Hard to do. You need to make sure the exchangers under the tunnel are getting warm. That way you'll know the system is working properly.
1992 Ski Doo Mach 1 (SC-10/2 suspended) March '07 SF.com Sled of the Month! (Lost in fire 4-7-13)
1992 Ski Doo Mach 1 original 2006 Ski Doo MXZ 500SS
1999 Ski Doo MXZ600 Webmaster Evergreen Valley Snowmobile Club SledNH.com Moderator