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Grizzly Recall

14905 Views 0 Replies 1 Participant Last post by  madmudder


Dear Grizzly Owner:
Thank you for purchasing a 2002 or 2003 Grizzly 660. We are confident that this top-of-the-line model gives you
performance, comfort, and convenience unmatched by any other ATV on the market.
Some owners of Grizzly 660 ATVs like yours, however, have reported a noticeable loss of engine performance or
an engine misfire when riding due to heat-related problems. This problem has also been noticed by riders operating
in high ambient temperature with certain kinds of fuel (such as “winter” fuel or reformulated gasoline, also
called “RFG”) and at a higher elevation. Idling or operating the unit at very slow speeds for an extended period
will also create heat-related problems due to insufficient air flow and excessive heat retained in the engine compartment.
Shutting off the engine momentarily and restarting the engine under these conditions will cause hard
starting and temporary engine misfire or sputtering as well. If you have experienced this heat-related performance
loss with your Grizzly 660, this letter has important product information regarding the performance and potential
safety of your Grizzly.
In the conditions described above, even a properly maintained Grizzly 660 could experience engine performance
loss. This is because temperatures in the engine compartment can rise in these particular conditions to the point
that gasoline in the fuel system vaporizes. This fuel vapor can lead to the loss of engine performance or misfire,
which can create a hazard to a rider who is going up an incline.
Yamaha has designed a Heat Kit for the Grizzly 660 ATV to insulate the fuel supply and provide additional ventilation
for the engine compartment. The kit includes a Fuel Tank Insulator, a Fuel Hose Insulator, Exhaust Cover,
and two new Side Covers which are vented to allow more cooling air into the engine compartment area.
To prevent the loss of engine performance or misfiring related to operating the Grizzly in the above-described conditions,
please make an appointment with your Yamaha ATV dealer to have the Heat Kit installed on your Grizzly
660 at no cost to you. Installation of the Heat Kit takes approximately 30 minutes, although your dealer may need
to keep your ATV longer depending upon his service schedule. Please take this letter with you when you take your
Grizzly 660 in for the installation.
Proper maintenance is essential for best engine performance. A poorly maintained engine is more likely to be
adversely affected by high temperatures in the engine compartment area. Therefore your dealer may advise you
that your ATV needs a tune up or regular maintenance (including proper valve adjustment, a properly serviced air
filter, and the right carburetor jetting for your normal riding conditions). Any necessary maintenance will not be covered
under this Heat Kit installation program, but it is highly recommended to prevent future engine performance
problems or misfires. Also be sure the radiator is kept free of anything, such as mud or leaves, that would reduce
its effectiveness and cause the engine to run hotter.
We thank you again for purchasing a Grizzly 660. We hope that this information will help you enjoy the performance
from your Yamaha that it was designed to give for many years to come.
Service Division
Customer Support Group
January 26, 2004
6555 Katella Avenue, Cypress, California 90630-5101 (714) 761-7300
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