leaking choke plunger solution???

[suzukizone]

I believe my overrich prob on the '81 GS850G may be near solving & if so will gladly post verbage & pics.

In the meantime I was wondering if anyone knows if there is a source for the "gland nut" (is this the term???) that is the open nut with rubber seal that holds the choke plungers in place on the carb body.

I know Suzuki & Mikuni never offered the plunger parts nor even acknowledged them. Can't figure this but I believe I have found out how to replace them with brand new plungers with nice new soft rubber seats. Mine look quite bad with rough & cracked rubber seats.
Anyway if anyone has a lead please let me know.
Thanks,
DH

[Nessism]

The choke plunger nut/seal don't often cause problems, so I think your best bet is to post an ad in the Parts Wanted forum for some new/used ones. I've never heard of these causing an over rich condition so looking forward to how this works out for you.

BTW, it goes without saying that your carbs need to be properly cleaned and the O-rings refreshed before you can troubleshoot running problems. Feel free to check my signature for a link to a carb rebuild tutorial and Newbie Mistakes thread which you may find useful.

[chuck hahn]

Sudco may have them.

[londonboards]

Hello and welcome.

I had no problem sourcing all the rubber pieces from my local Suzuki dealer (Robinsons in the UK) including both of these chokes pieces:

http://2.bp.blogspot.com/-rSfXPPraP4I/URqrUkVbnRI/AAAAAAAACww/i6cCW95zKn8/s1600/P1050716.jpg

I also found a seal missing in the butterfly valve rod so I replaced the whole lot:



See My Blog here: My Suzuki GS1100G Blog

But I agree, I would find it difficult to believe the chokes themselves are damaged.

Greetings

[tom203]

If you follow this link to this ebay's seller store- you'll find he has lots of carb parts like this-both new and used. He might know something..

http://www.ebay.com/itm/KAWASAKI-KZ1000-KZ-1000-KX80-GS1000-GS750-GS550-MIKUNI-CARB-CARBURETOR-CHOKE-/300861370813?_trksid=p2045573.m2042&_trkparms=aid%3D111000%26algo%3DREC.CURRENT%26ao%3D1%26asc%3D27%26meid%3D6355489763121736198%26pid%3D100033%26prg%3D1011%26rk%3D1%26sd%3D300861370813%26

I've been assuming that if there was a problem with the rubber on these plungers, you'd more likely get a lean condition

[chef1366]

That is not your problem.
I have some if you still think it is.

[suzukizone]

leaking choke plunger solution???

First & foremost, thank you all for you prompt replies. I believe I mis-described the situ. The bad rubber is NOT on the outer seal or "O" ring of the "gland nut (???) that londonbaords showed, but the rubber face on the actual plunger end that would seal the extra gas off when choke is close but allow it to flow when knob is lifted. See my attachement.

I could only remove the LH carb side as carb set still on bike. There are radial cracks spreading out from the "pin" and across the circular sealing area. I know the full extent of this condition doesn't show up well in my pic but clear as a bell with 10x magnifier.
The overrich occurs THROUGHOUT the throttle range and has dropped my mileage by 10mpg. BTW have a K&N filter (airbox type) so that should help bike run leaner. Stock foam filter carbons up the plugs real quick.

This occurred soon after the bank of carbs was run through an ultrasonic cleaner. All replaceable jets(including the air jet in the intake throats of carbs), float seats & needles, gaskets etc replaced with brandy new stock size SUZUKI parts. Float level micro managed, checked & re-checked with carbs open & then with tube to visually inspect gas level. This work was done over a long period of time when I worked at Suzuki dealer under guidance of 3 senior & very detail oriented mechanics.

Carbs were synched. Realize you have to take my word for this (or not:-) but no stone was left unturned & work was triple & quadruple checked. This seems to be the only way anyone could figure how the overrich condition could be so global.

Don't want used parts, SUDCO confirmed MIKUNI never offered or acknowledged existence of these plungers. Nor did SUZUKI (check your parts diagrams)
Anyway hopefully this works.

Wanted a second set of the brass gland nuts as I have to drill out the holes a hair to fit the modified Yamaha plungers & will have to trust my judgement as onced drill won't work right with stock plungers.

