650 running very rich

[Gypsyjuggler]

Ok, I'm just speculating on this one. With the snow in Cleveland this bike isn't going anywhere for a few months.

I bought a 1982 GS650L from a friend last June. He said it was running ok but needed to have the carbs synced. Since I got it I see that I'm getting no better then 20 miles to the gallon. I had the carbs synced and it seems to be a little better, but not much. One occasion before the work was done, the bike kept stalling out (I'm assuming it was slightly flooded), after sitting for about 5 minutes I could fire it up and go a mile or so before doing it again. Luckily it wasn't a long trip home. I haven't had that problem since the work was done. I'm still coming up with blackend spark plugs after 2 tanks of gas. Not wet, just black.

I found out that the previous owner had a problem with the petcock on the bike and someone told him to replace it with a standard 2 setting valve, instead of a vacuum petcock the bike originally had. He replaced the valve just before I bought it.

I'm wondering if this new valve is part of the problem I'm having.

Anyone have any insight on this?

I'm not mechanically incline, so I plan on talking with a mechanic when the weather gets better and explain the symptoms and see what he says.

Gypsyjuggler
Parma Ohio

[Nicholaschase29]

I think that there needs to be back pressure where the vaccume line connects... But I could be totally wrong... Even if I am correct. I doubt that it is causing your bike to run rich on all 4 cylinders. You probobly have to lower your needles. If you run your bike wide open, does it still do this? or just between idle and wide open? If it does do it when you are running wide open, you probobly need smaller mains, and could probobly keep the needles where they are... but I am no expert and am still learning myself.

[chef1366]

Is the petcock a Suzuki part? If it's rigged just get a new one.
Make sure your vacuum line for the old stock petcock is plugged off. Do you have any aftermarket mods? Is the air filter old? How's the compression? Have you checked the valve clearence? Are you getting a good spark at the plug?
So many questions to answer and so much time till winter's over.

My dad lives in Cleveland. I still follow the Cavs, Browns and Indians.

[arveejay]

Sounds like 2 problems. 1. petcock over running carbs. 2. Float valves no shutting off fuel when bowls are full.

[brveagle]

Sounds like 2 problems. 1. petcock over running carbs. 2. Float valves no shutting off fuel when bowls are full.

exactly...

have you checked your oil at all? I bet it's full of gas..

Get a new petcock, overhaul your carb orings, and change your oil... in that order...

[Gypsyjuggler]

Well, Spring is starting to hit the Northeast Ohio area.

I've got the new petcock from Bike Bandit along with all the other little parts that I thought I might need to do the replacement. Also have a couple of oil filters on the way as well.

I'm reading the Clymer manual and part of me is thinking "That doesn't sound too difficult" and the other part of me is thinking "If I'm that confident about it, I'm in trouble"

I'll let you all know how it turns out.

Chef, what part of Cleveland did you come from? I grew up on the west side, W.130th and I-71 area.

[chef1366]

I'm from the Canton-Akron area. My dad just still resides in Ohio.

[Gypsyjuggler]

OK.... Now I really need some assistance.

OK, I ordered replacement petcock and such from BikeBandit.com and finally got the time to sit down and work on this problem.

I took off the fuel tank from the '82 650GL. I disconnected the main fuel line from the ON/OFF petcock that the PO had put on. (This was the only fuel line connection there)

With the new petcock in place, here is the confusing part. I have 3 connections: 1 on the gas gauge, circled in blue, 2 on the petcock itself, circled in red (I think the larger brass looking connection on the outboard side is for the main fuel line)



Now, on the bike itself, I have the main fuel line (circled in green) with an additional fuel filter the PO put on. From the top center of the engine there is a black tube that wasn't connected to anything. (circled in red) I think that was the vacuum line, although the size of the tubing is larger then will fit on either of the 2 connections on the fuel tank.


While I was taking these photos, I noticed something else. Looking from Cylinder 1 towards Cylinder 4 there is a capped item between cylinder 1 & 2(circled in red). Any idea what this is?


Thanks for any input you can give me.

Patrick

[rkubik]

crankcase breather

That big black tube you have circled in red is the crankcase breather. It goes from the top of the engine as you say and should go to a spigot on the top of the airbox. The hose is a bit short, which is why it's always popping off. Nothing to do with the fuel tap - function is like the PCV valve on a car, takes oily fumes and channels them for combustion.

The outlet on the gas gauge sensor - the thing you have circled in blue - is the fuel tank vent. It just connects to a long hose that goes down to the bottom of the bike. Again, not related to the fuel tap.

On the fuel tap, the smaller diameter tube is the vaccuum connection, which should connect to a fitting on the carb, I forget where but you'll see it - it's the same small diameter. And the bigger tube is the fuel outlet, which of course goes to the bigger diameter aluminum fuel inlet fitting on the carbs.

That fuel filter may be the cause of rich running. You really don't need it. There is a plastic gauze filter in the tank around the fuel pipes, and little metal gauze screens clipping on top of each needle valve in the carbs.

