Chaharly Posted March 26, 2015 #1 Posted March 26, 2015 Hey guys, I think I have a stuck pilot screw, I think It may be bottomed out into the carb. I can get a good hold on it to turn it right, but not to turn it left. Now being that brass is a soft metal, would it be possible to sharpen a screw driver, and lightly tap it into the brass to make the notch deeper? I'm not too terribly excited about trying to drill it out, and I have thought about getting a left hand drill bit, but I want to try some other ways first. On this thread from awhile ago I saw someone actually removed part of the carb and used a dremel to make a new and deeper knotch for the screwdriver to set in. Thinking about doing that, heres the link http://www.venturerider.org/forum/general-tech-talk/88384-stuck-pilot-adj-screws.html So now I'm looking for Ideas, so if any of you guys have them, let er rip! Thanks again -CJ
rbig1 Posted March 26, 2015 #2 Posted March 26, 2015 well if you look down the carb bore. Can you see the needle sticking in there. if you can you can cut the body like they did in the pic. I smoothed off the cut more and found it was 1/4 inch past the base of tube. Two of them I never got loose but the other came loose with warm oil and time. Good luck
Marcarl Posted March 26, 2015 #3 Posted March 26, 2015 When I did mine, I drilled it out, went fairly easily actually. First I got a drill bit that was just undersized for the bore. It might have a metric bit, but it has to be real close to the size of the bore so that when you drill the point ends up dead centre of the screw. I then drilled slowly and carefully to remove the buggered up head of the screw and to give a centering dip on the end of the brass screw. Then I switched to a much smaller sized bit, one that would give me a nice pilot hole through the screw but not to touch the threads. Then it was the next size up to a size very close to the bore size through the thread. When that was complete there was nothing but clean threads left. A little use of a tap and all was good. Keep in mind that the threads don't start at the top of the bore, they start about half way down so that makes it bit easier. Just be careful not to get into the threads.
Chaharly Posted March 26, 2015 Author #4 Posted March 26, 2015 Thanks for the advice guys, I think I'm going to try the torx bit method first. Then I'll work on drilling it if need be. If I can get it backed out far enough to work properly that will make me happy. So when you drilled it out and tapped it I assume you had to replace the screw. Where did you get yours from?
Chaharly Posted March 26, 2015 Author #5 Posted March 26, 2015 Just called the dealership and found out they have a jet in stock for 8 bucks
BlueSky Posted March 26, 2015 #6 Posted March 26, 2015 Have you tried an impact driver? Every motorcycle owner should have one of those miracle devices!
dingy Posted March 26, 2015 #7 Posted March 26, 2015 Have you tried an impact driver? Every motorcycle owner should have one of those miracle devices! Bill, Your profile shows you are an engineer, what field of engineering? Gary
Chaharly Posted March 26, 2015 Author #8 Posted March 26, 2015 Have you tried an impact driver? Every motorcycle owner should have one of those miracle devices! I haven't yet, but I think the head is too damaged to get a grip
dingy Posted March 26, 2015 #9 Posted March 26, 2015 I haven't yet, but I think the head is too damaged to get a grip DO NOT even think about using an impact driver on the pilot screw, PLEASE !!!!! Gary
Prairiehammer Posted March 26, 2015 #10 Posted March 26, 2015 DO NOT even think about using an impact driver on the pilot screw, PLEASE !!!!! Gary I will agree. The fine brass threads of the pilot mixture screw, nor the fine aluminum threads in the carb body, probably will not withstand the stress of a hammer impact driver.
Marcarl Posted March 27, 2015 #11 Posted March 27, 2015 Looks like you have answered my question already. And OH, don't use an impact driver,,or even a hammer!!!!
BlueSky Posted March 27, 2015 #12 Posted March 27, 2015 If it is indeed stuck, I think I would try lightly tapping on it with an impact driver. You don't have to use a BFH. Yes Dingy, I have a BS in chem eng. All of my work experience has been working in a mechanical engineering job at nuclear power plants, usually as a Mech Design Engineer, sometimes as a Project Manager, or Project Engineer. My first job was startup and test engineer checking out and getting the systems to work and running properational tests on the equipment at the Brunswick Nuclear Power Plant. Prior to getting my degree, I spent a tour in the US Army where I went to school for 40 weeks to learn how to repair the target tracking, target ranging, and missile tracking radars for the Nike Hercules Missile System. I also repaired the analog computer that received information from all 3 radars and guided the missile to its target. Got to spend about 16 months in South Korea on a missile site way out in the middle of the rice paddies. The Army experience has served me well in my career.
Du-Rron Posted March 27, 2015 #13 Posted March 27, 2015 Before you take an impact driver, drill, blowtorch, or gun powder to it, try some penetrating oil in it. Leave the oil in the hole for about 1/2 hour and then work it back and forth for a while. Nothing -Ventured- nothing gained. (I crack myself up sometimes...)
venturesome Posted March 27, 2015 #14 Posted March 27, 2015 Can someone explain to me how an impact driver works? I'm getting confused. I thought you had to hit it pretty hard just to get it to turn.
