Author Topic: carb issues  (Read 2414 times)

dex3703

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carb issues
« on: June 21, 2004, 01:45:47 PM »
hi folks,

I got the new rebuild kits from Keyster and have cleaned and replaced all the parts. Unfortunately I also replaced what I guess is the main mix screw (there's a new one in the kit), and now the mix will be all off.

How do I set these initially? What's the process for getting the mix straight? I've never rebuilt carbs this complicated before.

I also have a totally unrelated problem with my car and a frozen bolt/screw. It's a phillips that holds the ignition rotor on and it won't come off. Have used bolt breaker stuff (had to use a lot of this on the carbs!) but no dice. Suggestions?

Thanks,
Derek

Jon

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Re: carb issues
« Reply #1 on: June 21, 2004, 01:59:11 PM »
Turning thhose mixture screw 4.5 turns out each seems to be the most common setting.  The front cylinder might work well with 2.5 - 4.5, though.
Try a pair of vice grips on that bolt.  If you must, close the vice grip with another clamp for extra gripping power.  Hasn't failed me yet.

dex3703

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Re: carb issues
« Reply #2 on: June 21, 2004, 02:10:55 PM »
Thanks. So to clarify, turn them all the way in, then out that amount?

I'd use the vise grips on the frozen screw except there's no room to get in there. I did that for the carbs, though.

Thanks!

Derek

h2olawyer

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Re: carb issues
« Reply #3 on: June 21, 2004, 02:25:12 PM »
When you turn your mixture screws in, don't turn them until tight.  Go slowly & you'll feel them bottom out.  Stop @ that point and then count your turns out.  As Jon said - 4.5 turns for rear carb and 2.5 - 4.5 turns for front.  This is a starting point and you will need to fine tune them after getting it started.  You will also need to synchronize your carbs to get full, smooth operation.

As for removing the stubborn screw - are you using PBlaster?  That stuff is amazing.  I was a firm believer in Liquid Wrench until told about this stuff right here on this forum.  Other things to try are impact driver & / or heat on the screw.
If you have an accident on a motorcycle, it's always your fault. Tough call, but it has to be that way. You're in the right, and dead -on a bike. The principle is not to have any accident. If you're involved in an an accident, it's because you did not anticipate. Then, by default, you failed.

wolfman

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Re: carb issues
« Reply #4 on: June 21, 2004, 06:06:06 PM »
Did the sync mixture thing today.  What I can tell you is that the 4.5 turns out is a good starting point but seems to err on the lean side.  With the manometer installed and at idle speed (1300-1500 rpm) turning the front carb screw has little affect until nearly all the way out or in at which point the idle speed and quality and manometer columns drastically change.  Turning the rear carb screw gradually in or out has a much more gradual affect.  This may be due in part to the fact that my YICS canister has an internal (front to rear) leak, so I think that may affect any attempt to adjust teh mixture precisely.  I'll try again with a new (used) intact or repaired YICS canister and repost if things improve.  My idle mix seems quite rich at the moment and the idle quality is "lopey"  some tweaking is yet to be done me thinks.

Derek

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Re: carb issues
« Reply #5 on: June 21, 2004, 09:30:10 PM »
Thanks for the info. I'll hopefully get this going tomorrow.

Yes, I'm using PBlaster. Unfortunately no dice as ofyet on my car.

Is there any particlar cleaning solution you're supposed to dip the carbs in? I could'nt find anything that wouldn't eat the plastic parts, so I just sprayed them with carb cleaner and brushed the inside chambers with an old toothbrush.

Derek

wolfman

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Re: carb issues
« Reply #6 on: June 21, 2004, 09:40:26 PM »
The Vision resource site (Lucky's site) linked to on the Riders of Vision home page has some very good carb instructions. ?Though Lucky may crucify me for this, I had very good luck just using a spray can of carb cleaner with the little red tube stuffed in the nozzle just spraying it through the various jets and passages and then spraying sloshing and brushing/rincing out the bowls. ?Pretty much spray it through every place you see a hole that a screw does not go into with special attention paid to where the fuel lines and vacuum lines attach. ?Clean the bowls with the boal drain screws completely removed so all the crud will run out through the drain passages. ?A sewing needle can be used (CAREFULLY!) ?to open up a clogged accelerator nozzle. ?Likewise remove the 4 screws holding the accelerator pump to the carb and spray out the passages under the rubber diaphram in BOTH directions until clear. ?When dealing with carbs that need hard to find and expensive parts (like our Visions) I prefer to do as little dis and reassembly work as possible...less chance of breaking something and being up the proverbial creek IMHO.
« Last Edit: June 21, 2004, 09:40:56 PM by wolfman »

