I done broked my pilot adjusting pointy end!!!

Well, on my 1978 kz1000 A2 stock carbs, which I had taken off the bike for cleaning, I over-tightened the pilot adjusting screw so much that, when I realized I'd screwed it in too far (because the shiny, brass pointy end of it was STICKING UP through the mouth of the carb on the engine side of the carb) I said "whoops, I screwed in the pilot too far" then started backing it out.

And since it's a brass screw, I guess (?) the pointy tip of it broke off and WAS STUCK in the little hole there in the mouth of the carb on the engine side. I had the Pilot screw completely removed and yet its little brass tip was still visible in the mouth of the carb. Sh*t!!! Visions of searching on eBay for a used bank of kz1000 carbs roared through my tiny little pea brain.

Luckily, the little pointy brass tip came completely out of the carb when I tapped on it.

But now my Pilot screw is missing its pointy tip.

WHAT WILL THIS DO TO THE IDLE RUNNING OF THE MOTOR?



(ps. reason I screwed in the Pilot adjusting screw was to first seat it in the 'all the way closed' position then back it out the standard 2 1/2 turns.)

Can you post a pic? I have a rack of trashed carbs that might have what you need but I need a pic to see

My question could be more clear.....here goes.


See, I don't want to have to order a new pilot adjusting screw. See the picture of my carbs during the cleaning below -- in the picture I'm holding the Pilot Adjusting Screw with my needlenose plier.



This is *before* I broke the pointy tip off.

I want to continue to use this Pilot Adjusting Screw despite its broken tip because--
well, because (1) I'm cheap (2) I already waited a week
to get parts (o-rings) to finish the carb job, I now
have them in my hands, I don't feel like waiting another week for a new Pilot Adjusting Screw, and (3) I'm quite suspicious that my #2 carb will not very much miss that little tip off the Pilot Adjusting Screw.

AM I RIGHT?

By over-tightening the pilot screw, you have enlarged the hole in the aluminum. This will now totally screw up the adjustment in relationship to the other three carburetors. The needle is no problem. one comes in every carburetor rebuild kit. There are two things you can do; 1) replace that throttle body, 2) adjust each carburetor individually by ear or tach at idle. The second option is much cheaper, but requires some skill, and experience.

otakar wrote:

By over-tightening the pilot screw, you have enlarged the hole in the aluminum. This will now totally screw up the adjustment in relationship to the other three carburetors. The needle is no problem. one comes in every carburetor rebuild kit. There are two things you can do; 1) replace that throttle body, 2) adjust each carburetor individually by ear or tach at idle. The second option is much cheaper, but requires some skill, and experience.

I'm sorry for mixing words -- I have edited my post to be consistent.

There is a 'pilot jet' in each carb -- which I'm not talking about at all.

There is, in each carb, a part called:
"16014-018 SCREW,PILOT ADJUSTING"

THAT is what I'm referring too. I corrected my post to be consistent in my verbiage.

I take your point -- I may have to deal with a different adjustment for this carb whose Pilot Adjusting Screw I overtightened.

What should I expect when I start the motor? I mean, should I expect that at idle and the very start of opening the throttle, that this one cylinder won't be firing or something?

newOld_kz1000 wrote:

otakar wrote:

By over-tightening the pilot screw, you have enlarged the hole in the aluminum. This will now totally screw up the adjustment in relationship to the other three carburetors. The needle is no problem. one comes in every carburetor rebuild kit. There are two things you can do; 1) replace that throttle body, 2) adjust each carburetor individually by ear or tach at idle. The second option is much cheaper, but requires some skill, and experience.

I'm sorry for mixing words -- I have edited my post to be consistent.

There is a 'pilot jet' in each carb -- which I'm not talking about at all.

There is, in each carb, a part called:
"16014-018 SCREW,PILOT ADJUSTING"

THAT is what I'm referring too. I corrected my post to be consistent in my verbiage.

I take your point -- I may have to deal with a different adjustment for this carb whose Pilot Adjusting Screw I overtightened.