Between carbs 1-2 and 3-4 you'll see black plastic T fittings which are the carb bowl vents. They need to be open to atmosperic pressure, else the needle valves can't close and get.... flooding. Stock, there were long tubes on these, routed up overtop the airbox. A lot of people just leave them off, and that works fine too, except you may more dust. Or in my area, insects crawling into the carbs, dying and plugging things up.

[chef1366]

Blue on the first pic is as stated earlier. It is a vent that I have running down and it attaches to a hose clamp on my center stand.
Red in the first pic is the vacuum line for the petcock (small one) 1/4 inch vacuum line which connects to the cap you have circled in pic #3. The larger nipple circled in red in #1 pic is the fuel line. You should have a new screen in the new petcock so lose the inline fuel filter. (very important)
The red in pic #2 is the crankcase breather line. It should attach to a nipple on the top of your air box. Looks like you need to get a longer hose. If you don't attach this you will smell burning oil and it will drip oil.

[Gypsyjuggler]

Thanks for the input folks. I knew you guys would be able to help me out on this. I'll let you know how things turn out. I'm hoping to be up and running for next weekend. Still have an oil change to do and have the sissy bar attached.

Gypsyjuggler

[Gypsyjuggler]

Update

I was able to connect the fuel line, which took some doing to take the extra fuel filter off that the PO had put on. The breather tube was able to reach the airbox so that is connected. The vacuum tube went on pretty easy once I went back and picked up some clamps to hold the tube on. I didn't fuel up the bike to check for leaks because I ran out of sunlight.

My oil filters arrived on Monday so I will be ready to do the oil change in the next day or so.

After that I find I have another problem to work on: My front brake is not activating my brake light. I think I know were to look for this one.

[Gypsyjuggler]

Update on repairs

Alright gang, this is for anyone curious on how things turn out after a question has been posed on the board.

I pulled the bike out today into the sun so I could have a good look at things. After putting a small amount of fuel back into the tank, I put the petcock on "Prime" and watched the fuel start flowing down to the engine. Didn't see any major leaks on the connections I worked on. I did notice a small puddle (maybe a few drops of fuel) under where the fuel line connects to the engine. Not sure if that was from starting it up today or from when I drained the tank when I started this project.

The bike fired up after a few minutes and needed time to warm up. Needed to open the choke up this time. I don't remember needing to use the choke all last year when firing the bike up. The bike sounds better, and I can actually hear the vacuum line opening up the fuel valve when its at idle.

After warm up, checked for any more leaks. so far so good. Grabbed my helmet and took it around the block a few times. Bike feels good. Engine is slightly sluggish. Maybe this is from the stabil in the gas? Didn't have any problems with stalling, so its getting enough fuel to keep running. I hope that is a good sign. (Remember, I'm not a mechanic, I'm a printer so working with gasoline engines is a new thing for me.)

Next on the maintenance list: Change the oil.

After that, I have a scavenged sissy bar and rack that I picked up on Ebay last fall. I get to make that fit.

[tconroy]

Alright gang, this is for anyone curious on how things turn out after a question has been posed on the board.

I pulled the bike out today into the sun so I could have a good look at things. After putting a small amount of fuel back into the tank, I put the petcock on "Prime" and watched the fuel start flowing down to the engine. Didn't see any major leaks on the connections I worked on. I did notice a small puddle (maybe a few drops of fuel) under where the fuel line connects to the engine. Not sure if that was from starting it up today or from when I drained the tank when I started this project.

The bike fired up after a few minutes and needed time to warm up. Needed to open the choke up this time. I don't remember needing to use the choke all last year when firing the bike up. The bike sounds better, and I can actually hear the vacuum line opening up the fuel valve when its at idle.

After warm up, checked for any more leaks. so far so good. Grabbed my helmet and took it around the block a few times. Bike feels good. Engine is slightly sluggish. Maybe this is from the stabil in the gas? Didn't have any problems with stalling, so its getting enough fuel to keep running. I hope that is a good sign. (Remember, I'm not a mechanic, I'm a printer so working with gasoline engines is a new thing for me.)

Next on the maintenance list: Change the oil.

After that, I have a scavenged sissy bar and rack that I picked up on Ebay last fall. I get to make that fit.

We have something in common.I own an 83 650 and I am also a printer for the last 29 years!I have a clymers manual if you need some pics or anything just let me know and I will scan and send them to you.Do you have a clean and oiled air filter.Have you changed the plugs? You will need to sync the carbs also.Try using so seafoam in the gas.It will help tremndously!

[bradleymaynar]

The "Prime" setting is only for filling the carb float bowls. DO NOT use it when running the bike. Basically it bypasses the vacuum and uses gravity to fuel the carbs. Use it only to fill the carbs and turn the p/c back to the "On" setting once the bike is running. This is also the reason for changing the oil. If the bike sits with the p/c in the "prime" position, gas will continue to flow into the carbs resulting in gas seeping into the oil passed the cylinders. Once this occurs, you've essentially "thinned" your oil. This condition can cause major engine wear. Please change your oil and oil filter ASAP! I'd even go as far as to suggest you park the bike until you've completed these tasks. It's that crucial!

Brad bt