Need 90's PhazerII Carb diagnosis

[DallanC]

Ok so we had a huge storm blow through (3-4ft powder!) so I took the famility up for a ride to the local snowmobiling spot, figuring friday would be a good day due to few people. It was fun. However my PhazerII developed a problem about early on in our ride.

Basically just off idle up to about quarter throttle when riding on a trail the engine would bog quite a bit. If I got the RPMs up and got her at half throttle on up to wide open it ran great. If I stopped it would die and not restart. If I got it restarted it would idle ok.

Initially I was absolutely convinced it was flooding out. I pulled the plugs to air it out and saw they were bone dry... wha? When I tried restarting, the only way I could get it to fire up was with the choke set half on, and it fired right up (this with a hot engine... after riding for 30 min). This made it a pain in the *** to launch in deep powder after getting stuck as it kept bogging going from idle to half or open, again it felt like it was flooding but the reverse is true, its not getting fuel?

Ideas? I'm going to pull the carbs off later today and try and clean them. Could it be a plugged jet or something?

PS: I'm now totally convinced I need a new sled... saw a couple new XP's, couple new Dragons and a new M1000 up there, its just insane how much better the new stuff is than the older dinosaurs. But I still saw pretty much each of the new sleds get uber stuck in the soft powder so I didnt feel totally outclassed LOL.


-DallanC

 

[Kootenay-Stomper]

check the reeds,mite have eat a couple?

 

[wwracer]

Seeing as it starts with choke(seperate circuit) half on you probably have ice/water or junk around the main jet. My kids used to do the same. Drained tank new lines and disassembled and cleaned carbs with compressed air. Two seasons of riding now with no issues. Easy carbs to work with, just don't drop noth'n, as spare parts are absurdley expensive....

 

[Adrenaline Revolution]

I spent a lot of time with those darned carbs!
First off, disconnect the wires that come out of the carbs and plug them into each other (Sled side and the carb side) a lot of problems are solved by doing this.
You just need to plug the sled side back to itself to complete the "Loop". These are white and black striped wires.

My guess is that there is varnish plugging up the jets somewhat and just blasting some carb cleaner through all the passages will fix it.
Wipe out the bowls and clean all the varnish off of the floats and the needle and seats. Make sure the needle and seats work well before you put them back in. (they get gummed up sometime too and will not open).
Check your reeds while you have it apart for cracked or broken petals.

Good luck

 

[Viper5]

You might want to try gas line antifreeze first, use to need to carry that with all the time on my old PZ.

 

[vmaxfrank]

First, check compression to make sure rings haven't gone bad. My ZX has low compression and acts like that.

Then like others said, maybe gummed carbs or bad gas. Make sure to drain the gas and start new. Run some seafoam or other carb cleaner additive in when you put it back together.

If you get a new sled, don't turn loose of the Phazer. I have a Phazer II ST (136"X1.5") and my wife still likes it better than her ZX summit. They are a hoot as long as you don't need hill climbing power and the are super easy to get unstuck compared to newer sleds. Plus they make great kids sleds or loaner sleds. After all, I think they were one of the first 'mountain' sleds made.

 

[thefullmonte]

One of the little black plugs inside the carb may have come off?

 

[FEZ]

1) your pilot jets are plugged.
2) your main jets may be too
3) to the left of the gas door is a little panel, remove it and remove the screws, this will make removing the carbs MUCH EASIER!
4) These carbs are a bit of a pain to remove....
5) flip the carbs over before removing the bowls, there is enough cable length so you do not have to remove it.There are 2 black plastic plug like things and 3 holes inside. MAKE SURE you know which holes they go in. If you f-up 1 of them goes in the middle and if I remember right the other goes to the left of center

 

[DallanC]

First off thanks for all the advice everyone had.

I pulled the carbs (I'm getting faster at it LOL, its pretty easy if you take the boot off between carb and airbox, then you have plenty of room to get the carbs out). So anyway, I carefully disassembled the two carbs, being extremely careful to keep parts for the left carb in 1 spot, parts for the right carb in another spot so they could all return to their original locations (I noticed the main jets were different #'s so I put'em back in the original carbs).

One thing that struck me right off the bat is the little black plugs in 1 carb didnt match the other carbs configuration. Both carbs had one plug in the center, one carb had one in the left side (which seems to block an undrilled passage as per air gun test) and the right side was uncovered which had a jet in it. The other carb had the right jet plugged, leaving the left side open. I guessed this was incorrect and idly wondered how this affected the sled's performance over the years... ).