If anyone feels the old SUZUKI parts can''t be the problem & that used are OK well they can be yours for the price of postage when I'm done. Sorry for novel but I realize I wasn't clearly describing earlier.
Thanks & any further idears or encouragement always welcome. This site is the best!
DH

[suzukizone]

leaking choke plunger solution???

TO: chef1366. If you mean you have a set of 4 of the brass gland nuts, (like in the first pic that londonboards posted)I'd have a real interest so I can have 4 to modify & 4 still stock if I have to replace my orig plungers. Lemmee know,

Thanks,

I remain, to the dismay of family & friends,

DH

[londonboards]

Oh yes I see now. Just looked at my plungers:



sorry I haven't got a pic showing the bit you are having a problem with. All my plungers are currently out and they are 30 years old and do not look anything like yours. My rubber internal parts look fresh with no markings and certainly no cracks. If you are in any doubt I would replace the whole piece. I am no expert though. Take advice from others with greater knowledge.

Greetings

[suzukizone]

leaking choke plunger s

"Take advice from others with greater knowledge." So very philosophical mate :-)


With my feeble geezer brain that is an easy task to perform. Like I say the reality of the condition of the rubber seat is noticeably worse than the pic shows.

If this process works, I will try to figure how to create a verbal & visual presentation. Maybe it can make it's way into the tech files in case others run into the running issues I've had.

Here is another image with the orig & Yamahammy plunger & methods of adapting to my linkage without fancy machining work. The fat end of the pieces & "pins" are the same dimensions & the plunger slides nicely into the carb & sets properly. The length(tho not the diameter) of the main part of the shaft is also the same. The last bit at the end is where the differences lie. I hope to drill out the gland nut to the approx 1mm larger diameter of the shaft & use a Yammy outer seal to match.

Waiting to hear from Mike's if they just might have the nut that matches & I won't even have to drill. That part is listed with a part # (2A2-14171-00-00) by Yam but all list it as NOT AVAIL. SO sad.

Thanks for your reply.

DH

[Zero260]

I think something like this might be my problem also. I have an 81 gs850g and I am also rich across the board. I've had my carbs apart and cleaned several times and set my floats a little higher(lower fuel level) just to keep it from fouling out plugs at idle, and I get 25-30mpg. Did your solution work for you?

I'm thinking about replacing the whole plunger, or maybe the spring with a slightly tighter one.

[suzukizone]

leaking choke plunger solution???

After posting this question several times over the years, spending a great amount of time & some money I have come to this conclusion. IF the choke plungers are the problem there is essentially no hope. They were NEVER available from Suzuki. Never listed as a part. Mikuni disavows all knowledge of the part. They will refer to to SUDCO. Sudco hasn't a clue. Suzuki must have ordered a set number of this custom carb design and for some reason no one thought the plungers needed to be given any status.

If you find a used set of carbs, you might be VERY lucky that those plungers just happen to be OK even though they are the same age as yours.

DO NOT order the plungers offered by Mike's XS. They look like they might work with minimal machining. Ain't gonna happen.

So this info is based 100% on my experience over many years of frustration. My bike guzzles gas but runs like a champ. I just live with it. Too old & stupid to hassle this out any more.

Please someone prove me wrong, not with theory or opinion but with a tried & proven solution.

I leave soon after dawn for a 2 day ride & camp trip on Roadkill & the rest of the world can
just spin by me.

I remain, to the dismay of my family & aquaintences,

DH

[rustybronco]

The radial cracks viewed at 10X aren't the problem.

The overrich occurs THROUGHOUT the throttle range and has dropped my mileage by 10mpg.

The choke plungers may be held open for some unknown reason, but in no way are those plungers the reason for a 10 mpg drop in fuel economy.

[suzukizone]

leaking choke plunger solution???

Please explain further. Want to understand. To me if the plungers do not seal fully, why wouldn't that allow the system to be supplied with excessive fuel throughout the range since their being opened at various positions is what allows the richer starting mixture? To me it seems that is what would happen but still trying to understand it all.
Thanks.

DH

[rustybronco]

Being able to seal properly and not being allowed to seat completely are two different things. To me, those choke plungers, if they are all like the one shown, appear to be able to properly seal off the fuel passage in the fuel enrichment circuit if allowed to. Now, if for some unknown reason, the linkage that actuates (lifts) the choke plungers didn't allow them to seat all the way, or they bind in the brass nut they ride in, then the enrichment circuit would allow more fuel than the engine requires to run efficiently.

Understood?