Small Engines (Lawn Mowers, etc.): 1977 Ski Doo Everest 440E, marvel mystery oil, ski doo

Question
I just obtained a mint, (well almost) condition Everest.  This sled only has 400 miles on it and has been in controlled storage for 25 years.  I cleaned it up cleaned the carb and got it running.  The only problem I'm having is that it runs great when the engine is cool.  After a couple of minutes it runs rich and bogs out.  I've rechecked the carb and every thing seems normal, even took it in to a repair shop and they said the same.  I have great compression, (150), in both cylinders.  When I experience the rich condition both cylinders are wet.  The sled starts with one pull and sounds great at first.  What else could I be missing?  I would like to take this sled on a vintage ride someday.

Answer
Hello Randy:

What is the Compression when the Engine Bogs Out. If the Engine has Set for a Long Time and the Position of the Piston was Not Moved, then it is Highly Likely that the Rings are Stuck to the Piston and are Not Expanding as the Cylinder Expands. This Causes a Slow Loss of Compression as the Cylinder Expands Away from the Piston and Rings. You can Usually Pour a Small Amount (2 to 3oz) of Marvel Mystery Oil Into the Cylinders and Allow it to Set Overnight. You May have to Repeat this Process 3 or 4 Times. If Anything will Free the Stuck Rings, the Marvel Mystery Oil will. If you Hit a Snag or this Does Not Correct the Problem,  I am Here if You Require More Assistance. Hope this Helps. Let me Know What Happens, Please. May the All Mighty Bless You and Yours. Thanks.

Good Luck

Respectfully

John

PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 8pm EST (US). My New Day Starts then. Thanks.

Respectfully

John