Service and Tuning Notes From the October/November 2005 Issue os Snowtech

Yamaha RS Diagnostic Codes
The new three-cylinder RS 4-strokes from Yamaha are fitted with a comprehensive self-diagnostic system that will, upon detection of an electrical problem, display a code on the LCD gauge that indicates the potential source of the problem.

If you should see the warning indicator, engine icon and a two-digit number flashing (in the odometer area, alternating between current mileage and an error code) you will want to record the two digit number so your technician can determine the cause of the fault code.

For example, if there is a problem with the throttle position sensor, the panel will display the warning indicator, the engine icon, and a number 15 or 16 will flash in the odometer display every two seconds (with the current mileage being displayed the rest of the time).

Or, if the number 86 is displayed instead, you’ve just activated the cold engine protection rev limiter. This can happen if you start the sled up and take off with little or no engine warm-up.

Cleaning Tools
When detailing a sled for show or simply to clean it, many times it is handy to have a non-metal item for scraping purposes. This is when something like a Popsicle stick or a plastic blade works well. You can actually buy bags of clean Popsicle sticks at craft stores and even Wal-Mart, in the craft area (you can get someone to buy them for you so you’re not seen in that area of the store).

For example, cleaning the crap out of the aluminum corners and crevices. Not big enough for a broom, not loose enough for a vacuum or blowing out. A screwdriver would damage or scratch it. This is when a wood or plastic tool is required.

2004 Firecat Oil Line Sleeve
If you own or ride a 2004 Firecat (or Sabercat) you might want to pay close attention. There is an oil line under the engine that is known to chafe and can actually break, and we all know what happens when a 2-stroke doesn’t get any oil.

If you tip the sled up on the PTO side and remove the belly pan (12 screws) you will find the oil line and a place where there is a black piece of plastic that is supposed to protect it from chaffing and becoming damaged. Take a piece of something like a garden hose or rubber tubing a couple inches long and split it and place the length around the oil line in this area to protect it. Secure it with a couple of zip ties to keep it in place. When you find this you’ll understand, and your engine and pocket book will thank you. Thanks to “Randy in Ontario” for this tip!

Summit 1000 Intake Deflectors
A good number of Summit 1000 (and some Mach Z 1000s) that we spotted in the field last season had removed the plastic deflector that shields the intake filter material on the left side of the machine. Most riders commented on how this area would allow snow to build-up (when riding is certain types of snow) and restrict the intake surface area, some just stated the sled ran more consistently with it removed. The nylon fabric seems to be a waterproof pre-filter, capable of allowing air to flow through it but not water or snow.

Broken Airbox Fittings
Owners of Polaris models fitted with plastic airbox fittings (that the carb vent lines are attached to) want to verify these fittings are not broken. If they are broken or cracked, the carb vent lines and float bowls will not “see” the proper airbox pressure, resulting in a rich fuel delivery due to the increased float bowl pressure. The machine may not always reach peak operating RPM, fuel consumption will be higher, and overall performance will be sluggish due to the inconsistent float bowl pressure and resulting fuel delivery.

Damage to the plastic fittings normally occurs when the vent lines are removed for carb service or jetting purposes. If you are lifting or twisting excessively when removing the vent lines from the airbox, the cheap plastic fittings can break rather easily. Ideally, you want to pull the vent line straight out and away from the airbox and twist only slightly to remove the tubing from the fitting.

The best solution is to install metal fittings, replacing the less expensive plastic pieces. Thunder Products (320-597-2700) offers a complete kit of metal fittings, but takes it to the next level. The kit not only replaces the fittings with billet aluminum and brass ones, but adds “balance” lines so each carb’s float bowl sees exactly the same pressure from the airbox. This will provide a very consistent fuel delivery, sort of a float bowl synchronization if you will.

Polaris Airbox Fitting kits for carbed twins go for $19.95; kits for carbed triples go for $29.95, and are available from many performance shops like Thunder Products, Fett Brothers Performance, or Hi-Performance Engineering.

Plastic Stress Marks
When plastic has been asked to stretch or bend in a direction it doesn’t want to there will often remain white “stress” marks. For example, on a belly pan.

Many times, these white marks can be greatly minimized and almost eliminated by carefully warming the area with something like a hair dryer or heat gun. You must do so with extreme caution and slowly so you don’t warm the area too quickly. This really works well on blue Yamaha belly pans.

Handlebar Bolts Torque Specs
Quick answer this; do you know right off hand what the torque spec is for your handlebars? Normally it’s going to be quite low, something like 10-20 ft-lb (120-240 in-lb). Point is, you should be aware of the exact spec when adjusting handlebar positioning.

Another thing to be checking is the security of these bolts; some sleds are fitted with “soft” aluminum blocks, and you’ll notice more movement and loosening of the bolts on these sleds (our Firecats seem to experience this more than our other sleds).

Polaris 2005 Liberty 900 Injectors
The fuel injectors used on the 2005 Polaris Liberty twin 900s are color coded, much like Arctic Cat’s injectors were coded with a symbol (diamond, square, triangle). This is for the purpose of matching the injector flow rates to the machine electronics. And the coding should be followed when replacing an injector. Only replace injectors with one of the same color code! Mismatching of injectors can lead to improper fuel delivery and potentially engine damage.

The tips of these injectors are also very delicate, and should be visually inspected before installation. Injectors with any visual deformation or damage should not be installed, as this can cause a lean condition on the cylinder which it is installed.

