idle mixture screws won't turn

[bluscat]

idle mixture screw slot for screwdriver stripped out,plus they are either tight or are rusted in' I have soaked them in wd-40 and tried a impact driver,they were already strpped when I got the bike and it had been sitting for about 3 years, I can't get the idle down under about 2,000 RPM's.
Has anyone tried drilling them out and using a easyout, or does someone have a better suggestion?
Also, would they still be available through a dealer, if not where would be a place to get 4 of them for a 1982 XJ1100?

[Crazcnuk]

I have one like that. I bought a set of reverse drill bits, but have not yet tried to take it out.

I figure, since the screw is not tight (just held ther by the spring tension) the reverse bit should spin it right out if it can get a bite.

No point for me to try, until I have one to replace it with!

[John]

IB Huh?

I used to live there in the early 80's. My squid days at Coronado. One thing you can try is carefully cut the material away that forms the bore that the screw sits in, just to the top of the screw heads, and possibly be able to cut a new slot in the screw head. If the carbs are dry, and no residual gas is left in them, a propane torch can be used to heat the aluminum around the screws to expand it, and free the screws. The torch will not get hot enough to melt the metal, but will take out the O rings on the screws. They can be found at any place that specializes in seals and O rings. The size is 3mm OD by 1mm thickness. I have a place locally that deals in nothing but O rings.

[prometheus578]

"Just a thought..."

I can't get the idle down under about 2,000 RPM's.

Not to poke fun or question your knowlege.... but have you tried turning the idle speed screw/wheel?
(Some people get the two concepts mixed up.)
Of course, then there's still the issue of your "non-turning mixture screws.

[81xsproject]

What John said is the way to go. I had the same issue on my eleven when I first got it. I put a cutting stone on my dremel and cut down the center of the bore until the screw was notched. Then, I carefully into the cylindrical bore from the front being careful not to go all the way through. Take some pliers of some sort and work the cut piece back and forth until it breaks off.

Now before you go stripping your new slot, spray a bunch of penetrating oil into the hole and heat it up slightly with a little torch. Let it sit overnight. When you come back, get your screw driver ready, and some more oil, heat it well with the torch until the oil is smoking, and with good pressure into the screw give it a good, quick, firm turn and it should break loose. If not, repeat the heat and try again.

This worked for me on the mixture screws and other than the cutting, it helped me get my pilots out as well.

[fredintoon]

What has worked for me to remove those super soft brass parts when the slots are wrecked is this:-
Put a long series screwdriver bit in your drill press. Do NOT have the drill press running. Block the carb body up on the drill press bed and bear down hard on the drill feed lever to force the screwdriver bit into the wrecked slot. Turn the drill press chuck backwards by hand to back the screw out.

[egsols]

Do NOT have the drill press running


LMAO

Seriously though, sounds like a good idea, never thought of that myself, I'm going to try that sometime. Usually use heat.

[Crazcnuk]

What I can't figure out is how anyone can put so much force , on the mixture screw, that it strips the head out!

If a person is so torque challenged they strip a mixture screw, what the heck do all the other bolts and screws, on thier bikes, look like!

BTW if anyone has a spare idle mixture screw, for an 80 carb, I could sure use one. I can get one from MikesXS but the postage, for just the one item is a killer.

[BrianB]

Maybe PO was my Brother in law. He is like that. Always busting bolds and screws out. What a Maroon.

[AlanB]

Hi Guys,

Problem is often ill-fitting tools and lack of concentration!

If it seems tight, don't pull on it until you break it; try some lube, p'raps a bit of heat, maybe a tap with a hammer to loosen the crud in the thread; and DON'T GET ANGRY!

AlanB

[Crazcnuk]

I've never seen a 'tight' mixture screw....

THese screws never have any business being tight, they are always somewhere in the middle with only spring pressure on them.

Even if you were a complete idiot and tightened it in until it bottomed and then gave it enough to take the tighten side of the slot out, you should still be able to back it out?

To destroy both sides of the slot takes real talent.

[81xsproject]

They don't have to be tightened to be tight. Mine were not bottomed out, but frozen from years of not ever being turned.

[AlanB]

Hi Guys,

I have had to un-seize a few; if that little tunnel gets water down it on a bike which is not being warmed up, they can get very stuck!

AlanB

[Crazcnuk]

Hmmm, makes one wish he had caps for those holes!

[AlanB]

Hi Cnuk,

It is only really a problem if the bike is sitting unused for yeas; if it is being warmed up regularly, they are usually OK!

AlanB