Polaris introduced the plastic chaincase covers a while back on their sleds that have been giving some people a lot of headaches.
Polaris will not update the cover to the new magnesium or add insulation under warranty, from my experiences.
Some things you are left to improve on your own if you want to have trouble free miles on your sled...
That being said, there are many out there with plenty of leak free stock chaincase miles out there.
With some attention to this area and some precautions, you can minimize the possibility of leaking, easily, for little $.
There are 3 causes of most of the leaking of chaincases not including putting a hole in the case if you break a gear or chain or run the chain too loose.
First: Most of the leaking comes from being lifted by a forklift... Unless the person operating the lift really knows what they are doing, the cases will spring a leak... if they lift it in the wrong place and leakey-leakey
The second big cause is the exhausts proximity to the chaincase cover... depending on the exhaust and how close it is to the cover, it will cause problems.
The Second cause is the fact that there is a large distance between the bottom chaincase cover screws and the case can bow out and leak... This bowing was fixed with the addition of the lower chaincase support bracket that was installed standard on the 2008 (warranty on the 2005 and 2006 otherwise $23 out of warranty). ]There are many ridges and dimples on this piece to apply pressure in the right places... don’t just cut one out of plate or sheet metal and expect it to work correctly.
If your cover is already leaking, buy another cover and gasket UNLESS it is under warranty then have your dealer replace it and add the bracket if needed.
A forklift can raise havoc with an aluminum chaincase cover as well.
Get a sheet of DEI thermal insulation (24 x 21") from Summit Racing $34 and you will have enough for two chaincases (hook up your buddy). OR get the 48 x 21" piece for $62 and have enough to do all of your under hood insulation and ditch the water holding foam (especially in the nose of the sled near the pipe).
To get to the chaincase, you will need to remove the muffler side panel and the muffler... If you don’t already have one, buy a good spring removal tool from your dealer or any of the parts houses like www.denniskirk.com or http://www.hiperf.com/ATV/acatalog/Shop_Equipment___Tools.html. The spring tool will come in handy for a lot of different operations on your sled. There are also many people out there that have made their own.
WEAR SAFTEY GLASSES/GOGGLES when working with exhaust springs... they can fly of and hit you in the eye, causing serious injury or loss of your eye!!
The third cause is the exhausts proximity to the chaincase cover and the heat it throws off... depending on the exhaust and how close it is to the cover, it will cause problems. Venting this area can help keep the temps down greatly as well.
To fix the heat problem, start with an un-warped, non leaking cover installed on the sled...
get a sheet of DEI thermal insulation (24 x 21") from Summit Racing $34 and you will have enough for two chaincases (hook up your buddy). OR get the 48 x 21" piece for $62 and have enough to do all of your under hood insulation and ditch the water holding foam (especially in the nose of the sled near the pipe).
Make a paper template of the chaincase cover about 1/2" larger than the outline of the cover, cut it out and trace it onto the insulation, paying attention to the layout so that once cut, the foil will be on the outside of the case once installed. On the 2006 -2009 covers cut the insulation out with heavy duty scissors. Clean the cover very well with degreaser or Denatured alcohol and allow it to dry. Peel the backing from the insulation and carefully install it onto the chaincase cover... Re-install
Link to the 24" x 21" Insulation
http://store.summitracing.com/partdetail.asp?autofilter=1&part=DEI%2D050501
Link to the 48" x 21" insulation
http://store.summitracing.com/partdetail.asp?autofilter=1&part=DEI%2D050502
DEI insulation material
Insulated cover on a 2005 RMK
Pic of lower bracket #24
Polaris will not update the cover to the new magnesium or add insulation under warranty, from my experiences.
Some things you are left to improve on your own if you want to have trouble free miles on your sled...
That being said, there are many out there with plenty of leak free stock chaincase miles out there.
With some attention to this area and some precautions, you can minimize the possibility of leaking, easily, for little $.
There are 3 causes of most of the leaking of chaincases not including putting a hole in the case if you break a gear or chain or run the chain too loose.
First: Most of the leaking comes from being lifted by a forklift... Unless the person operating the lift really knows what they are doing, the cases will spring a leak... if they lift it in the wrong place and leakey-leakey
The second big cause is the exhausts proximity to the chaincase cover... depending on the exhaust and how close it is to the cover, it will cause problems.
The Second cause is the fact that there is a large distance between the bottom chaincase cover screws and the case can bow out and leak... This bowing was fixed with the addition of the lower chaincase support bracket that was installed standard on the 2008 (warranty on the 2005 and 2006 otherwise $23 out of warranty). ]There are many ridges and dimples on this piece to apply pressure in the right places... don’t just cut one out of plate or sheet metal and expect it to work correctly.
If your cover is already leaking, buy another cover and gasket UNLESS it is under warranty then have your dealer replace it and add the bracket if needed.
A forklift can raise havoc with an aluminum chaincase cover as well.
Get a sheet of DEI thermal insulation (24 x 21") from Summit Racing $34 and you will have enough for two chaincases (hook up your buddy). OR get the 48 x 21" piece for $62 and have enough to do all of your under hood insulation and ditch the water holding foam (especially in the nose of the sled near the pipe).
To get to the chaincase, you will need to remove the muffler side panel and the muffler... If you don’t already have one, buy a good spring removal tool from your dealer or any of the parts houses like www.denniskirk.com or http://www.hiperf.com/ATV/acatalog/Shop_Equipment___Tools.html. The spring tool will come in handy for a lot of different operations on your sled. There are also many people out there that have made their own.
WEAR SAFTEY GLASSES/GOGGLES when working with exhaust springs... they can fly of and hit you in the eye, causing serious injury or loss of your eye!!
The third cause is the exhausts proximity to the chaincase cover and the heat it throws off... depending on the exhaust and how close it is to the cover, it will cause problems. Venting this area can help keep the temps down greatly as well.
To fix the heat problem, start with an un-warped, non leaking cover installed on the sled...
get a sheet of DEI thermal insulation (24 x 21") from Summit Racing $34 and you will have enough for two chaincases (hook up your buddy). OR get the 48 x 21" piece for $62 and have enough to do all of your under hood insulation and ditch the water holding foam (especially in the nose of the sled near the pipe).
Make a paper template of the chaincase cover about 1/2" larger than the outline of the cover, cut it out and trace it onto the insulation, paying attention to the layout so that once cut, the foil will be on the outside of the case once installed. On the 2006 -2009 covers cut the insulation out with heavy duty scissors. Clean the cover very well with degreaser or Denatured alcohol and allow it to dry. Peel the backing from the insulation and carefully install it onto the chaincase cover... Re-install
Link to the 24" x 21" Insulation
http://store.summitracing.com/partdetail.asp?autofilter=1&part=DEI%2D050501
Link to the 48" x 21" insulation
http://store.summitracing.com/partdetail.asp?autofilter=1&part=DEI%2D050502
DEI insulation material
Insulated cover on a 2005 RMK
Pic of lower bracket #24
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