1978 gs1000e grey smoke coming ONLY from right exhaust

[Guest]

Ok this has happened a few times in the last couple of weeks , this morning it was a little extensive !!!
You have been driving the bike for about an hr , then your stuck in rush hour traffic , bumper to bumper , crawling at a snails pace !!
Then you right exhaust pipe begins to give off big plumes of greyish smoke ...
Please correct me if I am wrong .. would this be caused by a sticking fload needle or a float bowl that is not set up correctly ?

Smoke only comes out of the right pipe when this happens ! # 3 or 4 carb must be passing through gas to the exhaust , then causing it to smoke ?

Is there a way I can test to see if my float needle is infact stopping the gas from entering a full float bowl when at idle ?

Thx ahead of time for any suggestions

[lrgguy]

And the smoke only comes out of the right pipe !! So does this mean carb 3 or 4 has the issue ? One of the two ...

[lrgguy]

When this has happened , the only way I have been able to stop it from happening is to get into 3 rd or 4 th gear and crack the throttle lots .. im going to assume the volume of gas then traveling into either carb 3 or 4 releases the stuck float needle or bowl ???

[JTGS850GL]

That may tell you which cylinder is causing the smoking issue. Grey smoke could be from a stuck float. Are you sure it's not blue grey? When it's smoking, pull the plugs on 3 and 4 and see if either one is black or oil soaked.

There is a way to modify a float bowl screw to measure float level directly. You'll need an extra float bowl screw, but you simply drill a hole through the screw and epoxy in a tube. I think the screw is an M6 x .75 thread pitch. If you can find a bolt of the same size and pitch you can use that.

Connect the tube to some clear tubing and run it up the side of the carburetor. The fuel level in the tube will tell you what the fuel level in the float bowl is. If you have a leaking float valve the fuel level in the tube will rise above the preset float level.

[tkent02]

Check your petcock. Fuel can leak down the vacuum line into #3 if the diaphragm is leaking. It could be enough to cause smoke. It would smoke more in the stop and go traffic because there's more vacuum and less airflow through the engine. The vacuum line should be dry inside, if it's got any fuel in it that's your problem.

[lrgguy]

Check your petcock. Fuel can leak down the vacuum line into #3 if the diaphragm is leaking. It could be enough to cause smoke. It would smoke more in the stop and go traffic because there's more vacuum and less airflow through the engine. The vacuum line should be dry inside, if it's got any fuel in it that's your problem.

Just checked .. very small amount of fuel in vacume line !! You nailed it ...

Is there something I can do to the petcock to do a temporary fix ?

[tkent02]

Temporary use only, take the vacuum line off, plug it so no air is allowed into the carburetor.

Use PRI to ride, turn it to on when you shut it off. DO NOT leave it on PRI when the engine isn't running. On is really off when there's no vacuum, so fuel won't fill the carburetors when it's parked. It may drip fuel out the vacuum port on the petcock all the time, depending on how bad it is. If it does, block it.

Get a new petcock, it's past time.

[lrgguy]

Temporary use only, take the vacuum line off, plug it so no air is allowed into the carburetor.

Use PRI to ride, turn it to on when you shut it off. DO NOT leave it on PRI when the engine isn't running. On is really off when there's no vacuum, so fuel won't fill the carburetors when it's parked. It may drip fuel out the vacuum port on the petcock all the time, depending on how bad it is. If it does, block it.

Get a new petcock, it's past time.

And by doing this , on the prime position , sitting in traffic I wont flood anything out ? Getting out of down town Toronto can be very slow in spots ...

I guess if anything floods out then it would be anouther problem witha sticking float bowl or float needle ?

[lrgguy]

And is there a petcock that is being used these days that doesnt cost $300.00 new ? So I have been told is to not waist my time with petcock rebuild kits ?

[tkent02]

And by doing this , on the prime position , sitting in traffic I wont flood anything out ? Getting out of down town Toronto can be very slow in spots ...

I guess if anything floods out then it would be anouther problem witha sticking float bowl or float needle ?

Hopefully everything else is working correctly.

[lrgguy]

Hopefully everything else is working correctly.

Thank you .. and I hope everything works correctly too !! Hahaha

[lrgguy]

Hopefully everything else is working correctly.

Will a petcock off a1983 gs 650 line up with fastening holes on a 78 gs 1000 ?
Cuzz the petcock on my 650 is fine and was replaced last yr

[JTGS850GL]

Wow! What is it with the 78,79 1000 petcock that makes it so darn expensive? I looked and couldn't fine a complete assembly alternative to OEM or the kits.

[lrgguy]

Wow! What is it with the 78,79 1000 petcock that makes it so darn expensive? I looked and couldn't fine a complete assembly alternative to OEM or the kits.

I see them on ebay ranging from $52.00 - $150.00
Called my supplier here and a oem suzuki petcock is almost $300 ...
Myself I have never purchased on line or of ebay I know everyone does , but I simply dont trust looking at a picture and forking out $$$ and hope its in working condition oris the right part when it arrives ...
Guess im stuck in the 80's

[lrgguy]

Wow! What is it with the 78,79 1000 petcock that makes it so darn expensive? I looked and couldn't fine a complete assembly alternative to OEM or the kits.

My other used parts guy here in toronto has a used petcock thats probably worse off then the one I have for $150 .. lmao or a rebuild kit on the shelf for $32.00 and ill bet its been there for 10 or more yrs and it is all dried out ... hahaha