Snowmobile Repair: Yamaha VK540-11 1996 snowmobile, yamaha vk540, denniskirk

Question
The left cylinder misses and runs rich on low RPM but seems to be okay on high RPM.  I inverted the ignition on the cylinders and the left still has the problem.  Spark plugs are okay.  There is no leakage of the cranks seals.  The compression in both cylinders is 110 and 110. The Reid valves are okay. When I lean the (single) carburator the left cylinder seems to run okay but the right becomes too lean.  When I set the right cylinder to good running mixture the left starts to act up and misses again.  I can't find the problem with this one, do you think that you might be able to help me figure it out? ( only 1800 miles on the machine)

Thanks very much for your help.     Len

Answer
Hello Len,
 
Sorry I wasn't able to get back to you sooner. Sounds to me like two things could be holding the sled up. I would recommend having the coil tested, or better yet, replacing it. You can get a new coil for about 30 dollars. http://www.denniskirk.com/jsp/product_catalog/MMYSkuDisplay.jsp;jsessionid=LYTKS...  .  Last of all, I would install a new main jet as well as a carb kit. This should fix the problem with the two cylinders getting different mixtures. Also, if the problem persists, spray carb cleaner all over the boot/flange that connects the carb to the engine/intake manifold. If, while the engine is running the spray makes a difference, install a new flange. Hope this helps. Sometimes just disassembling the carb and soaking all of the metal parts including the carb, will fix this problem. Good luck with the sled! --Arcticatman