SPORTSMAN XP 850 - SPARK PLUG FOULING
The all-new Sportsman XP 850 has a unique engine sound at idle. As a result of this unique engine
sound, Polaris has discovered that it has become common for dealers to demonstrate the unique
sound to consumers by starting the engine and immediately applying the throttle to hear the
impressive engine.
Although this effectively demonstrates the unique sound of the 850 engine, some Polaris dealers have
fouled spark plugs as a result. Applying throttle to a cold engine causes excessive fuel to be injected
into the engine. If the engine is not allowed to reach operating temperature, carbon deposits may build
up on the spark plugs if repeated on multiple occasions.
Fouled spark plugs typically result in an engine that will not start or runs on one cylinder until the spark
plugs are either cleaned or replaced.
SERVICE RECOMMENDATION:
Fouled spark plugs can be prevented by allowing the engine to reach normal operating temperature
before turning off the ignition key or by avoiding unnecessary engine acceleration when the engine is
still cold and in the EFI enrichment mode.
The best way to prevent the issue is to ride the Sportsman XP. If that is not possible, be sure to allow
the engine to idle for a few minutes before turning off the ignition key to avoid fouling the spark plugs.
A model year running change to the 2009 Sportsman XP 850 was implemented on 1/05/09 to help
prevent spark plug fouling for consumers who frequently operate their ATV for short periods of time.
The production Champion REA6MC Spark Plug (PN 3022111) has been replaced by a Champion
REA8MCL Spark Plug (PN 3021732) with a higher heat range. NOTE: These two spark plugs are
interchangeable.
IMPORTANT: Fouled spark plugs are not considered a defect and are not covered by warranty.
_________________
- Sportsman XP 850 -

 

While your at it get rid of the champions and buy ngk in the hotter heat range.

 

<div class="FTQUOTE"><begin quote>Originally posted by: Kerbbirds

While your at it get rid of the champions and buy ngk in the hotter heat range.</end quote></div>

I wish...too bad NGK doesn't make one that will work..heck far as I can tell no one but Champion makes a plug that will work in the 850.. [img]i/expressions/face-icon-small-sad.gif[/img]

 

ductmate -- GREAT info!

This is kind of why I started a thread on the build date location of the XP. When I go in April and pull the trigger...I am definitely going to check the build date. And now with this info...will talk with the dealer about the plugs. Maybe as part of the delivery inspection...have them check the plugs?!?! [img]i/expressions/face-icon-small-wink.gif[/img]


biz
[img]i/expressions/face-icon-small-smile.gif[/img]

 

Also have them check to make sure it has the latest ECM calibration..

 

Does the spark plug and ecm flashing apply to the 850 only and not the 550. thanks

 

<div class="FTQUOTE"><begin quote>Originally posted by: HIGHOCTANE

I wish...too bad NGK doesn't make one that will work..heck far as I can tell no one but Champion makes a plug that will work in the 850.. [IMG][/IMG]</end quote></div>

Yep, and if NGK comes out with a plug, I bet most of the fouling issues would go away.

The only thing I can think of is that Champion cut a sweet deal with Polaris to come up with a plug that only Champion can supply.

Champion should focus more on making a better plug, and then they wouldn't have to use such sneaky tactics.

I think somebody said it correctly a while back... "friggin lawnmower spark plug". LOL

On another note, I'm not buying into this "let it warm up until it's at perfect operating temperature" before shutting it off or unnecessary acceleration. There are a LOT of other EFI ATVs' (and other vehicles) that don't require such babying.

Either there's an issue with the plug, or an issue with the EFI program/components, or combination of both.

I bet at some point... it will "mysteriously" go away. LOL

 

<div class="FTQUOTE"><begin quote>Originally posted by: Rutcutter

Also have them check to make sure it has the latest ECM calibration..</end quote></div>


Excellent point! Absolutely will do that...


Thanks,
biz
[img]i/expressions/face-icon-small-smile.gif[/img]

 

You know i was reading my owners manual and happened to look at the spark plug section for my 550 and they recommend NGK's. It's too bad that the 850 doesn't! [img]i/expressions/face-icon-small-sad.gif[/img]

 

I wanted to let you know that ngk does make a plug for your 850 infact they make 2 different ones, you can buy the ngk resistor plug for about 6.99 from rockymountainatv.com the part number is LZKAR7A the other is an ngk iridium plug you can actually get from your local autozone or napa, or any of them, but they are not cheap, somewhere between 15.00 and 23.00 each. i hope thai helps you out. i went through hell trying to find a plug outher than the champion plug.