Bowl levels are the same, sooooo.....

[Scud]

I was not doing anything on the sly, just checking to see if 'way south Florida' was still on the map.

I agree, the more the merrier especially in my case!! I would not be doing what I am doing if it was not for folks like you Keith.

Thanks!

Scud

 

[gsBert]

wow, scud, do you know how lucky you are with all the ideas youre getting thrown at you? great community here, man im thinking of posting my carb questions in this thread, maybe i'd get some answers...

any wiseguys care to take a crack at my "it lives it lives" thread?

i'm really glad to have joined this forum, we all learn lots from it. and scud. dont you dare just fix your problem and not tell us about it ok?

 

[Scud]

gsbert - I will definetely let everyone know the progression of my problem, as you said, everyone learns from problem, diagnosing and fixing of problems. I am sure that I am not the only one who has had or will have this problem.

And I would have just used my old plugs for the whole process if it were'nt for you suggesting to get four new ones but to warm up in the first place with the old ones so as not to gunk up the new ones.

When I recieve my jets (UPS usually comes around 2:00PM here), I will have them installed that afternoon (probably Friday), I am taking the carb rack off today.

Scud

 

[Scud]

Well, the tracking number told me tomorrow, not Friday so tomorrow at this time I will hopefully have an answer for you guys and pictures of my plugs.

News at 11:00...

Scud

 

[Scud]

Sorry guys....got the new jets in and started her up. After a bench synch only she has great throttle response with a crisp return to idle. Tomorrow I will take her for a ride, vacuum synch, put in new plugs and take her for a ride reading plugs at various throttle ranges and get back with pics and results.

I feel good about this already.

Hope it does not rain..... :?

Scud

 

[Hoomgar]

Rock on 8)


We need to invent a time machine ain't? Never enough time in life it seems?

 

[Scud]

Alright....the verdict... Please see the following pictures for what the plugs looks like. The dark ones are after I synched carbs with my Morgan carbtune. The lighter ones (brand new D8EA as per manual) are from a plug chop after going 35 MPH in fourth gear (Keith Krause suggestion).

I did a half throttle plug chop and all plugs looked like I took them out of the box.....I mean they looked cleaner then new!!! what the He**!!!! This was after a fifteen mile ride, I killed the engine and coasted into an empty parking lot.

Boys......I do not know what to think.....

Number four looks the best on both sets of plugs, sorry about the fuzzy photos.

Scud[/url]

 

[Scud]

Let me clarify...the top photo are the new plugs.

Bottom photo are the old ones (after vacuum synch)

Scud

 

[Hoomgar]

8O

Well I'll leave this one to a pro. It just looks to me like it must be lean lean lean but something else is going on here? Some GS engine voodoo crap.

If the exhaust is new and sealed correctly now, and the carbs are for sure clean in every circuit then it must be elsewhere, valves, something???? I am not sure?

But my guess is simply a lean condition. Yet it runs great? Doesn't make sense. Darn GS engines, they run good even when they are not setup right. Makes it very hard to trouble shoot :?

I am curious to see what others suggest?

 

[Scud]

I'm tellin ya Hoomgar, I cannot figure it out either. She starts up great and purrs at idle, plenty of power through all gears.. :?

New exhaust gaskets that are tight to the header, manifold and wirbox boots are tight, no air leaks. Valves I checked three weeks ago or so and they were within spec also.

When I shut her off there is no clinking or clanking which indicates a hot engine...it is just quiet...

Scud

 

[gsBert]

way too much soot on plug 2, the others look fine.

weird thing is plug 2 has soot up the threads....
it really shouldnt... maybe you didnt have it sealed in properly (1/4 turn after hand tight), that could explain the leakage...

other than that it looks fine to me...
just a tad lean on all the other cylinders, can you raise your needle a notch?

 

[duaneage]

You clearly have a problem with #2. Carb related maybe , could be the vacuum line is pulling fuel from the petcock because of a leaking diaphram.
The needle valves in the float could be sticking open, gum on the slide?

