Fuel screw won't budge. How to remove?

[halvorja]

I just purchased a 1980 GS850G and am rebuilding the carbs. I have followed the how-to on this website and have everything apart and currently soaking overnight in carb dip except for the fuel screw (called air screw in how-to) on #1 carb. It is obvious that someone has been messing with these screws because the other three were a little mangled on top. Well, this one on the #1 carb is really stuck in there and the top is pretty stripped.

So far, I've used a lot of carb cleaner and also penetrating spray. I've also tried tightening the screw to get it to come loose, but that didn't work. I also tried heating the area of the carb around the screw very lightly, but it still didn't budge. Finally, I grabbed a smaller screwdriver, cut thin pieces of sandpaper and tried sanding in the old slot (took forever). When I did this, I could grip the screw well with a screwdriver, but it still didn't budge.

Is my only remaining option to drill into the fuel screw and use an extractor? I have a replacement fuel screw ordered in any event.

One more question. As far as I can tell, I should set the fuel screws at 1-1/2 turns out as a starting point, right?

Thanks a lot,
Jake

[TomK]

I just purchased a 1980 GS850G and am rebuilding the carbs. I have followed the how-to on this website and have everything apart and currently soaking overnight in carb dip except for the fuel screw (called air screw in how-to) on #1 carb. It is obvious that someone has been messing with these screws because the other three were a little mangled on top. Well, this one on the #1 carb is really stuck in there and the top is pretty stripped.

So far, I've used a lot of carb cleaner and also penetrating spray. I've also tried tightening the screw to get it to come loose, but that didn't work. I also tried heating the area of the carb around the screw very lightly, but it still didn't budge. Finally, I grabbed a smaller screwdriver, cut thin pieces of sandpaper and tried sanding in the old slot (took forever). When I did this, I could grip the screw well with a screwdriver, but it still didn't budge.

Is my only remaining option to drill into the fuel screw and use an extractor? I have a replacement fuel screw ordered in any event.

One more question. As far as I can tell, I should set the fuel screws at 1-1/2 turns out as a starting point, right?

Thanks a lot,
Jake

Mine was the # 3 carb. These stuck air jets are a real pain. Take your time and think through everything before you get in deep dodo. One thing I noticed after drilling mine out was a small amount of a glue like stubtance. I have read where the factory applied a small amount of lock-tite to hinder users from adjusting this screw. If I had to do it again, I would try soaking the cavity with MEK or some other strong solvent. Don't be afraid to take the carb to a local machine shop and spent $ 20.00 or so and let them mill it out on a bridgport.

Tom

[headsbikesmopars]

Jake, try heating the area with a propane torch (low heat) and while hot melt a candle and allow to drop onto the screw. The heat will cause the wax to be 'pulled' down into the threads. This has always worked for me on those carb screws. They will turn out sooo smooth. I learned this from an 'old' machinest.

[halvorja]

Thanks for the advice fellas. In the past I have used the heat thing on seized metal parts, but I'm a little hesitant this time around since I'm not working with steel. I'll try to heat it and use wax. If that doesn't work, I think I'll take it to a machine shop. I wouldn't want my hand drill to slip and knock out the threads.

Jake

[lapls]

If the calibrated hole is not damaged I would just leave it there and clean the hole.. There is no rubber or wearing part so removing it for cleaning would not add any value ( unless you want to put a larger-smallet air jet ).
My 2 cents..

Sylvain
GS650GL
XS650SG

[halvorja]

If the calibrated hole is not damaged I would just leave it there and clean the hole.. There is no rubber or wearing part so removing it for cleaning would not add any value ( unless you want to put a larger-smallet air jet ).

On my carbs, there is a spring, metal washer, and an o-ring under there. I still want to dip the carb, so I really need to get it apart since the o-ring will magically disappear after the dip. Plus, it would be very disappointing if I got everything back together, slapped the carbs onto the motorcycle, and found that I needed to adjust the screw.
I probably didn't explain the part I need to remove very well and you may be thinking of a different part of the carburetor. Sorry about that.

Jake

[lapls]

Hi,
Yes, I thought you were refering to the pilot air jet, teh one on the carb throat...
Good luck!
Sylvain
GS650GL
XS650SG

[halvorja]

Well, I got it out. I spent about 5 hours trying the heat/wax method and I actually got the screw to move; however, I just couldn't get it going well enough to warrant continuing this (I only got it to move about 1/3 of a turn after all that time).

So, I drilled into the screw and used an extractor. In the event of a worst-case scenario, I could use the screw again. That shouldn't be an issue since a new one is on the way.

Thanks everybody,
Jake