The snow is here!

Well, the snow is here.... it came early this year and to be perfectly honest.... I wasn't ready for it.  
Having said that, of course, instead of working on winter things in the summer....so they're ready, here we are, working on snowmobiles that should be being used.     Work on sleds in the summer and bikes in the winter is easier said, then done!

So, here's my son's new to him GREASY TRIPLE.  It's a 1996 Arctic Cat ZRT600

He picked it up in the summer for a great price... it was running...kind of, mostly on 2 cylinders, and you could only start it by pouring some gas down a cylinder....

The first thing we did was pull off the 3 carbs.  This was harder then you'd think.  2 of the carbs had the choke plungers seized in them.  Wow. 

We finally got them freed up and went through all 3 carbs, they were actually in pretty good shape.  The setup for this sled is fairly basic, in terms of adjustments.  The only 3 adjustable items for each carb are the idle, the air screw and the clip location on the needle.  

We ensured everything was setup stock as per the shop manual.  The choke was setup, the plunger lift synchronisation done.  This sled would fire up and idle ok.... but would really only run occasionally on all 3 cylinders.  The two outside cylinders had weak yellow spark... they happened to run off the same coil.  So a quick trip to Royal Distributing got us a new one.  The results were immediate; bright blue spark.  

Now the sled would idle on all 3 cylinders....man it sounds snappy.  But it sounded kinda weird, and wouldn't move so good under it's own power.

We went though the carbs again, no change there.... we then noticed that the MAG exhaust pipe wasn't sitting flush on the exhaust manifold....

fixed that and it was much better... you could hear the difference.  The sled would take off, and rip..... kinda/sorta/sometimes.... it would pop and backfire... here's what we found...

While the sled was idling, I would remove one sparkplug boot at a time to see if anything changed..... MAG, engine sputtered, gave me a good shock, PTO, engine sputtered, gave me a good shock, MID no shock..... but i could see arcing from the middle of the sparkplug wire to a hose clamp on the coolant pipe.  You could see that at some point, the wire rubbed through, so it clearly was grounding some of the time... taped that up and woah.... it's fast. 

If Zach says it's fast...... it's fast.  He was hard pulling the length of the field ..... skiis off the ground and just screaming.  We still have some tinkering to do as there is a low end bog, and it needs a new brake reservoir assembly... but she's gonna be a ripper!