Du-Rron Posted March 27, 2015 #15 Posted March 27, 2015 Can someone explain to me how an impact driver works? I'm getting confused. I thought you had to hit it pretty hard just to get it to turn. When you hit it and glance off the top and hit your hand instead it makes an impact after you throw it at the wall. No, the tang is against a ramp. Even a small tap will transfer downward and a little torque force as you twist it by hand. Yes, the harder you hit the more torque is transferred. Right about the point you think you have it loose, the lever mysteriously flips to the other side. After 3 or 4 blows you realize that you are now again tightening the thing. Once again it makes that "impact" sound after you throw it against the wall. On the manual side is impact screwdrivers that have full length tang with a metal head on the top of the handle. The only torque force there is by you twisting it. Downward force is by you hitting it. Call this the "delicate" version of an impact driver.
Brenner Posted March 27, 2015 #16 Posted March 27, 2015 When you hit it and glance off the top and hit your hand instead it makes an impact after you throw it at the wall. No, the tang is against a ramp. Even a small tap will transfer downward and a little torque force as you twist it by hand. Yes, the harder you hit the more torque is transferred. Right about the point you think you have it loose, the lever mysteriously flips to the other side. After 3 or 4 blows you realize that you are now again tightening the thing. Once again it makes that "impact" sound after you throw it against the wall. On the manual side is impact screwdrivers that have full length tang with a metal head on the top of the handle. The only torque force there is by you twisting it. Downward force is by you hitting it. Call this the "delicate" version of an impact driver. So you delicately throw it at the wall to get that delicate impact sound? LOL I only love this as I fully understand your point. I have seen so many people do greater damage trying to use impact drivers and yes my hands have experienced the effects of glancing off the top and usually when heavily driving to attempt to remove a large screw. As far as removing the pilot screw I find that stretching the threads has worked for me many times and I usually regret it if I don't try that first. Just remember that brass is soft. I have done this on my own project with success.
Chaharly Posted March 27, 2015 Author #17 Posted March 27, 2015 So I got my plan, I'm going to hit the little bastard with my BFH!
Venturous Randy Posted March 27, 2015 #18 Posted March 27, 2015 This is an old post on what worked for me. Randy http://www.venturerider.org/forum/general-tech-talk/1946-stuck-air-mixture-screw.html?highlight=drilled
videoarizona Posted March 27, 2015 #19 Posted March 27, 2015 Maybe this? 980 Series | Impact | Screwdrivers | Hand Tools | VESSEL TOOLS
Du-Rron Posted March 28, 2015 #20 Posted March 28, 2015 Maybe this? 980 Series | Impact | Screwdrivers | Hand Tools | VESSEL TOOLS Those are good. But I was thinking of just the full tang screwdriver for light duty work like so... These have no springy guts in them and have a metal striking cap on them. They are for a more "delicate" touch.
Du-Rron Posted March 28, 2015 #21 Posted March 28, 2015 Pilot Jet Removal Tools: These are the factory authorized Pilot Jet Removal Tools. Immediate results Guar-Ron-Teed. (Also resizes pilot from wimpy #15 to a full manly 0.250")
videoarizona Posted March 28, 2015 #22 Posted March 28, 2015 Those are good. But I was thinking of just the full tang screwdriver for light duty work like so... [ATTACH=CONFIG]98396[/ATTACH] These have no springy guts in them and have a metal striking cap on them. They are for a more "delicate" touch. As long as they are JIS screwdrivers...that would work to.
Chaharly Posted March 29, 2015 Author #23 Posted March 29, 2015 When I did mine, I drilled it out, went fairly easily actually. First I got a drill bit that was just undersized for the bore. It might have a metric bit, but it has to be real close to the size of the bore so that when you drill the point ends up dead centre of the screw. I then drilled slowly and carefully to remove the buggered up head of the screw and to give a centering dip on the end of the brass screw. Then I switched to a much smaller sized bit, one that would give me a nice pilot hole through the screw but not to touch the threads. Then it was the next size up to a size very close to the bore size through the thread. When that was complete there was nothing but clean threads left. A little use of a tap and all was good. Keep in mind that the threads don't start at the top of the bore, they start about half way down so that makes it bit easier. Just be careful not to get into the threads. Ok I got the head off! Now how do I get the guts out?
Marcarl Posted March 29, 2015 #24 Posted March 29, 2015 Ok I got the head off! Now how do I get the guts out? If you did it carefully and used a drill the just fit the bore you should have a dip in the centre of the screw that will guide a super small bit into the centre of the screw. I would suggest to start with a 1\16 bit, and work a little at a time. Slowly, carefully drill the brass out of there, careful not to go past the threaded part or you'll end up buggering up the pilot hole. Drill a fes rounds, blow it out, check it, drill a few more rounds. Once you get through the threads the rest will fall out, no need for a bit down that far. If everything is still in place with the 1\16 bit, go the next size up,,,,,,, and oh,,, don't use a dull bit.
Prairiehammer Posted March 29, 2015 #25 Posted March 29, 2015 Here is a picture of the pilot screw. It may help you visualize what Marcarl is explaining.
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