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Discussion Starter · #1 ·
Hello again, I have a 1984 yammaha phazer Special Edition. The sled has been sitting 2 years and we just took out the carburators and took them to a shop to be cleaned and we put fresh gas in. Now when starting the sled it olny runs on half choke and idles really high (3,500 rpms) and will go if you pin down the throttle at half choke then put it at no choke she will really go, but as soon as you let off it dies. We think its the idle adjustment? Anyone know anything about the old phazers? Whats wrong here?
 

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When you put the carbs back on, did you adjust the choke, air / fuel mixture screws? Sounds like they just need to be adjusted.
 

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Id take apart the carbs and completely clean them. It sounds like either you have a plugged jet or maybe a carb float that is sticking.
 

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Discussion Starter · #5 ·
The carbs were proffesionally stripped down and soaked in a shop, we just put them back in, and yes maybe the Fuel/air mixture screws may be messed with but we playerd with tme.
 

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The symptoms point to the intake system having an air leak and running lean. Do you have the airbox on? Is the black plastic crossover (boost bottle) correctly in place and not leaking?
Check that everything is tight and there are no intake leaks - rubber boots (they can crack), reed block gaskets, the small rubber caps on the barbed fittings on the carb flanges, etc.

It can be checked by spraying starting fluid around the carb area with the engine running. If the RPM increases, there is an air leak.
Remember that the ether can be drawn into the air box intake and cause an RPM increase. Hold the can close and spray in short bursts.
Having such a tightly packed intake system may make it hard to pinpont the leak.
 

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Turn in your pilot screws to (litely)seat,then back them out 1-1/4 to 1-1/2 turns. While it's running hold the throttle at about 1800 rpm,turn in your idle screw till it idles on it's own,you might have to set the idle on the second carb as well,and (could)interfere with the safety switch,make sure no choke plungers are sticking or out of ajustment,hope this helps a little, Phazer carbs are a bit finniky,but once there dialed in work fine.[8D]
 

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Originally posted by PZ1
[br]The symptoms point to the intake system having an air leak and running lean. Do you have the airbox on? Is the black plastic crossover (boost bottle) correctly in place and not leaking?
Check that everything is tight and there are no intake leaks - rubber boots (they can crack), reed block gaskets, the small rubber caps on the barbed fittings on the carb flanges, etc.

It can be checked by spraying starting fluid around the carb area with the engine running. If the RPM increases, there is an air leak.
Remember that the ether can be drawn into the air box intake and cause an RPM increase. Hold the can close and spray in short bursts.
Having such a tightly packed intake system may make it hard to pinpont the leak.
I think you are correct in your diagnosis but have a ? any of those leaks would have to be between the carb to the motor, or would a cracked boot between the airbox and the carb cause any trouble, ie: a lean condition?
 

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The boots I was referring to are between the carbs and motor. I think you are correct in that cracked air box boots probably would not make much difference.
The airbox does cause a restriction in air flow, but not much at idle speeds.

The high RPM's are what point to an air leak. Plugged jets or incorrect mixture settings would not normally cause that.
However the throttle plate/s being partially open because of an incorrectly set; throttle cable, idle speed setting, throttle synchronization setting, or a binding or blockage somewhere in the linkage combined with low fuel flow could do it.

.
 

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I agree with PZ1. It sure sounds like an air leak between the carbs and engine. Do what he suggests and also check to make sure the rubber intake boots did not fold in when you installed the carbs. They were notorious for doing that (usually on the bottom where you can't see them). I usually lubed the intake boot with a bit of oil to make it easier to install the carbs.
 

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Discussion Starter · #12 ·
We checked the box, the boots, all the fuel lines, we did what phazerboy said. We still cant figure it out, it idles fine on half choke but once choke is off it revs really high then dies.
 

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sounds like no fuel flow thro low end. ie pilot jet, or needle and seat. or the floats are not rising properly and not allowing enough fuel to pass thro
 

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One other thing to check, is the seal on the clutch side. I had that go out on my and it ran just as you described. you can shine a light down by the cluch without taking it off, if you see any amout of rubber hanging off then chances are the seal is week. also check to see if it's running on both sides. pull off one plug wire and try and fire it up. then the other. on mine it seemed to run on the mag side, but not the clutch side. hope that helps.
 

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I just went through this with a Phazer and Phazer II. If it's not an air leak it's the pilot jets. Take those pain in the butt carbs back off. Take the carb bowls off. Take a tiny screwdriver and pull those puppies out. Try and blow through them. I guarantee you can't. Spray them with carb cleaner, and use an old toothbrush. Push some bristles through it, and scrub it down. Spray it down again. Make sure all orifices are clear and clean. Re-insert and tighten. Put it back together and fire it up.

I know - they were professionally cleaned. I fixed a sled for a guy who just got his cleaned at a Yamaha dealer. And what did they do, since they said they were spotless? I don't know. Sprayed down the carb throats? I can tell you that they didn't even remove the carbs from the engine, let along the enricheners or slides.

I've never brought anything I've ever owned anywhere to get fixed. I don't trust them. Want it done right? Do it yourself.

Bryan
 
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