Float level clarification.

[suzukizone]

RE: GS850G '81

Trying to clarify the concept of measuring the float level properly. I was taught to tilt the carb(s) so as to slowly bring the float tang into contact with the pin of the float needle and to continue tilting it until the "slack" in the pin is gone and the pin begins to press against the spring inside of the needle mechanism.

I have also been told to adjust to the point at which the tang first contacts the needle's pin and not take up the slack.

In the pictures in the carb section it appears the carbs are completely upside down with the floats resting fully against the needles' pins.

Which is correct? (if any?????) Hope I have explained it clearly enough.

Thank you so much.

DH

[tkent02]

Your way is correct, use the angle that just touches the valve.

[hikermikem]

I have also been told to adjust to the point at which the tang first contacts the needle's pin and not take up the slack.

This is how i do it...

[suzukizone]

Float level clarification.

Thanks guys, did it that way but was super extra fussy about getting it right to the mm & even checked both floats on each.

Appreciate the quick response.

Still trying to figure out why bike is running so rich, especially # 1 & 4.

All jets are spec.

Oh well back to the workshed.
DH

[nert]

running rich, 1+4?
1+4 share the same ignition coil?
1+4 are outside cylinders and therefore run a little cooler?
Did you sync the carbs?
AND if you want to be fussy, set the bike level on left to right on the center stand, shim as neeeded to obtain level. And adjust the fuel floats to give the correct fuel LEVEL as described in the service book. You could have the floats spot on with a ruler and easily have a low fuel level on one carb and high fuel level on another carb many mm apart.
Also, make sure the fuel enrichment valves have good seals and are closing completly.

[suzukizone]

Float level clarification.

Thanks Nert, very frustrating as it runs great as soon as I get away from idle.

Recently replaced pistons, rings, etc also valve springs and had one bad (#2 EX) valve replaced and seat redone, all other valves lapped slightly. Checked & no leakage from valves. Carbs are checked all jets stock, were synched. My mixture screws, from 1 to 4 are set at;

3/4, 1.0, 1.0, 3/4 out.

The little rubber seals on them were replaced not to long ago., Also the seals between manifold & engine though prob there would cause lean not rich, no?


Rechecked & tweaked float levels to 22.4mm, they were so close before but got them to perfection.

Still getting black soot around metal base of plugs & electrode end is dark brown.
BTW this rich issue was there before the engine rebuild but leakdown test showed rings & valves were worn out as was confirmed when head pulled.

I just got a carb bowl drain bolt & will be rigging up a tube to check float bowl level from outside. Where should the level come to,....the seam between float bowl & carb body???

Anyway thanks for looking in on me.

DH

[nert]

now we need more info.
You say its rich, but runs great once past idle. How do you know its rich? when and how are you checking the plugs.

Do you have "BS" constant velocity type carbs? Big dome on top? or "VM"?

I believe mixture screws (on the BS) should be closer to 1 1/4 to 1 1/2 turns out.
Turn out adds more air, more lean. Less turns is actually richer.

The fuel level adjustment, although time consuming and messy to set, is very accurate.
BS, 5.0mm or .20 inch below the carb body flange.

The seal, manifold to engine, if leaking will cause lean. However, i am asking about the choke seals, as they can be causing lean.

I would find brown spark plugs insulators favorable to White insulators. Tan is very nice.

WHAT is the actual symptom(s) you are experiencing that prompted this thread? ( i don't think you stated) What exactly is the "rich issue"?
Does it run better with partial choke, from idle?
Info as to the problem you are experiencing might be a direction than asking about a rich mixture.

Is the rest of the "engine" stock? Meaning air filter, and exhaust, and ignition?

[suzukizone]

Float level clarification.

now we need more info.
You say its rich, but runs great once past idle. How do you know its rich? when and how are you checking the plugs.

Once warm bike stalls on idle or coming to a stop shifting to neutral. If I keep idle 1300-1500 I usually cheat this but not always.

Electrode tip very dark brown, black soot on the plug body(metal) and porcelin is quite dark too. Have not done the rpm plug chop as described. Sorry.



Do you have "BS" constant velocity type carbs? Big dome on top? or "VM"?

BS, CV diaphragm carbs.

I believe mixture screws (on the BS) should be closer to 1 1/4 to 1 1/2 turns out.
Turn out adds more air, more lean. Less turns is actually richer. That is why I have then cranked in so far.

Agree where setting should be but turn out richens and turn in leans. These are fuel mixture screws not air screws.

The fuel level adjustment, although time consuming and messy to set, is very accurate.
BS, 5.0mm or .20 inch below the carb body flange.

Getting ready to make a tube tool to measure this.

The seal, manifold to engine, if leaking will cause lean. However, i am asking about the choke seals, as they can be causing lean. Replaced the manifold seals and choke plungers have built in seals, part no available from Suzuki or K&L, possibly from SUDCO, have to research.

I would find brown spark plugs insulators favorable to White insulators. Tan is very nice.