Lucky

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Re: carb issues
« Reply #7 on: June 21, 2004, 10:09:14 PM »
I don't mind if you use carb cleaner spray to clean out your carbs.  if their not in bad shape that's fine.  if, however, they have sat more than a season or 2, then they will need to be dipped. most of the dried varnished gas will come off with the spray, but fresh gas & vibration will cause more varnish to flake off in the carbs, and you'll be continually tearing them down to clean them out.  better to do it right the first time, and save frustration & time.

Also, a sewing needle is too thick & stiff to clean out the accelerator nozzles. use ONE strand of picture hanging wire.
--Lucky
1982/3 XZ550 Touring Vison, Gold on Black

S Y

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Re: carb issues
« Reply #8 on: June 21, 2004, 11:52:33 PM »
Tuning an 82 visions carbs is a trial and error experience without the proper equipment. I use my old carb sticks (mercury manometer) and a Heath Kit CO exhaust gas analyzer. When synching the carbs try to keep the manometer mercuy level high by adjusting the throttle stop and then adjusting the mixture screws to keep an acceptable idle. I think the idea is to keep high air velocity through the carbs so the fuel and air jets work correctly during idle and low rpm running. Adjust the mixture screws a quarter turn at a time on one carb until the idle increases slightly and the fuel mixtures richens. Then do the same to the other carb. Adjust both carbs until fuel mixture and idle are correct (about 3-4% CO on my bike). You can do this without the gas analyzer, but there will be alot more trial and error.

Good luck and always check for air leaks at the venturi securing screws and make sure there is a washer and O-ring on the end of the mixture screws or you will never get the bike to run right at idle and or low rpm (surging).

Derek

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Re: carb issues
« Reply #9 on: June 22, 2004, 11:07:31 AM »
Thanks for the tips.

Now i'm going to look like a complete neophyte, but what order to the washer, gasket and spring go on the mix screws? There's nothing in the manual about this, besides a warning not to mess with this screw. :) The screws that were in it didn't have a washer so mabye that will make a difference.

Thanks,
Derek

nvdranger

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Re: carb issues
« Reply #10 on: June 22, 2004, 12:25:28 PM »
I have already built mine once with Lowe's o-rings and homemade overflow drains ::).  Got the Keyster Kits and installed them the other day, bike seems to idle alot better with the new kits vs the old jets (which doesn't surprise me but sure glad you guys got these kits going ;D).  Now if my darn stator would come in so I can ride it.
Anyways, back to your question.  The tiny o-ring goes in first and then the tiny washer, make sure both are sitting flat.  Then in goes the spring and finally the screw.

Ken
'82 Vision project.  First Vision, First Bike.
Sometimes monkeys die, Sometimes monkeys die.  It not a good saying, but its a saying.

Derek

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Re: carb issues
« Reply #11 on: June 22, 2004, 04:08:20 PM »
Ok. So it will look kinda like this:

--==[]|///////{}

[] o ring
| washer
////// spring
{} screw head

Thanks,
Derek

Lucky

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Re: carb issues
« Reply #12 on: June 22, 2004, 05:34:53 PM »
neat art work, lol
you have the order right
--Lucky
1982/3 XZ550 Touring Vison, Gold on Black

nvdranger

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Re: carb issues
« Reply #13 on: June 22, 2004, 06:04:23 PM »
:o wow that looks just like the ones i put in the other day.  great job/very creative

Ken
'82 Vision project.  First Vision, First Bike.
Sometimes monkeys die, Sometimes monkeys die.  It not a good saying, but its a saying.

Rick G

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Re: carb issues
« Reply #14 on: June 22, 2004, 10:24:47 PM »
The old oring is probably stuck in the bottom of the hole . Use a strong light  and a jewelers loop to see it . I  have a Piece of  piano wire with a small hook bent on the end  to fish them out.
Rick G
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