[Serge7]

Bought a used Rhino ,,06,,660 Previous owner. Informed me that it needed some work.. He had head gasket changed. BUT ,Mech did not change valve seals, Hence it smoked a little bit.
Not a game changer, Also needed a new belt. Still not a problem. Realizing it was not a new unit. Oil was still milky. Last winter ,I was recuperating from surgery. This spring ,I started working on it, You might have already guessed.. The more I work, the deeper it gets.Ran like it was out of time. Thought the mech may have let chain slip while doing cam removal, Lined up all marks and ,cam was off about a tooth. Replaced head gasket again,installed new valve seals, Changed oil.. Kitted Carb. ,new belt, new air cleaner. All back together. Torqued to spec's.. Fired it off n. Idles great, did not want to rev up, Same prob as when I bought it. Checked fuel delivery, Pump working good lines full, Was checking oil, and left oil dip stick loose \screwed in half turn. It blew out and big oil mist from blowby in crankcase. Oil is still clear, Check compression is 40 lb/s. Looks like compression is all in crankcase. Does not want to back up. Kind of humps up like brakes are locked. They are not locked.. Anyone want to try their hand at this problem child??

 

[fz1dave]

That compression is way too low. Should be at least 125 or so. Ground the spark plug, pinch or disconnect the fuel line and hold the throttle wide open when cranking to get an accurate reading.

What exactly did the carb kit entail? Any intake or exhaust mods?

 

[Serge7]

Kit was a pretty standard kit. New jets and needle valve seat. Float , Idle adjuster screw with o-ring spring and washer, Had to drill cover out of idle screw, Done that before.Wth auto carbs. Nothing to heat up anything, Trying to keep it stock. To get running,.Long needle that goes in big diaphragm, with seat.Little o-rings Cleaned all passages. Idle passage was almost blocked solid, O-ring on adjuster was a glob. Hard to figure why it even started. used 2 can's of carb and choke cleaner. Had to use impact driver to get screws out of float bowl. Replaced them all. Like $15.00 @ Dealer. @ 2 Cam cover bolts were ruined by earlier mech , 6mm by 155mm bolt $14.65. 6mm by 55mm $4.00 $20.62 for both bolts.
Did above for reading Lot's of blow-by. More blow-by than a 1962 900 plus cube V8 Mack diesel., 2 Smaller cover bolts were available at ACE .99 cents piece New jug and piston w/rings due 8 July

 

[Serge7]

New kit is in this am Checked Pisto Kit, and piston is different from one in engine. Piston in engine has a dome top with fly cut for valves to clear,, One that came in kit is flat on top. Not familiar with engine. Will this new piston work?? Kit has new clinder ,New gaskets, spark plug and wrist pin.

 

[Serge7]

New kit in hand. Checked it out New piston is different from one in engine. One in engine is domed and fly cut to allow valve ctearanc .. New one is flat. Any problem with replacing domed piston with new one?? Have new jug also.

 

[Serge7]

UPDATE Installed new Piston Rings and Jug cylinder. Actually runs . 125 to 130 Compression.. Idles decent, and does answer throttle, Then quits.Still adjusting on carb. Reran valves. Helped some. Slowly getting there... Who makes a good carb for 660/2006 ? IN case I decide to get tired of fooling with iit?

 

[sandbuster]

Yamaha - everything else is a crap shoot.