Not as dark as these, I'm in Hershey-Land here.

WHAT is the actual symptom(s) you are experiencing that prompted this thread? What exactly is the "rich issue"?

Both before & after top end rebuild began to experience the above noted "rich" issue.
Does it run better with partial choke, from idle?

No that would be a lean prob with idle/low end circuits. I deal with this issue at the shop daily. Nothing lean right now with Roadkill. I get off idle within 20-30 seconds. Rides off fine. Problem starts to show up in 4-5 miles and just with idle tho very excessive fuel consumption (1/2 what it used to be) is also troubling. Used to push 50 mpg an open road.


Is the rest of the "engine" stock? Meaning air filter, and exhaust, and ignition?

Air filter is K&N stock replacement type. All else stock. Windjammer with lowers up front but that's always been there.

Hope that fill you in. Thank you again for your level of interest.
I plan to introduce shims atop the clip on the needle which should lean out things a little as it will actually lower the needle position. May consider a seperate step of dropping the stock #40 pilots to #35s. All input is gratefully & humbly taken.

DH

[hikermikem]

Just throwing this out there, may or may not help:

I had a similar problem with my old '81 750L, only it was one cylinder that was constantly VERY rich.

Turned out the needle jet in the that cylinder was SO corroded all along the ID that fuel would just flow around the needle, regardless of its position.

Another thing to rule out is spark - are you sure the coils, wires & caps are performing OK?

Good luck, sure is frustrating to chase down a problem.

mike

[nert]

Don't think you need to replace choke seals and plungers, just make sure they are closing and seating all the way.

Yes i know choke would worsen a rich mixture, but, have you tried it to totally eliminate the possibility?

We don't know your tech level, so be patient with our questions.

How long have you had the bike?
How long have you had the problem?

50 mpg or better would be normal. half of that would indicate a much bigger problem than pilot jets.

Did you check the vacuum line to the petcock for signs of sucking in fuel. Maybe plug it off and run the petcock in prime position to be sure.

[suzukizone]

Float level clarification.

Thank you hikermike & nert. I try to walk the thin line between going on & on or not giving enough detail on a sort of long running & detailed issue.

Don't think you need to replace choke seals and plungers, just make sure they are closing and seating all the way.

Carbs are very clean & no signs of corrosion, all plungers move freely & seem to close fully with sufficient slack in choke cable when closed.

Yes i know choke would worsen a rich mixture, but, have you tried it to totally eliminate the possibility?

I could try to test the seal of the plungers with some slight air pressure. Will look into this.

We don't know your tech level, so be patient with our questions.

I often face that question my self. I work at Suzuki/Honda shop with 2 pretty sharp oldtimers who try to guide me through this. I am a slow worker, especially on my own bike.

How long have you had the bike?

Well 1981 GS850G, owned since about 2003. Had at least 20k on it then now proably over 50k. (several instances of speedo cable, drive breakage and replaced speedo/tach with nice used unit some years back) PO seems to have left it out in the weather. Someone had already been into the engine before me, not too gentle either. Had to helicoil several threads for the camshaft caps.

How long have you had the problem?

Some years back was running a bit lean tho ran well seat of pants. Last fall tried to go up one step on mains & pilots to get more color in plugs. Ran crappy & very rich. Went back to stock mains and later stock pilots (115/40) but could not loose the rich running. STRANGE, NO?
Over time things deteriorated in smooth running & compression tests & leak down test indicated most cylinders had both ring & valve issues. Confirmed when torn down including # 2 exhaust valve burnt with some cracks & seat shot.
New pistons, rings, cylinder honed(measured & no bore needed) valve replaced, seat cut, valves lapped & checked, new valve springs all around.
Restored the stock foam air filter from previous K&N. Started with mixture screws out 2 turns but too rich, kept cleaning plugs & setting screws leaner, replaced K&N to help lean out. As engine breaks in it runs better & better & stronger but prob still there once warm at idle with cutting out unless 1300-1500 & previously stated gas guzzling & sooty in the plugs.

Had checked the possible vacuum fuel valve leak possibility. Nothing there, but as always will recheck again. Believe that would show up on #2 cylinder only tho,...no?

Am in the midst of checking the coils as to resistance readings. Initially primary reading looks ok. Will check rest next night or two. Took off tonite to watch America's Got Talent. Wish I did so use them as surrogates as I can't sing, dance, ride a bicycle, do magic etc. :-)

Your questions are great, please excuse my answers. You have given me ideas & homework.

Thanks again so much,
DH

[Mop Bucket]

Fascinating read, wish I could help with the problem. But, I can make a suggestion on replying to multiple questions. I would suggest using the quote button when replying to multiple specific questions instead of pasting the questions. Using the quote button multiple times will help the readers follow the thread. What I do is hit the quote button and copy the question and quote tags to word. Then go back to the thread and quote the next person I was going to respond to. Thanks, hope you find an answer.