GS650 - Needle Jet Plat and Main Jet Removal Tips?

[DaveP]

BS32SS carburetors. Doing my first carburetor rebuild.

Started with carburetor #1 and have everything taken apart except for the screw holding the needle jet plate and the the main jet.

I have JIS screwdrivers, but I am afraid I am going to strip the needle jet plate screw and the main jet is just not budging. I have left things over night sprayed with carb cleaner and liquid wrench and will try again tonight.

Any tips for getting these last parts off without doing damage?

Thanks,
Dave

 

[JTGS850GL]

What are you calling the "needle jet plate"? Where is it located?

The only real trick to getting the main jet out is to use a screwdriver that exactly matches the slot in the jet. Using a driver that's too thin or too narrow will most likely give you problems.

Do you have an impact screwdriver set? I've found them to be most helpful on stubborn screws.

 

[DaveP]

The red circle on the photo shows the plate.

Part no. 45 on this diagram: http://www.bikebandit.com/1981-suzuki-gs650gl/o/m21423#sch258417. I should have said needle valve plate.

I wasn't sure that an impact driver was the appropriate tool for carburetor work.

 

[Steve]

That would be "INLET NEEDLE" or "INLET VALVE", there is no "jet" involved there.

An impact driver with a good bit does wonders there.

I have never had to use an impact on the main jet, a well-fitting driver has always been sufficient.

.

 

[tkent02]

The hand held impact, a tip that fits the screw well, that you tap lightly with a hammer is the tool for this.

 

[Guest]

A pair of vise grips will work on that plate screw.

 

[tom203]

Of course, you did remove the mixture screw stuff hidden behind the plug???? (on top of carb throat on engine side)

 

[JTGS850GL]

That main jet slot looks pretty buggered up. Suggest using a better screwdriver in the future. You may have to cut a deeper slot into the main just using a hack saw blade and giving it another go with a better fitting screwdriver. In your case you may have to use a hand impact driver on that one.

 

[DaveP]

99% sure that everything else that needs to be removed has been removed. I was following the two BS(CV) tutorials on http://members.dslextreme.com/users/bikecliff/

Is there a known screwdriver size/make that is best for the main jet?

 

[tkent02]

A good quality one that fits tight.

 

[JTGS850GL]

Take your jet to the store and see which one fits best. You'll want to take a Main, Pilot, Pilot air and the Fuel Mixture Screw with you.

As for the one that's stuck and all buggered up, I know of no screwdriver that's going to fit that one correctly.

 

[850GT_Rider]

The red circle on the photo shows the plate.

Part no. 45 on this diagram: http://www.bikebandit.com/1981-suzuki-gs650gl/o/m21423#sch258417. I should have said needle valve plate.

I wasn't sure that an impact driver was the appropriate tool for carburetor work.

Those were buggered up as well on the set of carbs I'm doing now. They were so full of rust and corrosion that you could barely tell they were machine screws. Looked like round rivet heads. Soaked well with PB Blaster. Wire brushed until i could get to the slots. Dental pick for final clean-out.

None of my impact driver bits would fit those. I have a set of JIS screwdrivers, but I found that a #1 Phillips screwdriver fit the closest. Flattened the point on the end of the screwdriver just a bit for a better fit. Then with LOTS of downward pressure to keep the screwdriver from 'walking' out, got two of them to break loose.

On the other two, ground a slot with a fine cut-off wheel on my Dremel and was able to use a standard flat-blade. Again, LOTS of downward pressure to keep the screwdriver blade from walking out.

As others have said - the importance of screwdrivers that exactly fit each individual jet or fastener can't be over-emphasized. Remember - you can't have too many tools!

 

[JTGS850GL]

I've found that a set of needle nose Vise-Grips is a tool I can't live without.

 

[DaveP]

Main Jet is Out

Main Jet is Out

Rather than run around looking for another screwdriver tonight I filed down my 5/16" screw driver until it fit just right. The main jet is not buggered up as bad as it looked in the original photo. A little bit, but more knocking the varnish off.

Still need to work on the needle valve plate, but can't work on it again until Wednesday night. I'll let it soak some more, but will probably need to find a new screw for this one and most likely the other three carbs if they have the same corrosion.

 

[Guest]

Just grab that plate screw from the side with a pair vice grips & that screw will break free in a heartbeat...

The main jet might need a torch shot on the outside to expand things a bit.

 

[silverhorse47]

Just grab that plate screw from the side with a pair vice grips & that screw will break in a heartbeat...

Gosh, but would it break in the right way?

S.

 

[Guest]

Gosh, but would it break in the right way?

Just grab that plate screw from the side with a pair vice grips & that screw will break free in a heartbeat...

Good point, fixed it...

 

[DaveP]

Lisle impact driver with a JIS #2 bit took it off with just a few taps. Wish I didn't waste so much time on other attempts.

 

[Steve]

We kept tellin' ya.

Thanks for finally listening.

.