I found this great post over on Snowest, and thought it would fit great over in the How-to. Just stealer information from Ron over in the Polaris forum.
Polaris P85 Drive Clutch
Care of your drive clutch will extend its life by years. A worn or out of balance clutch is hard on the crank, the drive belt & will reduce performance.
Under Hood Ventilation-At a minimum-install shock tower vents & create flow through ventilation-add vents or increase existing openings at the rear of the cowling. Venting will reduce clutch temps by 10-15 degrees-but not enough to offset poor clutching. New sleds are loaded with foam and they have inadequate ventilation because of EPA noise emission requirements. Foam also draws moisture so remove it. The remaining residue can be removed with 3M tar & bug cleaner. While venting reduces belt heat it is only part of the solution.
Clutch Health-If your clutches run cool they last longer. You should be able to hold your hand on the surface after some long pulls. Hot clutches cause excessive belt wear, clutch wear and are indicative of another problem. I.e. clutch is not dialed, alignment off, broken motor mount, etc. Oak Harbor sells a digital laser temp tool for $30 that is accurate within + or – 2 degrees.
Servicing the Drive Clutch on the Sled-Remove the belt and use two long flat blade screwdrivers to open the clutch. Gently pry with the tip under the spider using the second one once the first screwdriver loses leverage. Place an object (deep well socket) behind the spider to hold the clutch open. Now the rollers and weights are free. You can change weights or clean the bushings. I use a magnet to hold the weight as I remove the bolt.
Clean the wt & roller bushing by spraying LPS-1 into the bushing while rotating the roller. Do not use an oil based product or WD40 since they will attract belt dust. For the wts I put an allen wrench in the bolt and spin the bolt as I lube the bushing. Use a paper towel and air gun to remove excess lube. You can detect a worn roller as you clean-it will have vertical slop. Polaris rollers seem to last forever, but they can go bad. Changing rollers requires special tools to remove the spider. During the season use an air gun to remove debris from the clutch often.
Check the weights for side play since they will eventually wear a “V” at the base of the clutch tower over time. This “V” will eventually result in the tip of the weight swinging off the roller and contacting the spider. When this happens the clutch hangs and the clutch shifts erratically. Flat rollers or flat spots in weights can occur. This condition also creates more wear on the sides of the weight bushing. If your weights run true you will wear the clutch bolt before wearing out the weight bushing.
Clean the clutch sheaves often. Steel wool, fine sandpaper, hot soapy water, Alcohol, cloth with comet cleanser & hot water-take your pick. Brake cleaner & Carb cleaner work but leave belt residue in the pores of the aluminum.
Placing the clutch in the dishwasher can create domestic issues.
Replacement Weight bushings by Comet are available. (Western Power Spts. #208342-3 are $21.95) To remove a weight bushing you need a tool with a shoulder.
You can also buy steel Comet washers to shim the weight and keep it true in the clutch. (WPS part #204203 6@$4.50) At 500-1000 miles there is enough wear that a single washer will usually fit on the thrust side of the weight. The clutch turns counterclockwise so looking down at the weight nearest you; it would be the right side of the weight is the thrust side. You may need to grind a little off at the base to square the surface for the washer-a Dremmel works great. The slot for the weights will be wider at the top and narrow at the bottom (V) so grind the bottom to square the opening. If you are ambitious you can add the washer to both sides & then all wear is to a washer that can be replaced. This small amount of material won’t change clutch balance much. Once you are done with clutching it’s a good idea to have your primary balanced again.
TIP-The Polaris bolt has a straight shoulder at the end of the thread that will hang up on the washer or weight bushing during insertion. Gently grind a taper on this edge using a bench grinder.
Clutch Removal-A good clutch puller is available from many sources including Polaris. Remove the clutch bolt and insert the puller-tighten till the clutch comes off. There are various methods of holding the clutch while you tighten the bolt; I like a strap wrench or holding tool. A 2X4 braced against the chassis and the clutch also works on some sleds. I don’t care for removing a spark plug and putting rope in to lock the piston nor do I like placing a bar through the clutch. Avoid anything that may stress your crank. Most dealers use an impact wrench-if you do then hold the clutch with one hand. Use an Impact gun as last resort & never hit the end of the puller with a hammer….Ever wonder why some cranks last longer than others?
