emergency. info to order new pilot screw for VM carbs?

[AOD]

i just noticed when i was counting out the turns on my fuel pilot screw for my 79 GS550, that i broke one of the tips off.

can anyone help me find this part? i am looking at carb kits for 77-79 bikes and it only has the idle air screw, no pilot screw!

i'm feeling totally SCREWED myself! argh!

~Adam

 

[frosty5011]

http://www.siriusconinc.com/carb/carb.asp?npage=1&lpage=4&id=3&curp=&trec=8

These guys should have them stock. I don't know which kit is for your year, you'd probably have to give them a call. But I believe these kits contain everything except for the emulsion tube. I just got one for my '79 GS750. Has all the needles in it. Was $15.00.

 

[AOD]

Ron i saw this the other day and it confused me...

first kit here says for 77-79:

notice it has no pilot screw.

second kit here says GS550:

it does have the pilot screw...so i guess i'm gonna order it up and pray.

8O

~Adam

 

[Don Lobacz]

Did you remove the broken tip from your carbs?

 

[hoyterb]

AOD Send me your mail address and I'll send you one.I have a couple extras and I'll give you one. hoyterb@hotmail.com

 

[AOD]

dang hoyer...i went ahead last night and ordered two kits. its okay really...cuz it'd be nice to have some spare o-rings or needles laying around just in case. i had just sold some extra points and condensors i had laying around, so i had the money for the kits.

thanks for the offer though, most generous!

~Adam

 

[redliner1973]

I noticed the part numbers are different, ones a #240 and the other is a 250# , but both are for same bike....m ay have to order it by the part # also. :twisted:

 

[frosty5011]

Adam,

I would've given them a quick call, just to make sure, and avoid any misunderstandings. Even though you placed the order yesterday, they may not have shipped your order out yet.

 

[AOD]

my reasoning that it will be okay is that it has to be for a 77-79 550 even if its not marked. Why? because 80+ CV carbs didn't have a pilot fuel screw on the bottom...so the kit wouldn't have it in there.

i'll email hoyer and see if he can put one in the mail for me, just in case the kit is wrong.

thanks guys,

~Adam

 

[KEITH KRAUSE]

Like Don Labacz said earlier, is the tip of the broken pilot screw still in the carb? If it is, you're gonna have a lean running carb at idle/lower speeds.

 

[AOD]

how do i get it out? i turned the carbs upside down and smacked them...nothing came out.

i thought the tip originally didn't break...and it fell off later when i was cleaning and putting them back together. i coulda swore when i took the pilot screws out, i didn't see any broken ones. 8O

if it did break off in there when i disasssembled first, then it may have gotten freed when i cleaned the carbs out with carb cleaner. i had them all apart and sprayed each passage and chamber a good amount.

to add to the fun, i'm not sure which carb the screw broke in...but now that i'm thinking about it, one of three pilot screws i've put in so far didn't screw down as far as the other two. maybe that's because the tip is in there!

oooh. oooh.

how do i get it out?! 8O

~Adam

 

[frosty5011]

Adam,

If the tip broke off, there's a good chance you could see it while looking down the throat of the carb. On my VM26 carbs, if I screw the fuel pilot in all the way (softly), close to 1mm of the tip shows poking out of the little hole in the carb throat (that's using brand-new, very pointed fuel pilot screws).

If you can't see it, and still want to make sure there is nothing blocking the passage(s), get some fishing line.......or pull a strand/bristle out of a whisk-broom. Remove the fuel pilots, and use your "non-destructive orifice checking tool" to make sure the passage is clear. You should be able to stick it in the opening in the carb mouth, and pull it out of the threaded fuel pilot screw opening. Or actually, with some decent light, you should really be able to look through the bottom pilot screw opening on the carb. Shine light through the carb throat with a flashlight, and check to see if you are able to see light through the hole.

 

[AOD]

i'll 'examine' down the hole with a 'probe' and a flashlight (if i can find one) tonight.

if the one tip is still in there, will it poke out easily, or is it going to be jammed in there like a mofo?

and to make sure i understand this right, if i look into the carb opening/bore i will see the tip stick up a bit if they are screwed all the way in?

