Carb tear down issue...

[Schafudd]

Good morning,

I picked up an 1982 GS850L this pasted weekend on Craigslist. It was stated at time of purchase that the carbs would need to be broken down and cleaned, no biggy.
Well I'm in the process of tearing them down and with the exception of carb #1 the pilot air screw heads are sripped and don't budge. It also looks like the threads in the barrels of the pilot screws MAY be marred up a bit.
I guess my question is... Should I cut my losses and buy 3 new carbs? Do I attempt to lefthand drill the small screws?
Kind of at a frustrated loss at this point.
Thanks for any help,
Scott

p.s. Thanks to BikeCliff his site has been amazing help already.

[Steve]

First, let's make sure what "screws" you have, because there are no "pilot air screws" on your carbs.

The only "pilot air ..." that you have are jets, and they are in the intake throat, at about the 8 o'clock position. That is about the only thing that won't matter much if it's not removed for dipping, as no fuel goes through its passages to get gummed up.

My guess is that you are talking about the "idle mixture adjustment screws", which are on top of the outlets. Am I right?


There have been many threads on how to get those screws out. One method that I have used many times is to use a Dremel tool with a large cut-off wheel to cut a slot down the 'tower' and into the head of the screw, cutting a new slot.

These two carbs have had that treatment.


Of course, you should be soaking the screws with PB Blaster and/or using heat to help free things up, and be sure to use a new screwdriver, or at least one with fresh, sharp edges, so they don't slip.


By the way, if you do get new carbs, I would b interested in your old ones.

.

[Schafudd]

Thanks much Steve,
I had heard mention of the slotting meathod... thanks a ton for the pics i wasn't 100% sure of the process. I appreciate you taking the time to post those.
I'll let you know how it goes... looks like i'm buying a Dremel 4000 on the way home. Yay new toys!

yes you were correct I was referring to the Idle mixture screws, I was just using the name from the tutorial i was following.

They have had several doses of liquid wrench and a small torch.

Thanks again.
Scott

[Steve]

If possible, try to position the new slot so it matches the existing slot in the screw, so you don't have to go quite as deep for fresh metal.

That is not always possible, so just make sure you have gone deep enough that you have enough strength in the sides of the new slot in the screw so you don't strip them out, too. If that happens, it's time for the left-handed drills.

.

[BassCliff]

Greetings and Salutations!!

Hi Mr. Schafudd,

Have you clicked here yet? New Members, CLICK HERE!!

I suspect you have, but I can't help myself.

Have you seen Mr. Nessism's carb tutorial? It's a bit more thorough. There's a copy on my website:

Mikuni BS(CV) Carburetor Rebuild Tutorial (PDF file)
(Mr. Nessism)

Welcome to the forum. Keep us informed.


Thank you for your indulgence,

BassCliff

[Schafudd]

Cliff,

Yeah I've checked it out... It's gas soaked in my garage right now!
It's the tutorial I've been using to do the tear down.

thanks so much for your site, it's a once stop librabry for all things GS. Mountains of help!

[Nessism]

First, let's make sure what "screws" you have, because there are no "pilot air screws" on your carbs.

The only "pilot air ..." that you have are jets, and they are in the intake throat, at about the 8 o'clock position. That is about the only thing that won't matter much if it's not removed for dipping, as no fuel goes through its passages to get gummed up.

My guess is that you are talking about the "idle mixture adjustment screws", which are on top of the outlets. Am I right?

.

Steve,

According to the Suzuki FSM for the GS850, GS650, GS550 (the manuals I checked), Suzuki states the proper name for these screw are "Pilot Screws".

[Steve]

Steve,

According to the Suzuki FSM for the GS850, GS650, GS550 (the manuals I checked), Suzuki states the proper name for these screw are "Pilot Screws".

True enough. I just checked the manuals that I have on file and find the same thing.

So where did I get the term "idle mixture adjustment screw"?

I do like it better than "pilot screw", though.
The VM carbs have "pilot fuel screw" and "pilot air screw", but the BS carbs only have a "pilot screw".
Kinda screws up the thinking there, and the newbies just won't know what to call it any better than they do now.

Would you object greatly if I keep calling it that?

.

[Schafudd]

SUCCESS!!!

all tore down except for one jet per carb... need a different screw driver.

THANKS SO MUCH FOR ALL YOUR HELP!

[Schafudd]

Well all carbs are cleaned everything was assembled last night, started it up real quick just to make sure it would.

The bike ran great with the choke but died as soon as the choke was off.

I have to do the idle screw tuning and i have a vaccuum syncro so i can do that too.

Choke shouldn't be used when doing any tuning correct? I know dumb question.

Thanks to GSR for being a great and knowledgable place.

[cableguy]

SUCCESS!!!

all tore down except for one jet per carb... need a different screw driver.

THANKS SO MUCH FOR ALL YOUR HELP!

Do you mean pilot screw driver, idle mixture adjustment screw driver, or
pilot screw driver?

[MisterCinders]

Well all carbs are cleaned everything was assembled last night, started it up real quick just to make sure it would.

The bike ran great with the choke but died as soon as the choke was off.

I have to do the idle screw tuning and i have a vaccuum syncro so i can do that too.

Choke shouldn't be used when doing any tuning correct? I know dumb question.

Thanks to GSR for being a great and knowledgable place.

Use the choke to warm the bike up. After that do not use the choke when tuning or synching the bike.

[Schafudd]

I'm a dummy it wouldn't run sans choke because i didn't set the Idle screw on the bottom of the racked carbs, it was in but not pressing and giving any juice.