 

[KEITH KRAUSE]

I tried to read back and see how we got to this point.
You did some simple plug/lead swaps that apparently rule out a weak spark or other spark problem.
You also said the compression is good and valves adjusted.
You haven't completely inspected the carbs, but they appear to be clean, good o-rings inside (correct?), same main/air/pilot jets, floats adjusted, diaphragms in good condition (correct?), and synched.
The bike is completely stock except for the pipe just installed.
Up until now the problem was a nearly white burning #1 cylinder. The others looked OK you said.
Now, after the new pipe (which wouldn't cause the latest plug reads) and some carb work (not sure exactly what you did)and re-synching, the reads are different. #2 is very rich suddenly. 1 and 3 look lean and 4 looks decent.
Unless you've done something else not mentioned, it seems more than ever you have a carburetion problem. In the case of #2, you've done something wrong in your attempt to tune. All I can think of with #2, based totally on your info, is you've increased the vacuum somehow. If not the vacuum, then you've done something to change things that you don't realize. You did plug the vacuum nipple at #2 carb to begin the synch? What rpm did you synch at?
As for #1 and 3, they look lean.
If I have this straight, ALL the plugs lightened up, too lean actually, AND looked fairly uniform after a 1/2 throttle chop test? Then the plugs darkened unevenly at a much smaller throttle opening, with #2 showing very rich.
Like I said, the carburetions off. I know you'll swear the vacuum is good.
If you re-check the vacuum and its good at around 2,500 rpm, then you've changed something else. The lean plugs at 1/2 throttle, if uniformly lean, prove the jet needle circuit is too lean. Without knowing the carbs history, anythings possible. Wrong needles/needle jets/diapragm assembly springs...
You should also increase the main as suggested earlier.
As for the pilot circuit, its difficult to say because you have #4 looking OK and by your description, the 1 and 3 plugs darken some, but 2 is too rich.
The pilot circuit, though off, is running generally richer than the needle circuit. But why? You say the carbs are clean, same pilot jets, etc. Have you adjusted the mixture screws? How did you adjust them?
If the bike were here, I'd check the vacuum again. BEFORE the vacuum check, adjust the mixture screws for highest rpm.
This would hopefully work for the pilot circuit and its plug reads.
For the needle circuit, I'd inspect the parts against a picture of the carbs, including factory jetting set up. Being sure all parts are there, are the correct parts and in correct order. If nothing wrong can be found, then I'd say raise the jet needles.

 

[Scud]

gsBert - I have CV carbs and the needles are not adjustable I think. I do snug the plugs up a quarter turn after finger tight, but the soot up the threads is a little confusing.

duaneage - never thought of the petcock problem, I will investigate.

Keith - After I dipped my carbs last year I ordered a set of o-rings from Robert. The diaphragms on all are good, no tears.

I have not done anything else to the carbs except put in the new mains (120). How do you 'increase' the vacuum? Maybe I have been synching wrong. I synch at 2,500 RPM, the vacuum reads 16" on all or very close to that when they are all even. Is this too much? How do you get it higher or lower?

I put a small drill bit in the vacuum hose from the number 2 carb before synching.

The plugs never did look uniform after any plug chop, but they did darken slightly at the smaller throttle opening.

I did adjust the mixture screws to achieve the highest RPM then I lowered the idle and went to the next carb and repeated the process. Funny thing is however that number two and number three did not increase the RPM's when I screwed them in or out, they seemed to stay at the same RPM, what does this tell you?

If there is a way to raise the needles I do not see it, maybe you can shed some light on this, I never messed with them before and do not see how it can be done with these.

I will keep trying all suggestions, keep them coming.

Scud

 

[Anonymous]

Check that petcock. Suck on the vacumm lead. If fuel goes into your mouth then there is the problem. Good luck.

 

[flyingace]

Scud,
This is an old bike. The compression is pretty low and combustion is not going to be crisp like it was when new. I'm not sure pouring over the condition of the plugs is really going to get you anywhere - they may never all look perfect until you rebuild the engine. It's like you're on a spark plug treadmill and can't get off.

You say your bike runs great, and has since the beginning of the thread. Why don't you just enjoy the old girl, and if something goes wrong, at least you'll have a real problem instead of an imaginary one.

Please see the flow diagram in this thread:
http://www.thegsresources.com/_forum/viewtopic.php?t=41590

Ace.