TIP-A stubborn clutch will usually come free with application of heat to the inner sheave. Try a spot of grease on the tip of the puller and Teflon on the threads for more leverage. Put your heat gun on high and turn the clutch to apply heat evenly. Apply more pressure on the puller and apply more heat. Before replacing the clutch clean all grease and rust spots from the inner taper & crank stub. 200-600 grit emery paper can be used to polish the surfaces. Replace the clutch after cleaning the stub & inner bore-see Indy Dan's post # 20 below.
TORQUE SETTINGS: Drive Clutch
800 Clean Fire torque 80#
700 Clean Fire-80# (07 & newer)
900 & 700 (866&755) Liberty Engines torque 96# (05 & 06)
Other Liberty Engines torque 50#
Older Fuji Engines torque 45#
Torque the 900 at least once more after a short run or elevate the sled & run the track, grab the brake, repeat several times & torque again.
IMPORTANT*** When replacing the outer drive clutch cover make sure to align the X on the spider with the X on the cover.
Your clutch is balanced so why not balance the weights? Polaris allows a tolerance of + or – 1 gram. I always weigh and balance all clutch weights. When you are satisfied with clutching setup, it’s a good idea to have a machine shop rebalance your clutch with the weights installed.
Clutch Alignment-Just some brief things to consider. New sleds should come in spec & is included in normal dealer setup. At least annually check offset and I always check the center distance on a new sled or after an “event”. Center wrist pin but you can cut them with scissors too.
To remove the spider you need 3 tools (a,b &c below) & I keep my heat gun handy. To remove the spider lock nut I’ve found it helps to have a friend stand on the spider nut tool so it doesn’t pop off (strips the openings) & I use a 4’ length of pipe for leverage. Torque is 120 lbs on reassembly.
Some handy clutch tools are:
a. Clutch Holding Fixture
b. Spider Nut Tool
c. Spider Tool
d. Spider button removal tool
e. Team Driven tool to change springs
f. Clutch holding tool & clutch puller
g. Clutch Offset tool
Starting Line Products & Polaris have a good selection of tools that many dealers carry or can order. Go to www.startinglineproducts.com
and check special tools for pricing & selection. I like SLP tools for price & performance.
Team Driven Clutch-Just a note since these require very little care. I clean mine during fall service and adjust deflection as the belt wears. It’s a good idea to remove the clutch during the year to clean & lube the jackshaft and driven clutch (inner shaft opening). Clean, remove any rust and then add a light coat of lithium grease. Wipe most grease off or it will end up on the belt or clutch. Watch that the washers don’t follow the clutch off the shaft. The older Team clutches had a problem with springs binding until they reverse wound the springs. Starting Line sells Delrin washers (set of 3) to free movement. I still put one on each end of the spring just for insurance.
SLP also sells a 1/16” shim washer that you can use to fine tune the shift on a Team Helix. Fits under the snap ring so It reduces the length of the aggressive portion of the shift angle.
Older Polaris Driven-These require more service and performance drops when they aren’t in top condition. To service put the clutch on the floor & press the helix down with a knee to remove the snap ring. A tool is available from SLP. You may have to turn the helix slightly clockwise. Carefully remove your knee since the spring may send the helix flying. Note the location of the spring in the helix for reassembly. Some helixes have a number 1 to 4 to identify the sequence of holes. Normally the spring is in hole 2 or 3. Some A/M helixes have 5 holes. Also note the location of shim washers behind the snap ring and inside of the clutch. Clean the clutch with hot soapy water & replace the 3 buttons frequently. Polish the helix towers with emery paper for a smoother surface. Add a very light coating of lithium grease to the shaft or carefully spray liquid graphite on the shaft. Never lube the helix. Reassembly requires installing the keyway, spring, & twisting the helix 1/6 turn clockwise-then pressing down to add the shim washer & snap ring.
Adjusting Belt Deflection- (See chart ) Suspend the rear of the sled and run the track to allow the driven to shift out. Measure the deflection (distance from thesag in the belt to the bottom of the straight edge). Less deflection equals a “lower gear” ratio at initial start. I try to maintain ¾” or less (spec is 3/4” to 1 1/4”). If you get deflection too tight you will see resistance in the primary, hear a squeal, or the sled will creep forward. After you have “broken in” your belt belt set deflection. Check your belt frequently for signs of excess wear or cords coming out of the sides. Don’t wait for a belt to grenade before changing it, a blown belt is a known issue with premature crank failure. Screw in the L shaped belt removal tool to take pressure off the allen bolt while making the deflection adjustment.
If your belt has been hot & slipping it can build a “glaze” that makes the surface slick. Remove the glaze gently with sandpaper or by buffing with a wire wheel. Try not to remove material only rough up the surface.