I carefully cleaned and blew out all of the jets and the carbs. There were a couple of things that looked plugged that i had to use a needle to pick junk out of before rinsing with carb cleaner and blowing out with an air gun. Once everything appeared good to go, I carefully re-assembled everything, checked the float levels and finished up. Stuck it all back on the sled with no problems and the sled fired right up after 2 pulls & a shot of ether. I felt confident the future was going to be much funner!

Well then we get to today. Its christmas eve, took the family ice fishing (had fun, caught a bunch). My 7 year old got the courage to take my wifes Phazer for a spin (out on a huge lake, nothing to run into... perfect place for a kid to learn to drive a sled ). Anywho I fired up my sled, it lights up like a champ, unload it from the trailer, get all the ice fishing gear ready (ie shack, auger) and hook it up to my sled for the short tow down onto the lake.

It starts off easily, the just after idle bog is gone! YAY! I head on down the hill and give it some more throttle and it bogs...! There is no mid range, no top range now. Return to idle and its fine, just off idle up to 1/3rd throttle and its fine... get rpms up around 3800 and thats it. Fook! I cant for the life of me think of anything I did wrong in the assembly of the carbs. I'm not a pro, but I've rebuilt a bunch of auto-engines, done a ton of auto carb jobs... re-ringed a couple phazer engines, tore down / rebuilt more motorcycle carbs than I care to remember... wtf is happening???

The *only* thing I really changed is unblocking the one right side jet in the 1 carb to match the other. Could that be it? I cant imagine there would be a reason to block off a carb port that has a jet behind it.

A Massive blizzard rolled in soon after I got home so i havent pulled the plugs yet to see if its a lean or rich condition... I *did* try hitting the choke while it was bogging to see if it increased or decreased RPMs, but it only made the bog slightly worse).

Oh yea one last thing, Adrenaline Revolution mentioned shorting out the switch to the carbs by plugging the male/female leads into each other where the carb leads plug in... what is the purpose of this? What is the purpose of the switch on the carbs anyway?

I'm pretty disappointed as you can imagine... Ideas?


-DallanC

 

[markoo]

If your using ether to start your sled I would start looking for a new motor soon.

 

[DValentine]

With the carbs sitting up side down, so that the throat facing the air box (the big one) is toward you, the plugs go in the center and left hole.

Had mine running yesterday for a few hot laps. Started loading up on one cylinder. Found the MJ was loose. Go back and check your work. Set the float at 12 mm. Make sure that the floats are not compressing the spring when you measure them. Lay the rack over on the side so that float is hanging when you measure.

Dave

 

[autowrench]

The electrical connnections are called TORS. It's a throttle safety system that keeps the sled from running away if the carbs stick open and you let off the throttle. At least, that's the way I understand it. I'm currently fiddling with another phaser that has a bogging problem. I think my problem might be caused by stripping the choke cable threads in the carb body. I have not sorted that out yet, but it is something to check. If I remember right, the plugs do go in the holes that have jets in them! Not to plug another site, but you might check totallyyamaha.com for a wealthe of phaser info.
Tom

 

[eddy]

Maybe the carbs are OK and the clutch has problems?

Primary clutch with worn out bushings?

 

[mountainbigbull]

Primary clutch with worn out bushings?

Good point maybe your barking up the wrong tree with the carbs.

Also I wonder if you are leaning out with bad crank seal(s)?

 

[DallanC]

Primary clutch with worn out bushings?

Good point maybe your barking up the wrong tree with the carbs.

Also I wonder if you are leaning out with bad crank seal(s)?

I doubt both of these cases just because other than the just off idle bog in the initial ride, it ran great and clutches seemed fine. When I cleaned out the carbs there was some grit in a couple jets so I think that accounted for the off idle bog. When I tore down the carbs I noticed the mis-matched configuration of the black plugs so I thought perhaps that was the problem after riding it the 2nd time.

I'm going to pull the carbs off again this week when I get time and go through them again. I did dig up the carb disassembly and cleaning section of my Phazer manuals and they indeed show the plugs do NOT cover the side jet. It covers the center hole and then the hole opposite the side jet... so I was correct in how I put them together.

Something else is obviously up though to loose the top end like I did. I cant imagine the seals would go that bad that fast to cause this problem after a day or two, nor that the clutch bushings are gone. I musta messed something else up in the re-assembly.

Thanks for the hints and suggestions. Side note. It seemed to be smoking more than normal... I wonder if perhaps the oil pump cable got pulled on and hasnt seated back into the adjuster... that could cause an extremely rich oil situation that would bog down at higher rpms.

/ponder


-DallanC