Well last weekend the wife and I were cruising around the lake and the sled started to sputter. Limped it back to the bar and it just died. Thought maybe i fouled a plug. Nope all 3 dry. put it on the trailer and went home tore into it last night and the center cylinder went down. not sure why. 
idle screws at 2, needles at 3.25. Not much changed all year. The center piston rattles when it is turned over too. Its pretty much gone. Here are the pics. Any ideas what happened??? The center head is real black. the other two look ok. It has some pitting in it that looks old too. I say that because the "black" on the head looks to be covering it up...?? The coolant jug was FULL when we left for the trip. When we tore it down, the head was only about half full so it lost some somewhere. Weather it lost it from a leak, or in the motor (gasket), has not been resolved yet.
idle screws at 2, needles at 3.25. Not much changed all year. The center piston rattles when it is turned over too. Its pretty much gone. Here are the pics. Any ideas what happened??? The center head is real black. the other two look ok. It has some pitting in it that looks old too. I say that because the "black" on the head looks to be covering it up...?? The coolant jug was FULL when we left for the trip. When we tore it down, the head was only about half full so it lost some somewhere. Weather it lost it from a leak, or in the motor (gasket), has not been resolved yet.
Temp light never came on.
yamyrider
Active member
the plug looks like my center plud did. My head is perfect but cylinder and piston are done. The piston is really bad and scored on both sides. I had a hard time removing the jug the piston was so scored. Left marks on the cylinder. I had no coolant in the reservoir. I had just put a new opticool gasket and rear cooler. I had just installed a new piston in center and this was my first ride last night. I know how you feel. Let me know what you find
Readjust ur oil pump sound like it leaned out or u put ur plugs in too tight ! Re adjust the oil pump ! Do the air boot look good ! Ur burning hot somewhere ! Get new pistion and jugs carb kit ! Oil pump kit ! New air boots wouldn't hurt ! Have ur carbs set by a pro if ur don't have all the knowledge and sync tool! I guess my overall answer by the red brown along with that deep yellow on the pistion ! Might cost ya a pretty penny but get a certified machanic ! And order ur own parts ! My guy is pretty good 48 bucks an hour for labor and they got all the machines for boring porting ect! Did I mention a sled head too!
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they are all lean(pistons) but do to excessive heat they would be.......so the question is where did all the coolant go? They will spit some out when they run hot on the right side by your foot, but you usually noticd this on the running board or your right boot!.... but if it was halfway down when you took off the head without draining it, its got a leak somewhere, either the waterpump weep hole? heat exchanger? or hose leaking somewhere?
add: flip engine over and look at w/p weep hole in bottom of case
add: flip engine over and look at w/p weep hole in bottom of case
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turbotod
New member
Check this
A few years ago my center cyl. went on me, upon further inspection I found that a pressed in fitting on the bottom of the crank case under the center cyl. had fallen out. So I traced the hose back and found it went to the oil pump. Man was I pissed.Just my luck when this happened not only did it starve the center cyl. of oil but also alowed air to get in thus it spit. The next engine I instaled I JB welded all three fittings on the bottom so it wouldnt happen again. Hope this helps and good luck.
A few years ago my center cyl. went on me, upon further inspection I found that a pressed in fitting on the bottom of the crank case under the center cyl. had fallen out. So I traced the hose back and found it went to the oil pump. Man was I pissed.Just my luck when this happened not only did it starve the center cyl. of oil but also alowed air to get in thus it spit. The next engine I instaled I JB welded all three fittings on the bottom so it wouldnt happen again. Hope this helps and good luck.