the 4 hole seals in aftermarket kits leak out of the box. Seems like some aren't thick enough.

Dirt in the gas tank will make a fresh petcock leak about instantly.

I feel your pain, I usually have no problem stopping petcock leaks. But the bone stock 79 I was working on this summer filled the crank with gas three times.

:banghead::mad::banghead:
 
A couple of random ideas.

If you still have the original parts, compare the length of the small shaft of the diaphragm. I have found some that weren't long enough..........

Some of the 4 hole seals in aftermarket kits leak out of the box. Seems like some aren't thick enough.

Dirt in the gas tank will make a fresh petcock leak about instantly.

I feel your pain, I usually have no problem stopping petcock leaks. But the bone stock 79 I was working on this summer filled the crank with gas three times.

:banghead::mad::banghead:

I compared the two quickly but I will measure them next time. The gas tank is pretty clean, but there could always be something in there. I don't want to give up so when I get back to the bike I will have another go at it. I will look for a replacement seal so I don't have to pay for an entire rebuild kit yet again.
Thanks a lot by the way for posting the petcock rebuild procedure, it's been very helpful.
 
I know what you mean, but last time I bought from Mikes it leaked from the start. Any suggestions on where to get a good one? I like he idea of a vacuum petcock so I don't forget to shut it off. Think I need to order a new master cylinder as well, and it's almost time to repaint the tank.

Hi shade,
you could try placing your next order with 650 Central?
They'll know the correct diameter for a replacement M/C too.
My usual caveat about painting:- Fer Chrissake wear a good breathing mask.
If them solvents don't rip yer lungs out first they'll linger on to destroy yer liver.
 
I have found the quality of the original parts to be excellent compared to the replacement china Stuff.
I went back to the stock petcock after trying a on/off replacement from mikes.
as Gary said " If you still have the original parts, compare the length of the small shaft of the diaphragm."
My rebuild leaked, I found that shaft was slightly shorter and the oring was not seating After some tricky bending of the aluminum backing plate to make the shaft a bit longer is been working great.
 
It amazes me when so much time is wasted on such sundry items these parts were not made to last when mine goes, I will buy pingel petcocks, job done!
 
I went thru something like this with my cop bike. I took the petcock apart and put it together a half a dozen times. It turns out the diaphragm, which was a brand new factory item, had a small tear in it. You really had to examine it closely to see it.
Just a suggestion...
 
It amazes me when so much time is wasted on such sundry items these parts were not made to last when mine goes, I will buy pingel petcocks, job done!

It might sound crazy, but I enjoy learning about the bike and working on the best I can (with the help of the members of this forum...)
Thanks for the Pingle Petcock suggestion, it looks like I would have to buy an adapter and then put the screw holes in for the xs650 tank mount?
 
I went thru something like this with my cop bike. I took the petcock apart and put it together a half a dozen times. It turns out the diaphragm, which was a brand new factory item, had a small tear in it. You really had to examine it closely to see it.
Just a suggestion...

Thanks I will go over the diaphragm closely. Were you able to repair the diaphragm or replace it?
 
I have found the quality of the original parts to be excellent compared to the replacement china Stuff.
I went back to the stock petcock after trying a on/off replacement from mikes.
as Gary said " If you still have the original parts, compare the length of the small shaft of the diaphragm."
My rebuild leaked, I found that shaft was slightly shorter and the oring was not seating After some tricky bending of the aluminum backing plate to make the shaft a bit longer is been working great.

Great suggestion, thanks!
 
It might sound crazy, but I enjoy learning about the bike and working on the best I can (with the help of the members of this forum...)
Thanks for the Pingle Petcock suggestion, it looks like I would have to buy an adapter and then put the screw holes in for the xs650 tank mount?

The adapter plates come pre drilled for the spacing needed to mount to the tank. You just need to measure the stock spacing for your tank and order.
There are two different spacings that I'm familiar with.....I'm thinking the '83 is 44mm, hole to hole.
Confirm that, if you decide to go that route.

Quick search on Amazon brought this up http://www.amazon.com/Pingel-Power-...8-1&keywords=Motorcycle+petcock+adapter+plate
Note that the tank opening may have to be increased just a tad to accept the petcock filter into the tank.
 
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