Petcock Replacement - YEAH!

[motomonkey]

Ok, so I've read some stuff on this forum and I am voting that I REPLACE the petcock instead of rebuilding. When the tank is full I have a nice, smelly gas leak, carbs are wet with fuel. So, please correct me if I'm wrong:

I am replacing the petcock because A. I can't easily move the little lever from RES to ON, actually, I can't move it without some type of tool and B. because there is a gas leak when I fill the tank to the top that is coming out by the carbs.

I am looking for a petcock for my 1982 GS650G and since it was made in 1982 it will say GS650GZ? I think.

What else? I think that's it.

Thanks for your helps!

Candice

 

[Larry D]

I agree. Replace the petcock. Replace the fuel and vacuum lines too. Have you cleaned/dipped and rebuilt the carbs with new orings ?

 

[rphillips]

This has been talked about forever. It seems to be about a 50/50, around here, if it's better to rebuild or replace the petcock. I'm on the rebuild side, but I've not had a problel with rebuild as others have had. Rebuild, appx. $20, new, appx. $60, you spend $20, to try to save $40. If it doesn't work & you hafta buy a new one anyhow, you wasted the $20. It's just another one of the worldly gambles of day to day life. Let us know what works out for you. Just my opinion

 

[motomonkey]

Yes, I've read the many back and forths of rebuild vs replace. I am replacing, I'd rather just replace it and be done with it. I was just looking for validation that my thoughts are on the right track since I have never worked on any type of machinery in my life.

Candice

 

[motomonkey]

I agree. Replace the petcock. Replace the fuel and vacuum lines too. Have you cleaned/dipped and rebuilt the carbs with new orings ?

Ha ha, uhhhhh - no. I will keep all that in mind though. Let's see if I can handle this petcock replacement first. Although I have to say, it just seems like a screw the old one off and screw the new one on, that's not so bad.

Candice

 

[Larry D]

Ha ha, uhhhhh - no. I will keep all that in mind though. Let's see if I can handle this petcock replacement first. Although I have to say, it just seems like a screw the old one off and screw the new one on, that's not so bad.

Candice

You are correct changing the petcock is easy. I think there is a gasket under there too.

Unscrew the oil filler cap and take a good whiff, I'm guessing some gas has gotten into the crankcase. DO NOT start the engine !! The oil and filter needs changed. Run the bike for 100-200 miles and change it all again.

Your petcock has certainly failed....but....so has the needle valves seats in the carbs. You MUST replace those orings as well or you're going to have the same problem all over again.

There are two lines of defense from overflowing carbs...the petcock and the needle valves seats. Both must be operating properly.

Have you at least read the carb rebuild series ? It's not that difficult to do a rebuild on the carbs......really.....honest...I'm not kidding.

 

[spyug]

Have you at least read the carb rebuild series ? It's not that difficult to do a rebuild on the carbs......really.....honest...I'm not kidding.

He does not lie. Doing the carbs is one of the biggest confidence builders in bike wrenching for newbies. The tutorials are easy to follow and hold your hand the whole way. The secret to it is to be organized and thorough. Take your time and don't rush. The first set might take a week but the next time, you'll have it down to hours.

Put it on your list of "to-dos" for 2010.

You can thank us later.

Cheers,
Spyug

 

[JTsGS650]

Also keep in mind that there is an oring gasket which seals the petcock to the underside of the fuel tank and two rubber washers/gaskets around the bolts which secure the petcock. I suggest replacing these as well, since they are cheap. See the 'fiche below (numbers 2 and 4, respectively).

 

[Steve]

There are two lines of defense from overflowing carbs...the petcock and the needle valves seats. Both must be operating properly.

Very true, but ... (seems there's always a big butt in there, somewhere :-\\\)
Either one of those systems will hold back fuel if it is working properly. Having both of them is just insurance.
The problem is that you don't know that you have a problem until they BOTH fail.

.

 

[motomonkey]

Also keep in mind that there is an oring gasket which seals the petcock to the underside of the fuel tank and two rubber washers/gaskets around the bolts which secure the petcock. I suggest replacing these as well, since they are cheap. See the 'fiche below (numbers 2 and 4, respectively).

If I buy a new petcock does 2 and 4 come with it? I was assuming they did include those.

Candice

 

[spyug]

Unlikely. When you see individual parts numbered it is a good indication they are sold seperately. Make sure you can confirm that. On the upside, though, if the o-ring is not split it can likely be reused. Get some silicone spray and "massage" it in with your fingers to rejuvenate it. Better yet just buy one even if it is $5 or more (which it might be).

Keep us informed of how it goes.

Cheers,
spyug

 

[motomonkey]

Unlikely. When you see individual parts numbered it is a good indication they are sold seperately. Make sure you can confirm that. On the upside, though, if the o-ring is not split it can likely be reused.

Thanks! That o-ring will have to be replaced for sure. Noticed you are from Hamilton, I am originally from Sault Ste. Marie.

Candice

 

[spyug]

Haven't been to the Sault yet but I hear it is pretty country and there's some good riding thereabouts. So you live in Joliet the home of "Joliet" Jake Blues ( Dan Ackroyd) of "Blues Brothers" fame.....anywhere near the 'big house"?

I take it you haven't been long into bikes and I know they seem somewhat intimidating to work on but really are straight forward if you can follow a manual and learn to read the odd schematic.

With the old iron, maintenace is the key as you already know. These Zuks are rock solid dependable in the mechanicals but like every other old bike, they can suffer from electrical gremlins and you should pay attention to these as this is where you can be left stranded some day.

The electricals are prone to a couple of issues that can be a killer but easily prevented. Most notably charging or rather non charging. This can be as a result of a bad stator ( quite common) bad rectifier/regulator ( also common) or more likely bad or corroded connectors and weak or missing grounds. You really need to know the health of your charging system and for this you will need a few tools. Primarily a digital multi-meter and a circuit tester. Both available at good auto stores and usually no more than $20 or $30 combined. I would also recommend you get a voltage meter to wire into your bikes system to monitor things as you ride along. Nothing worse than taking a two hour ride away from home and stop for coffe only to not be able to start the bike when you want to leave. A voltage meter will give your peace of mind or early warning of a potential failure.

Electricals can confound people but are not difficult if you apply common sense ( and refer to a good book, I strongly recommend Tracy Martin's Motorcycle Electrical Systems- Troubleshooting and Repair, about $25 all good bookstores).

Have a look at the tutorials on the Stator papers for background and check your battery and charging with you're multimeter. There are also lots of threads on the subject. Also clean up any gungy or corroded connectors starting at the battery terminals and make your way up to the headlight bucket. Corroded connectors cause resistance in circuits and full voltage is not going to flow, this then causes things like weak headlights, hard starting, slow flashing signals and the aforementioned lack of proper charging.

Again it seems like a lot and it would be if you went at it whole hog but do a bit at a time and soon you'll have it all covered, the bike will be more reliable and you're self esteem will soar.

Keep us informed of how things go.

Cheers from the Hammer,
Spyug

 

[JTsGS650]

If I buy a new petcock does 2 and 4 come with it? I was assuming they did include those.

Candice

No they don't. It is cheap insurance to buy new and replace the old ones though.