~Adam

 

[frosty5011]

and to make sure i understand this right, if i look into the carb opening/bore i will see the tip stick up a bit if they are screwed all the way in?

On mine (VM26), yes.......I would assume you should also be able to.

 

[KEITH KRAUSE]

i'll 'examine' down the hole with a 'probe' and a flashlight (if i can find one) tonight.

if the one tip is still in there, will it poke out easily, or is it going to be jammed in there like a mofo?

and to make sure i understand this right, if i look into the carb opening/bore i will see the tip stick up a bit if they are screwed all the way in?

~Adam

To find out if a hole is blocked, it's very easy to just spray some carb spray or WD40 up into where the pilot screw was. You will be able to see the spray come up and out the hole. As for looking for a tip sticking out of each hole when the screws are seated, that does sometimes happen. But sometimes the tips do not come out. Believe it or not, the screws are not always the same length. This is something I discovered on my set of carbs and a set from a salvage yard. The spray test will tell you or the light will work too. It may be difficult to remove the tip without damaging the hole. You would need something very thin but still stiff. And because the tip is tapered you will have to push it back in. You may be able to take a strand of wire from a wire brush and using some needle nosed pliers, poke the tip back down. But it's a very small hole and because it's a soft metal, it will be easy to damage it. You may have to find another carb body. If you do have to get another body, make sure it has 2 holes leading to the throat for the pilot circuit. 1 is the main orifice and 1 is the pilot hole we've been talking about. Because of emissions laws, carbs assembled after Sep.'78 had only 1 hole and the pilot hole was capped by the factory.The carbs with only 1 hole will also have blunt tipped pilot screws, not sharp tipped screws. My brand new '79 1000 came with carbs assembled before Sep.'78. But other '79's were fitted with the 'later' carbs and tuned to accept these leaner carbs. I'm sure that 750's and 550's are involved in this too.These 'later' carbs will make your bike run lean at idle/ lower speeds. I wasted many hours trying to re-jet a bike that had these later carbs before I found the problem. No matter what size pilots you use, etc, you'll never properly jet the leaner carbs. This makes it a gamble to buy a set from E-bay, because you cannot check them personally. Unless the seller knows how to check for you.

 

[AOD]

lets hope its not plugged and/or i can get the tip out of there...else i'm screwed.

 

[AOD]

well...just as i guessed, the tip is broke off into the carb body.

i'm well more then screwed...nothing will get it to budge out. i can stick a straightened paper clip down the back side and move around the tip a bit, but nothing i stick in small hole inside the throttle body works. i tried brush brissles, a staple, pushpin, straightened spring...nothing

i hate carbs.

 

[KEITH KRAUSE]

That's a bummer. Which # carb is it, as they mount on the bike? Maybe someone here has an extra. I'd post a topic for it. Remember what I said about the pilot circuit having 2 holes. Do you have a salvage yard nearby?

 

[AOD]

there's a salvage yard somewhere in Wisconsin a few hours from here. :x

so what's the worst that can happen if i leave the tip broke off in there? it will run lean at idle? what if i idle at 2500 RPM - wouldnt it be running off the needle by then?

i have a set of carbs on my 78 GS550 that i was going to sell. they were cleaned by me last year, and run rich, but they run. i didn't replace any o-rings when i serviced them, but they seemed to work okay. if worse comes to worse, i can remove those carbs this weekend, since i planned to get the bike then anyway, and try them in place if the current carbs if the stuck pilot screw doesnt work.

i think i've got three options, because i'm doubting i can find ONE carb to replace the #2 or #3 carb. option 1, see if using a small drill bit to drill out the backside of the stuck pilot screw helps free it. or option 2, use it as is. option 3, use my other carbs.

what would you do?

~Adam

 

[KEITH KRAUSE]

Don't try to drill out the tip, it will ruin the hole and the bike will run MUCH worse. If you use the carbs off the other bike, it sounds like you will have more jetting problems and then not be able to sell the other bike as easily or you'll have to sell for less. I would try to find another carb body or a set. The bad carb will effect the idle and speeds up to about 60 and you'll have a lean condition and warm-ups will be rougher. What # carb was it? Try asking someone here for a spare for cheap.