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Discussion Starter · #1 ·
My buddy has two sleds one vin starts with 88h so that's a 91. The other one starts with 87f so I'm not sure what year and I would like to know that too.

The 91 ran terrible, we cleaned the carbs an they were terribly dirty. Now she runs sweet. But when you giver all she's got, it takes off sweet and tons of power up to about 50. Then it just kinda stays there. Like it goes into tenth gear. Not much power. Like it's loading up.

Is this the clutch? And which one? Do I need to replace parts or can a good cleaning on the primary rollers and pins or what? I am real familiar with arctic cat mid nineties clutches, but don't know anything about yammy clutches.

Please help. Thanks!

I didn't read the forum policy real well when I signed up, can I post my cell number, so someone that knows can call?
 

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Discussion Starter · #3 ·
Clutches

Ok that's kinda what I figured. But what am I looking for? How do I know if a spring is weak?

Are the clutches pretty much the same as the comet clutches on a 94 arctic cat? Check for grime or flat spots on rollers and arms, too much slop, etc.?
 

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Mr. Budget Mechanic
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87F is a 1990 Phazer ll.

My '87 Phazer did pretty much the same thing, had plenty of low end pop but lacked top end punch and would top out at only about 50. With the rear end lifted on a stand and no load on it, the sled pulled hard up to about 5000 RPM, and then would hang and ever so slowly accelerate to about 6-6500 RPM and a top speed of only about 75 MPH. I experimented with different jettings (eventually settling on 125 mains and 95 pilots)-and most importantly-moved one of the rubber plugs in the float bowl so that it covers the pilot jet. What a huge difference it made! It now pulls hard throughout the whole throttle range and hits about 8300 RPM and 100+ MPH on the stand. I've had it up to 60 MPH on the snow and there is plenty of acceleration left. I estimate it should now do close to 80 MPH, and I weigh close to 200 Lbs. No clutch adjustments necessary.

I made the same adjustments for a buddy's '90 Phazer ll who was experiencing the same symptoms, and it fixed his sled too. Do a search on this forum and you'll find a ton of threads on this phenomenon. Apparently it's a pretty common problem with these sleds. They also seem to me to be pretty sensitive to altitude & temp changes, so getting the jetting right can be tricky. It doesn't help that the manual tells you to put the plugs in the wrong place also. I speculate that plugging off the pilot jet may be a high altitude adjustment and that the manual's instruction to leave the pilot jet unplugged might be fine if you ride at lower elevations, but I'm not sure about that. Even this parts fiche contradicts the manual plug placement however:Yamaha Snowmobile Parts 1990 PZ480P - PHAZER II CARBURETOR Diagram

Make sure you're jetted properly for your riding conditions (altitude & temp range), and that the black rubber plugs in the carb float bowls are in the proper place first. The manual appears to be wrong: it tells you to leave the pilot jet exposed; the pilot jet should be plugged (I know it doesn't seem to make any sense to plug the pilot jet, but it runs a helluva lot better that way, at least at high elevations).

Plugs should look like this:
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Not this:

[/IMG]

If that doesn't help, then check the clutches.
 

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Discussion Starter · #7 ·
Cutlass, thanks a million for your reply. I really appreciate it. But alas, as it stands, I could have used your advice last week when we called and checked forums and scratched our heads when I pulled his carbs and seen the plugs over the pilot jet!! I thought the last guy must have plugged the wrong ports since it makes sense that they have to be open!! We left it open, put it all back together and it ran ok, pulled em after finding out they ARE supposed to be plugged, it woke up. We probably had a few other things set wrong or something because when we got her back together, it really woke up, up to fifty. This is why I'm thinking clutches.

And I guess I will just have to dive into them, I'm not getting any response as to what I'm supposed to be looking for or what to NOT do as I am removing the primary or pulling it apart.

Check the clutches is too vague for me. I was hoping u would say, yea you need a puller for the primary, pop her apart watch out for this or that, make sure you can see such n such make sure it does this and that wipe er down good and spray some of this miracle snake oil I found on the weights and put er back in and just TRY to keep this skis on the ground!

Any body have any good info for me before we tread into the unknown?
 

