Stripped one of my idle mix screws

[SlowBox]

I have a pretty significant off idle stumble and tried to fix it today but got hung up. All 4 of my mixture screws are pretty corroded in their respective carb bodies, but one in particular was a bitch and I ended up rolling the slot out of the screw head trying to seat it and get a baseline.
What are my options now?

 

[dannymax]

I have a pretty significant off idle stumble and tried to fix it today but got hung up. All 4 of my mixture screws are pretty corroded in their respective carb bodies, but one in particular was a bitch and I ended up rolling the slot out of the screw head trying to seat it and get a baseline.
What are my options now?

Drill and an EZY will work. Or another carb body. Which carb is it?

 

[SlowBox]

Drill and an EZY will work. Or another carb body. Which carb is it?

Front right, I forget how they're numbered. It's not hurting anything not being able to be adjusted, it's just gonna bother me.

On the up side, I pulled the needles and found the previous owner attempted to shim them, but installed the washers on the wrong side of the head. I'm interested if I'll see any driveability improvement tomorrow during my ride in to work.

 

[sdt354]

I think you'll get the needle out doing what Danny mentioned. It's not frozen in place. So you're ahead of the game. I've had to drill the heads of the needles right off to get them out when frozen. I'll bet a left hand drill would catch and spin it out too. A 1/4 drill bit will give you a perfect center spot on the neddle head. The tunnel will guide it straight. Just make a center mark, then go in with the little drill bit and easy out. Cap off the holes when done. The plastic hole plugs sold at ACE Hardware work good.

 

[SlowBox]

I think you'll get the needle out doing what Danny mentioned. It's not frozen in place. So you're ahead of the game. I've had to drill the heads of the needles right off to get them out when frozen. I'll bet a left hand drill would catch and spin it out too. A 1/4 drill bit will give you a perfect center spot on the neddle head. The tunnel will guide it straight. Just make a center mark, then go in with the little drill bit and easy out. Cap off the holes when done. The plastic hole plugs sold at ACE Hardware work good.

Excellent advice. The bike acts like it is supposed to with the mixture screws at 3 turns out and the needles shimmed to .020".

Anyone got an idle mix needle they'll throw in a bubble mailer and send my way?

 

[alorio1]

If you get it out look for a washer and O-ring behind the screw spring thats suppose to be there also.

 

[leco68]

If I may hijack this thread - I'm rebuilding my carbs and stripped the head of one of the A/F screws and thought I'd follow the advice below, but I made one major mistake; I didn't make just a dent with the drill bit, I went too far; way too far. My bit fit perfectly down the tube and I ended up taking the threading off the wall of the tube! Doh! :bang head:

Any advice on what to do next? Am I forced to find a new carb body? Can I rethread the tube? Sigh.

Thanks!

Percy

I think you'll get the needle out doing what Danny mentioned. It's not frozen in place. So you're ahead of the game. I've had to drill the heads of the needles right off to get them out when frozen. I'll bet a left hand drill would catch and spin it out too. A 1/4 drill bit will give you a perfect center spot on the neddle head. The tunnel will guide it straight. Just make a center mark, then go in with the little drill bit and easy out. Cap off the holes when done. The plastic hole plugs sold at ACE Hardware work good.

 

[davesax36]

Which body did you destroy. Danny, Sean, or Kyle would be the guys to ask about those parts.

 

[dannymax]

If I may hijack this thread - I'm rebuilding my carbs and stripped the head of one of the A/F screws and thought I'd follow the advice below, but I made one major mistake; I didn't make just a dent with the drill bit, I went too far; way too far. My bit fit perfectly down the tube and I ended up taking the threading off the wall of the tube! Doh! :bang head:

Any advice on what to do next? Am I forced to find a new carb body? Can I rethread the tube? Sigh.

Thanks!

Percy

A machine shop might be able to press in a thread insert depending on the hole dia., amount of damage, etc.

You will probably have an easier time of it, and be back on the road sooner, by replacing the carb body. I probably have the one you need....shoot me a PM.

 

[one2dmax]

The replacement carb body is easiest route for sure. We have repaired stripped threads with an insert as noted.

 

[leco68]

Thanks for the reply guys! You have given me hope again! I was pretty bummed last night when I realized what I had done.

It was carb number 3 - the bottom right when viewed from the seating position.

I'm actually not in a huge hurry to get the max on the road since I am waiting to sell my MINI to help fund the bike work. The bike is a 1985 and the carbs have never been touched and the fuel tank needs a recoating.

I'm currently tearing down the carbs and cleaning them so I'll know what parts need to be replaced. The carbs have definitely never been touched and are very dirty.

I will connect with you guys so I understand costs and timing.

Percy
(finding this board to be extremely helpful!! unk

The replacement carb body is easiest route for sure. We have repaired stripped threads with an insert as noted.