Summit 1000 Update
All 2005 Ski-Doo Summit Highmark 1000 SDIs should have the pulse fitting on the crankcase replaced (by your Ski-Doo dealer) to eliminate fuel starvation and bogging. In addition to the pulse fitting, the ECM will be reprogrammed, the fuel pump will be cleaned and the throttle position sensor (TPS) will be verified and reset. A new set of NGK BR8ECS spark plugs will also be installed as part of the update through authorized Ski-Doo dealers.

Many Summit 1000s had this service performed in February or March; if yours did not, it should have it done as Ski-Doo wants all units upgraded.

Yamaha RX Oil Consumption
What is considered “normal” oil consumption for a 1000cc Yamaha RX 4-stroke engine? Anything up to one quart per 1,000 miles, according to Yamaha. With a high-revving high performance engine like this it will use some oil under normal operating conditions. Anything over one quart per 1,000 miles is considered excessive.

Many conditions can contribute to excessive oil consumption, including improper break-in, engine modifications, clutch modifications, and extended high-speed or high engine RPM operation.

Incorrect oil level checking technique can cause a “false” low oil level reading, leading the owner to believe the sled is using oil. This can also cause overfilling. Yamaha suggests checking the oil level only when the engine is fully warmed up, having run for at least ten minutes. Do not add oil unless the oil level reaches the “E” mark on the dipstick (which should be marked “L” for “low” instead of “E”, which usually means “empty”). Do not fill the oil tank above the “F” mark on the dipstick, as overfilling can cause excessive crankcase pressure and actually increase oil usage!

If excessive oil consumption is truly identified, Yamaha suggests first using their “Ring Free” fuel additive to “shock-treat” the engine and remove internal engine deposits. Two ounces of Ring Free should be used per gallon of fuel for 2-3 full tanks (20-30 gallons). After this treatment, the engine oil and filter must be changed, using Yamaha 4-S 0W-30 synthetic blend oil (or Yamaha 4-CW 5W-20). After this, Ring Free should continue to be used at a rate of one ounce per ten gallons to prevent further engine deposits.

Do It Now!
Our friends at Black Magic Racing reminded us to remind you to go out and start up your sled, like right now. Seriously. Where is your sled and how did you put it away at the end of the season? Did you take the gas out of the carbs? Did you fog it? Have you started it once a month like you should?

If not, it would be worth the effort to take 10 minutes and do this. We are not kidding. The gas that you left in it from your last ride is most likely shot. After as little as 2 weeks in the vented tank, the "light ends" of the fuel (the good stuff) floats away and the gas is losing its octane big time. The carb jets, especially the pilots, are turning green and slowly plugging up. The main jets are leaning themselves out and by fall, a 470 main jet could be reduced to something silly like a 270. You know what that means; lean seizure. If it starts at all, that is, as plugged pilot jets will pretty much keep the sled from idling.

Here at SnowTech we’ve found dropping a Fitch Fuel Catalyst into the fuel and running this treated fuel into the carbs to be the most effective way to keep the fuel fresh and the carb jets from turning green. You can do this with a gas can, or use the sled’s fuel tank itself, as these devices constantly “crack” the heavier fuel molecules into lighter ones, helping to maintain fuel volatility in storage environments.

Black Magic suggests adding a small amount of fresh fuel once a month and starting the engine to keep the seals lubricated and from drying out, as well as to keep fresh fuel in the float bowls. Bring it up to operating temperature to burn out all of the moisture, but don’t run so long that you overheat it. You will be glad you did and sad if you didn't!

Spare Belt Locations
With real estate becoming a precious commodity under the hoods of many new sleds, finding a place to carry a spare drive belt is becoming challenging. Nobody in their right mind would leave home without a spare drive belt!

A couple of things to remember when mounting a spare drive belt, whether it is in a factory-located belt clip or you’re using cable ties to keep it in place, or trying to cram it into any nook or cranny you can find; make sure the spare belt doesn’t contact things like a coolant hose. It will sit there and vibrate and move around, and over time this sort of contact can wear through things like rubber coolant hoses and plastic wire insulation. Contact with the exhaust system is not wise, as this will deform the belt edges and render it useless.

It used to be accepted practice to coil up a spare belt and throw it into the trunk, but this is now discouraged unless sit is your only option. The belt manufacturers tell us this is hard on the new compound belts and shouldn’t be done any more.

We still try to place the spare belts on top of the clutch cover, when possible, and really like how Arctic Cat hides them under their removable seats on so many models. As long as you remember it is down there! Spare spark plugs, however, don’t fare as well down under the seat….

Gas Tank Neck Extension
We have just received a note from Arctic Cat regarding the 2006 M7 models within a VIN range of 4UF06SNW96T111797 - 4UF06SNW06T112997 and the 2006 Crossfire models within the VIN range of 4UF06SNW46T113280 - 4UF06SNW26T115934.

According to Arctic Cat, "Due to the unforeseen circumstances, Gas Tank Neck Extension (p/n 1670-801) was not available during the production of the above models; consequently, some of the affected snowmobiles were shipped without the extension installed."

Of the two Crossfire models we had last season, one had this installed and one did not. It appears the white plastic “sleeve” keeps you from filling the gas tank to the top, the purpose being to keep fuel from dribbling out of the vented gas cap. It also reduces the amount of fuel that can be added to the fuel tank.

If your sled falls within these VIN numbers, your Dealer should contact you to install this piece.