Finally fixed my #3 black & sooty plug...

[hikermikem]

During the process of tuning my newly cleaned/rebuilt carbs on my GS850GLZ, I found that the #3 plug was ALWAYS black & sooty.

A previous thread gives all the details: http://www.thegsresources.com/_forum...d.php?t=132224

Anyway, I found the problem:

Thinking back to when I dis-assembled the carbs, I remembered having trouble getting one of the jet needle seats out. In fact, I kinda buggered up the end a bit & had to use a small rat-tailed file to gently remove some raised edges on the ID at the "seat" end.

When I re-installed the jet needles back into the slide assemblies, I also "raised" each needle .040", by removing the little plasitc spacer (.110" thick) & replacing it with 3 washers (total thickness of .070"). I did this on all 4 slide assemblies.

Well... apparently my "gentle filing" had the end-effect of raising the needle about .030". I replaced the 3 washers on the #3 needle with a plastic spacer that measured .100".

Voila!! The black sooty plug disappeared!! I'm still tuning the carbs & waiting for my Morgan Carbtune to arrive so i can sync them, but the excessively rich condition on #3 is now gone.

mike

[TheCafeKid]

During the process of tuning my newly cleaned/rebuilt carbs on my GS850GLZ, I found that the #3 plug was ALWAYS black & sooty.

A previous thread gives all the details: http://www.thegsresources.com/_forum...d.php?t=132224

Anyway, I found the problem:

Thinking back to when I dis-assembled the carbs, I remembered having trouble getting one of the jet needle seats out. In fact, I kinda buggered up the end a bit & had to use a small rat-tailed file to gently remove some raised edges on the ID at the "seat" end.

When I re-installed the jet needles back into the slide assemblies, I also "raised" each needle .040", by removing the little plasitc spacer (.110" thick) & replacing it with 3 washers (total thickness of .070"). I did this on all 4 slide assemblies.

Well... apparently my "gentle filing" had the end-effect of raising the needle about .030". I replaced the 3 washers on the #3 needle with a plastic spacer that measured .100".

Voila!! The black sooty plug disappeared!! I'm still tuning the carbs & waiting for my Morgan Carbtune to arrive so i can sync them, but the excessively rich condition on #3 is now gone.

mike

Congrats!! funny how that little bit of a difference can make a HUGE difference...lol

[BassCliff]

Thanks Mr. hikermikem,

This is very good information. Thanks for sharing your findings and your fix. This will add nicely into the body of information I'm collecting for when I tackle my carbs.


Thank you for your indulgence,

BassCliff

[hikermikem]

Congrats!! funny how that little bit of a difference can make a HUGE difference...lol

No kidding!! When you told me about your jet needle washer screw-up it got me to thinking about mine, then I remembered about my little filing job. I didn't track where that needle seat went, but I would bet it's in #3.

Can't wait for the Carbtune to show up - I have 3 bikes waiting to get properly sync'ed!

mike

[hikermikem]

Thanks Mr. hikermikem,

This is very good information. Thanks for sharing your findings and your fix. This will add nicely into the body of information I'm collecting for when I tackle my carbs.


Thank you for your indulgence,

BassCliff

Glad this may help you - I know you have an 850 too.

[TheCafeKid]

I also found that grinding them down with a grinder increased their thickness. or just raised the edge anyway. Made for a pain to find close to matching ones. I wish I knew where to find the little ones you guys get that fit perfectly. I asked at a couple of radio shacks, and they looked at me like I was insane...lol

[hikermikem]

I wish I knew where to find the little ones you guys get that fit perfectly. I asked at a couple of radio shacks, and they looked at me like I was insane...lol

I got mine at the local Radio Shack, but I couldn't find them in a "stand-alone" bag. Where they sell the little nuts & screws, is a bag which contains an "assortment" of flat washers - 20 each of 4 or 5 different sizes. It's the smallest washer in that bag (#4 size I believe).

Those fit perfectly & their thickness ranges from .021" - .024".

Easier then grinding them!

mike