AC jag 440 rebuild

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polarisfreak46

New member
Im about to rebuild my girlfriends 97 jag 440 fan and have some questions before I start putting it back together. It blew the exhaust side piston last season and I dont want to put it back together not knowing why it blew up. It was hard to start taking 5 to 10 pulls hot or cold almost every time all season long. I wounder if it was due to an air leak but im not sure any suggestions and rebuild tips would be great thanks.
 
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dab102999

New member
Why it blew could be a tough one. What was your compression before it blew?? Among other things. Best thing is get a couple of pictures of the bad piston and get them on here and we can probably help you out. the way it looks now usually will tell you what was wrong with it the last time it ran...
 
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polarisfreak46

New member
The compression im not sure about, it looks like the ring stuck and broke up on the piston I will try to get a few pics up tomorow.
 
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polarisfreak46

New member
pics

Heres a few pics of the piston and jug I was woundering if maybe there was a base gasket leak with all of the oil on the jug
 

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gigakessler

New member
That could have been caused by a number of things....High miles, bad gas, oil pump failure....

I'm working on a panther with the same 440fan. The rod went right though the side of the block. Try looking around for a used 440 motor and swap it in. I got motor with clutches and carbs for $75. Drain all the gas, clean the carbs and premix the first tank. After you ride it check the oil level to see if the pump is working.
 
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polarisfreak46

New member
deal

man where did you find that 440 for $75 ive been looking on craigs list and ebay and havent found much of anything for that motor im getting a jug piston and rings for $200 from my girlfriends uncle Jeff from Mcbain hes a artcat cat goo roo.
 
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polarisfreak46

New member
the gas was fresh it was at the end of the 08 09 season the sled has about 4500 miles on it so I think I need to look into the oil pump situation how much oil did you mix into the tank to get your ratio.
 
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dab102999

New member
40-50 to 1 should work. 3 oz. per gallon if you only want to put a few gallons in. If your pump is working it will smoke pretty hard and might foul some plugs but at least if it ain't working you won't burn down a rebuild. Take and put a piece of tape on your oil tank and ride for 40 or 50 miles and see if you use any....you said that there was oil in the jug when you took it apart, how much was in the bottom of the block?? Made sure your pump ain't leakin' also. Simple way to do that is hook it up to your tank, spin it till oil starts to come out (droplets at a time) and then stop and let it set there on top of a rag or coffee can. Make sure pump is lower then oil tank. Let it set a long time, even over night and check to make sure oil isn't getting past. U can use a drill (I believe in reverse) also on the oil pump to bench test if it is working. I would say from what I could see from your pics lack of oil isn't the problem here. Could always be wrong though. Make sure those carbs are cleaned good and look your boots over also. If I am correct this is a fan model or air cooled?? If fan model check your belt over and fan bearings. Make sure she just didn't get hot and cause this. (had that happen to an old style Phaser one time)
 
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toddspolaris

Member
looks like possible detonation on the exhaust side caused by an overheat situation, make sure fan is working proper and no mouse nests anywhere to restrict air flow, Usually, if oil related problem both pistons will go at the same time and usually stick really tight in cyl.Good luck
 
bouncer

bouncer

Member
Looks like you might have caught the ring on the exhaust port. Check the other cylinder and make sure you have a good chamfer on the ports. Good luck.
 
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jimfsr

New member
Detonation is ignition of the fuel by something other than the spark plug. Can be caused by high heat (lean or overheating), hot carbon on the piston top, spark timing thats way off (something bad in the ignition system) or really poor fuel octane. High compression can cause pre-ignition or detonation with low fuel grade. This is how diesel engines operate, no spark, just real high compression and the right fuel.
If detonation is present you can sometimes hear it, it will sound like a pinging or knocking noise in the motor. If you ever hear it, change RPM or shut it off before something melts.
 
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polarisfreak46

New member
Thanks for all the info guys just wanted to let you know I found that the piston ring pin broke allowing the ring to spin and catch the exhaust port. Why did the ring pin break who knows. I think I read somewhere it could be a bent rod but Im not sure any additional info would be great.
 
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Polariscatgrabber11

New member
Jake if I were you I would junk that MOTHER!... I probably blew it up carrying my fat body on the back of it! junk arctic "fag" anyway tell your ol' lady to buy a REAL sled and then a REAL truck!...HAHA someone dident teach her the right things in life, drives a ford rides a cat...man....
 
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rkw

New member
busted ring

looks to me as though you broke a ring. Typically from not replacing the rings on high mileage machines, or lower mile machines with improper lubrication. you can replace the cylinder and piston but you also need to be aware of the junk that got down in the crank case when she blew. Good luck.
 
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