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Discussion Starter #1
While I have looked to this forum in the past for advice on this machine, this is the first time I couldn't find an answer and have posted for advice. I have a 1998 Xplorer 300 4X4 that quit on a recent outing and would not restart. Fuel and spark were good and dealership tested compression at 30 pounds. Not good. I decided to take on the project of disassembling the top end and taking a look. I removed the head and cylinder and now need to remove the piston. My question are; is there a garage trick to removing the piston pin clips and piston pin? Re-installing piston clips and pins?
The cylinder wall looks a bit scarred. As does the piston. I want to have these looked at by a machine shop for possible honing and piston replacement. This is the first step to see if costs will exceed the value of the little beast.

Thanks in advance for any assistance you all can provide.
 

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I just use a pic to pop them out and a good neddle nose to put back in and a piston pin puller to take pin out, don't hammer to much on the pin you can bend the rod
 

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i hope you can get it fixed, them xplorers 300 are awesome, they are not the fastest but they are soo light and can go ANYWHERE, I love my 850 but I miss my 300 xplorer like crazy, Good Luck!
 

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I also just use a pick or a thin nail to get it out the circlip. Place a rag or towel in the bottom end so it does not fall into the engine. Typically if you hold the piston and tap lightly on the wrist pin it will come out. I have never bent a rod doing so. You just dont want to hammer the heck out of it.

Cost of a piston with rings anywhere from 65-90 bucks
To bore out your cylinder should be around 50-70 bucks to punch it out.
Top end gasket kit will be around 25-45 bucks

If you notice scoring better to just buy an oversize piston and bore it out. You will be good to go for a long time again after that.

FYI- Typically pistons go up in .5mm increments example: if your stock bore is 65mm the next size up is 65.5mm, next bore size is 66mm These sizes determine how much "over" the psiton is using the terminolgy "the motor is .30 over or .60 over"
 

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Discussion Starter #5 (Edited)
Thanks guys, this is just the information I was hoping for. The clip is out using your suggestions and will work on the wrist pin. The piston looks scored significantly on the exhaust side so will likely replace it with the proper oversize after having it bored. This may have been bored once already so I will work with the shop on correct piston size when I know what they had to take out.
Nice to know that this may be worthwhile and that the machine is held in high regard by some prior owners. Cost estimates from PlumCrazy73Dodge look pretty reasonable so I will charge ahead.
This problem developed when I was in Arizona for a Javelina hunt. I ran it for only about 1 mile before it shut down as if the ignition was turned off or ran completely out of gas. It did not fire again after that. The shop that did the compression check indicated that I should have switched out the jets for a lower altitude. They speculated that the piston was probably hosed (and that looks to be the case here).They said that Polaris 2-strokes were notorious for this but a 4-stroke would not have been affected. I live at about 6000 feet and it was about 2500 where I hunted. Does this make sense?
 
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