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Mr. Budget Mechanic
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Okay Mint, sorry I wasn't of more help with my last post, didn't know you'd already messed with the plugs. Still, you haven't told me if you got the jetting right. Before you start messing with the clutches I'd rule out completely whether or not it's a carb issue. As I wrote earlier, from my experience these carbs seem picky about elevation and temp changes and can be tricky to get jetted right. If you've already got it jetted correctly, then that's all well and good and then you can move on and start checking/adjusting the clutches. But so far you haven't provided me the info on whether or not it is properly jetted. Maybe that info is there in your other thread, but I have not read it. Sorry to keep harping about the carbs, but you need to completely rule out other, more easier remedied causes of the problem before you move onto troubleshooting more complex ones, otherwise you run the risk of chasing your tail.

If you haven't already, get a service manual. In it you'll find a jetting chart (where you can verify whether or not you've got the right size jets for your conditions), and several sections on how to check, troubleshoot, and tune your clutches.

Free '84-'99 Phazer manual here (it says 1984-1989 manual, but that's a typo, the manual actually covers all years of the Phazer l and ll, all the way up to 1999): http://www.snowmobileforum.com/yamaha-snowmobiles/39584-1984-1989-yamaha-phazer-manual-pdf.html

As far as clutches go, it's been my experience that there's not much you can do other than clean them without special tools (even just checking the proper sheave-to-sheave distance and sheave offset requires a special tool). Changing the weights or the springs in the primary clutch requires the use of a clutch puller. Even disassembling the secondary requires the use of a spring compressor tool. This is why I recommend completely ruling out any potential carb related causes first before jumping into clutch tuning.

The obvious advice is to clean any rubber residue off the sheaves and center shaft with lacquer thinner or some other cleaner that does not leave a residue (snowmobile shops no doubt sell a product specifically for this purpose), and then blow out the dirt, grime, rubber particles, etc., from both clutch spiders with compressed air. Other obvious advice: make sure you have the proper size drive belt and that it's not wore out. The manual gives you exact specifications for proper belt size and wear limits.

Good luck Mint Classie. It sounds as if you're real close to getting it dialed in.These are punchy little sleds and a ton of fun when they're running the way they should.
 

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Discussion Starter · #9 ·
Cutlass, thanks!

Sorry about my lack of info, I did call local service center and verified we had the correct main jet size. I did not think about the pilot jet resizing but it had the recommended main jet size of 143.8 so I figured it was all good.

I appreciate the info on the clutches, that was exactly what I was looking for! I figured it can't be too different then the comet clutches, but to hear it from the pros is all I needed.

Thanks again!
 

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Mr. Budget Mechanic
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Unless you do your riding at sea level, the 143.8 size main jets that are the standard size mains Yamaha installs from the factory, you are probably running too rich. I don't know why these sleds are jetted for sea level when they come from the factory (because in my mind, most people ride these things at elevations that are much higher than that), but I'd still download the manual and check the jetting chart to be sure that you are jetted correctly. Like I said, unless you're riding at sea level, chances are you are running rich with those big 143.8 mains. That would account for the lack of high end power. And swapping the main jets is a heck of a lot easier than messing with the clutches. I've been told that you can pull the float bowls off without removing the carbs if you remove the secondary clutch first. Make it a snap to change the main jets. I tried doing it that way when I was tuning my carbs but I couldn't loosen the clutch bolt. Got a 6' cheater pipe on a 2' breaker bar, set the parking brake, and stood on the running board and still couldn't break the bolt loose before the track started moving. That puppy is stuck.

Another simple trick that I like to do when I get an old sled (or motorcycle) is to trim off a quarter inch of the insulation of the spark plug leads to provide a better contact between the wire and the cap, therefore providing a better spark. Carefully pull off the spark plug caps and take a sharp pair of scissors and score the rubber insulation down to the wire in a 360 degree circle. Pull the trimmed rubber insulation off and you now have a quarter inch of fresh wire sticking out. Firmly twist the caps back on and you're done. Quite often you'll notice a bit of a performance boost from this simple trick alone, especially if it's an older machine that hasn't been serviced in awhile.

but to hear it from the pros is all I needed
Thanks for the compliment, but I'd hardly call myself a "pro". :)

Probably a very experienced amateur is more like it. ;)
 
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