What should I expect when I start the motor? I mean, should I expect that at idle and the very start of opening the throttle, that this one cylinder won't be firing or something?

the broken tip might be your biggest problem, not the fact that you might have bored out the hole it screws into a little....that tip is there for a reason...i m guessing you are gonna have a little difficulty dialing in that one carb...it s gonna be all or nothing as far as
an adjustment.....just my guess....hell, put em back on and see what ya get....i think i have another pilot screw
you can have.....let me know....

i knew exactly what you were referring to. The needle only affects the idle nothing els. i believe that on this particular carburetor, this is a fuel screw. If it was on the side it would be an air screw. This means that if you adjust the screw according to the book the engine will be rich at idle.

Even if you did enlarge the hole in the carb it can be compensated for by screw adjustment. The trouble with the pilot screws is the steep taper is easy to misjudge when it seats lightly and easy to bend the tip and also break off. You'll need a new pilot screw I'm afraid at $20 or more otherwise you'll be way rich in that cylinder.

No eBay APP ID and/or Cert ID defined in Kunena configurationYou will have to redo the carbs anyways since they are such a mess so just get these kits and do all four. You will get all the new parts you will require.

Agree w/Oct, The tip of your' aduster screw was the controling bit which regulated the fine tuning of the pilot circuit at idle. and while commonly addressed as a fuel screw, a more accurate term would be fuel mixture screw, since after the pilot jet this passage flows vaporized fuel, not raw gas. depending on how far down the taper your' screw broke, it may or may not have any limiting effect on this passage. at a guess, this screw has little effect at over 1/8 throttle. and even if it has no metering effect should only cause that cyl to be rich at idle, not cause immediate "dead cyl"... get a new screw. again screw all screws to light contact and compare exposed tips in throat. when damage has been done to seat, it's usually very difficult to remove broken bit and new screw exposes obvious difference in tip height. Even in new (plugged) carbs from factory differences as much as 1 full turn between cyls was common. the standard of screwing to contact then backing out a prescribed distance is simply a base for tuning/jetting, not a panacea. an ega of individual cyls is best, but a trained ear can get pretty close. luck, G

keith1 wrote:

the broken tip might be your biggest problem, not the fact that you might have bored out the hole it screws into a little....that tip is there for a reason...i m guessing you are gonna have a little difficulty dialing in that one carb...it s gonna be all or nothing as far as
an adjustment.....just my guess....hell, put em back on and see what ya get....i think i have another pilot screw
you can have.....let me know....

Thanks for your encouragement, I think I will put on the carbs, and just be prepared for some challenge to get the one carb so it's not affecting the just-off-idle or the actual idle.

otakar wrote:

i knew exactly what you were referring to. The needle only affects the idle nothing else. i believe that on this particular carburetor, this is a fuel screw. If it was on the side it would be an air screw. This means that if you adjust the screw according to the book the engine will be rich at idle.

Okay, thanks for being knowledgeable, I have a question -- I looked high and low in my Kawasaki shop manual (the official one from the manufacturer, not a Clymer) and all I found for adjusting this Pilot Adjustment Screw was on page 47, bottom right:

"...turn in the Pilot screw fully, but not tightly, and then back it out the number of turns counted during disassembly."

Well there's 3 things wrong with that:
1) doesn't even give a rough guidance like "usually 1 1/2 turns out should be sufficient"

2) 'fully but not tightly' sorry there whats the difference (duh the difference is I broke the tip off)

3) 'counted during disassembly' -- what if you're some type of rabid idjit and you *assume* there is a 'rough guide' as in (1) above....so you never bothered to be careful and count the number of turns out and write it down

I vaguely recall about 2 1/2 turns out but not sure.

My question is, do you have a rough starting point for the number of turns out from the 'fully in' position for these Pilot Adjustment screws on stock carbs for this kz1000 '78? Is there somewhere in the kz1000 official shop manual, such as a table or description that I have not stumbled across yet?