Another thing to consider is the 850 Polaris does Not require more oil added to the gas tank. Some dealerships like mine are Still adding extra oil to the 1st tank and it is fouling plugs. Mine was so full of oil I hand to drain the pipe when I got home and change the plugs. If your friend was trying to heat soak the motor on a stand that is not required or recommend on this motor. There was a tag on the gas tank when he bought it stating no oil is needed in the tank. My dealer was also adding 87 octane from their tank out back (who knows how old that is). I drained my tank and installed fresh 91 non ethanol. Mine is running very strong now with no bog. Also if his DET light is flashing then it would automatically close the exhaust valves to reduce engine rpm, restarting the engine resets this (page 38 of his owners manual). On page 64 and 65 it tells you that the engine management system will automatically reduce engine power and create a misfire condition if the motor is overheated.
Here is a note from Polaris on break in:
7/16/2019
New Snowmobile Break-In
Engine Break-In
The first tank of fuel is considered the break-in period for the engine of your Polaris® snowmobile. Careful treatment of a new engine will result in more efficient performance and longer life for the engine.
Excessive heat buildup during the first 3 hours of operation will damage close-fitted engine parts. Do not operate at full throttle or at high speeds for extended periods during the first 3 hours of use. Vary the throttle openings and vehicle speeds to reduce friction on all close-fitting machined parts, allowing them to break in slowly without damage.
On fuel-injected models, the engine management system utilizes both a fuel injector break-in period and oil pump enrichment program. The duration of these break-in programs is independent of each other and is timed out based on engine run time. Regardless of these automatic engine break-in and enrichment features, engine break-in procedures must be performed when the engine is new or overhauled.
Oil and fuel recommendations during the break-in period vary depending on the specific model of your POLARIS snowmobile. Some models require premix of the first tank of fuel. Oil added to the fuel and oil injection systems will provide necessary break-in lubrication. Be sure to consult your Owner’s Manual to find the instructions for your particular vehicle. You can access your Owner’s Manual online by
clicking here.
Never mix brands of oil. Serious chemical reactions can cause injection system blockage, resulting in serious engine damage. Oils also may be incompatible and the result could be sludge formation, filter blockage and reduced cold weather flow rates. All POLARIS oils are compatible with each other.
Drive with extra caution during the break-in period. Perform regular checks on fluid levels, lines and all other important areas of the snowmobile.
Drive Belt Break-In
The break-in period for a new drive belt is 30 miles (48 km). During this time, vary the throttle position under 50 percent and limit full throttle use.
New drive belts should be washed with warm, soapy water and allowed to air dry prior to use.
Always take time to warm up the belt and driveline prior to operating the snowmobile. Free the track and skis from the ground before engaging throttle.
Quickdrive® Belt Break-In
The break-in period for a QUICKDRIVE belt is 100 miles (160 km). During the 100 miles of belt break-in, the rider will hear a sound made by the drive system. After the break-in period, the sound will become similar to that of a traditional chaincase.
Improper track tension can result in track ratcheting, which will affect QUICKDRIVE belt durability. Always maintain proper track tension.
During the break-in period, this belt sheds a fiber-type material in and around the drive system. Use a dry shop towel to clean the residue.
Stop occasionally and allow the snowmobile to cool after high throttle or high track load events. This will help the QUICKDRIVE belt achieve maximum performance. It also will break in the engine, drive belt and sprockets properly.
On-trail break-in should be performed at speeds no more than 50 mph (80 km/h).
Ensure a longer life for your engine, belt and other key components
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