Gas tank petcock and ticking sound in gas tank?

[roy826]

Rebuilt the petcock with a K&L kit everything went well no issues. Only now when bike is at idle I hear a ticking sound from the gas tank. Removed tank and ran bike with out it and no ticking sound. Reinstalled tank and put a screwdriver to petcock and at my ear I hear the source of the ticking. Sounds like the diaphragm working from the vaccum as it should but why the noise? Old diaphragm was bad and leaking so no noise then. Strange I do not recall this 20+ years ago on this bike.

[Eli69]

I've had that happen. Became more noticeable as the tank got closer to empty. I don't remember for sure but I don't think it was a real problem. I was just glad the noise wasn't coming from the motor.

It was a 81 or 82 gs650l.

Just make sure you're not getting gas leaking into the vacuum line.

[roy826]

I've had that happen. Became more noticeable as the tank got closer to empty. I don't remember for sure but I don't think it was a real problem. I was just glad the noise wasn't coming from the motor.

It was a 81 or 82 gs650l.

Just make sure you're not getting gas leaking into the vacuum line.

This is a 82 GS1000S so same fuel petcock design as yours. Yea I was concerned it was the new coils I just installed which spark and close to fuel not a good thing. At least it wasn't the new coils arcing somewhere. So far no fuel on vacumn side and the thing appears to be working fine in all positions of the lever. I have not kept much gas in it due to the on going work I have been doing to it so it may disappear with a full tank. It has maybe 1.5 gal in it.

[Cipher]

I cant believe you have such good hearing. To make sure its not the new coil clearance temporarily lay a wash cloth or similar across them. if they are rubbing this will dampen any tick.

Is it possible that the fuel level flot is the source?

Ive never heard a petcock tick. why would it? under engine vacuum it draws open and stays that way till shutdown.

[roy826]

I cant believe you have such good hearing. To make sure its not the new coil clearance temporarily lay a wash cloth or similar across them. if they are rubbing this will dampen any tick.

Is it possible that the fuel level flot is the source?

Ive never heard a petcock tick. why would it? under engine vacuum it draws open and stays that way till shutdown.

It is 100% not the coils absolutely no sound when tank is removed or anything visible in a totally dark room with headlight covered and no spark or arcing anywhere. Coils were brand new OEM Suzuki units. It is certainly the petcock diaphragm piston laboring at idle. After it is revved and valve is held open no noise. The screwdriver trick to the ear on the petcock confirms this. I do not know why or how but the bike is 40 years old and strange things are bound to happen at this age. I think at idle it is just not pulling enough vacuum to keep the new diaphragm fully open or maybe the old stock spring in there is really good and the K&L diaphragm is junk rubber. At this point I am not going to worry to much more about it. The petcock is working as it should minus the ticking noise which is very faint and I hear it because I have very good hearing unlike my eye sight. This bike does not have a fuel level gauge.

[Brendan W]

Could you have a vacuum leak somewhere on the vac hose?
Something as simple a split at the petcock end?

[bwringer]

This may be the first time I've heard of a rebuild kit actually working, although it sounds like it's probably not working correctly.

I've also never heard of a petcock ticking, although I've also never really listened for that.

You can certainly feel vacuum pulses at idle, but overall the petcock should remain open whenever the bike is running instead of whacking back and forth. It should take very, very little vacuum to open the petcock.

[roy826]

Could you have a vacuum leak somewhere on the vac hose?
Something as simple a split at the petcock end?

No vacuum leaks bike runs and idles fine

[roy826]

This may be the first time I've heard of a rebuild kit actually working, although it sounds like it's probably not working correctly.

I've also never heard of a petcock ticking, although I've also never really listened for that.

You can certainly feel vacuum pulses at idle, but overall the petcock should remain open whenever the bike is running instead of whacking back and forth. It should take very, very little vacuum to open the petcock.

Does not take much vacuum to pull it open I have tested it and hear it working. In fact tested all positions of the valve and it all works as should. Noise is coming from the petcock and echoing through the hollow tank. I can lift tank with hoses attached and it running and still hear the ticking noise. Remove the tank and no noise anywhere. As soon as the tank is reconnected the ticking noise reappears. Only at idle anything above that no noise.

[Eli69]

Wish I could remember exactly what happened with mine. I know it was a good way to tell when I was getting close to needing gas. I think that I ended up having to fix it though. Darn I can't remember. I guess my point is that you're not the first to experience this.

[roy826]

Wish I could remember exactly what happened with mine. I know it was a good way to tell when I was getting close to needing gas. I think that I ended up having to fix it though. Darn I can't remember. I guess my point is that you're not the first to experience this.

Buy a new petcock from Suzuki? Dealer already quoted me $57 for one before I decided to go the K&L rebuild route which was $24. If this is all it does and continues to work properly which it is right now i can live with the ticking noise. Just was initially concerned about a fire hazard until I nailed it down as a mechanical noise not a spark.

[Eli69]

I did find new petcocks on ebay and amazon. I've got one on a bike right now. It works but is real hard to turn the lever.

[roy826]

I did find new petcocks on ebay and amazon. I've got one on a bike right now. It works but is real hard to turn the lever.

Mine was hard to turn before the rebuild kit was installed now the lever turns very easy. New kit oring was added to the lever.

[salty_monk]

Most likely something vibrating against the tank in the tunnel. This can be the coils if the spacers aren't fitted right or they are aftermarket....

[roy826]

Most likely something vibrating against the tank in the tunnel. This can be the coils if the spacers aren't fitted right or they are aftermarket....

Coils are new OEM suzuki which came with the spacers already on them. The new coils came with the new plug wires already attached as well just cut to fit and screw on your plug caps. All that was needed from me was the stock 10 mm bolts to attach them to the frame mounts. Nothing rattling I checked and rechecked the wiring in that location on the Frame backbone rails.