 

[KEITH KRAUSE]

Don't worry about "increasing" the vacuum level(s). You answered a question I had about this. I was wondering (because its happened here before) if you properly/completely plugged the vacuum nipple at #2. If you didn't, you would see an initial low vacuum level when you synched. You would of course increase the vacuum to make it match the others. But in reality you would have too much vacuum once you re-installed the screw. Much higher vacuum would cause a rich mixture.
With such a rich mixture at #2, adjusting the mixture screw correctly isn't possible. I don't know why the mixture screw for #3, which looks lean, is doing the same thing. If the carb is in the condition you say it is, it makes no sense.
As for raising a stock jet needle, many members shim the needle up by installing washer(s). If your bike is a U.S. model, the stock needle isn't adjustable. If you had an adjustable needle, you would see 5-6 grooves near the top and a removable e-clip in one of those grooves.
Obviously, your plug reads have changed with the latest work done. I don't know why #2 has changed so much. The leaky petcock diaphragm is a possibility for sure.
Your 1/2 throttle reads are lean, UNLESS the pics are not showing us what the plugs really look like. We went through this to a lesser extent, with Hoomgars plugs at one point. If they are truly white/lean, then you should raise the needles.
Its easy for some to say just ride the bike, and you may just end up doing exactly that. You can only try so much. Common sense and any basic knowledge of how an engine works will tell you the bike isn't running as it should, even if you are reasonably happy with it. The plugs show you what the cylinders are doing. You've stayed with this because you know somethings wrong.
I think its amazing that some think the problem isn't real or whatever. Lean is lean. Rich is rich. A black plug is acceptable? White also? You would like to fix this. This thread is about trying to fix it, not closing your eyes to whats happening and quit on it. Easy to do when its not your bike.
At least you've tried. Sure, there's many other possibilities and some are not common occurences. It can also get very expensive trying to eliminate any possibility one by one.
I would still, right or wrong, inspect all the parts, check that petcock, check synch, etc. Something happened to make #2 go dark. If the plugs are nearly white at 1/3 to 1/2 throttle, then the needles need to be raised.

 

[flyingace]

Scud,
Go ahead and keep your bike in the garage. That's where some would have you keep it until hell freezes over.

 

[gsBert]

i agree with flying ace: keep it garaged, NOT! what a jerky sort of statement to make, but i see his point, if it fewel sright, ride it...

however, i think yu need to raise your needles on all 4 cylinders and figure out why #2 is running rich all of a sudden.

let me repeat myself here: YOU SHOULD NOT HAVE SOOT ON THE THREADS. my guess is plug 2 isnt screwed in all the way or cross threaded (you couldnt have cross threaded it could you?) so make sure all the threads are clean, and make sure its in right (i actually use anti-seize on my plugs as lube after brushing everything off (plug and head)), sure it smokes a bit at first but then its ok after like 20 seconds...

so if you dont have clips on your needles, use small washers to raise them a bit, 1/16 of an inch at a time.

also make sure no extra fuel is getting into #2 (petcock?)

redo the plug wire swap (to make sure #2 is firing allright, swap it (the wire) with the other plug from the same coil)

if 2 is still rich, look into the petcock or the carb, but i dont see it being the carb...

did you install the larger mains yet? if yes, raise those needles...

also make sure the top of your slides are getting athmospheric pressure (you didnt block the intake to them with cheap pods did you?)

i bench synch my carbs with a vacuum cleaner, just be careful because your engine will pulse vacuum and the cleaner will be constant (engine suction also varies, cleaner will be constant unless you install a rheostat on the 120v outlet), but it lets you see what happens, ie: how your slides move in relation to throttle... plug those vacuum nipples dude! make sure all 4 slides behave the same...

if you want to pay for the shipping, send me your carbs, ill send you mine (i got a very functional 750) this will forever remove the "is it the carbs" question...

i just wish you were near me, we'd swap parts in meh garage and find out real fast whats wrong...

man, i love carbs! my next bike will be fuel injected....

 

[KEITH KRAUSE]

Scud,
Go ahead and keep your bike in the garage. That's where some would have you keep it until hell freezes over.

Jeez! :roll: Why don't you take it personal?
Scud is trying to figure out a problem that he himself brought up. He brought it up because he knows this shouldn't be happening.
He's made a good effort trying to fix it. It may get fixed, it may not. What to do is his decision.
He asked for help on fixing it. Not opinions on how to live with it.
Don't get sensitive when faced with facts or accuse others of giving advice for the purpose of keeping a guy off his bike.
I think much of my advice at this site has helped KEEP a lot of guys RIDING their bikes. 8)