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Discussion Starter · #1 ·
Hey all,
I fianlly torn down the engine out of the Trailcat last night, after leaning her out a few weeks ago....D'oh.
Anyways, the piston is cooked on the top but no holes, just flatened and rough, the rings are now fused to the pistons too.
I am having a hard time getting the wrist pin out though. Any tips on how to get it out? I haven't put heat to it yet, is that OK to do?
 

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Discussion Starter · #3 ·
Yes, but how do you do that without bending the connecting rod, 2 person job??
I'd rather not have to take the bottom apart just to replace a piston.
I soaked it really well with "Bolt-out" last nite, and didn't try it yet since.

BTW. I think that this machine would be way better with a AC - Suzuki 500 fan with dual carbs, think I'll try to find one from a wrecker. The machine is light with good handling and ride, but this 440 single sucks for power and overheating, even when jetted properly. Needs new clutch too, Powerbloc just don't cut it.
 

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Yeah, you definately don't want to knock it to hard or else you can bend the rod. But I've had really good luck with placing a socket (the same size or slightly smaller than the pin) on the pin and lightly TAPPING it out with a hamer. They usually come out nice with this method.

When you go to put your new one in, be sure to coat it, and the inside of the piston hole with two stroke oil. You should be able to slide it in using just your fingers. ( I know that sounded dirty....but in this case its not :--)
 

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get a piece of 3/8 or 5/16 ready rod. put a nut and washer that is a tiny bit smaller than the pin diameter on one end. slip it threw the pin and on the other side put a socket or pipe that the pin can fit in. than use a nut with washer and start to tighten the two nuts and it should come. i would even use a small impact gun. then you have no worry about bending the rod or wrecking that bearing.
 

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That sounds good, Madcow. I was wondering if there was a way he could use a bearing puller to put pressure on the centre while holding the rod with the arms. I think your way would work better, though.

Jacqui.
 

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Discussion Starter · #7 ·
Madcow...nice man, that's a great idea. I'll try it Tfins way 1st and if that doesn't work then yours definitly will...thanks.
I try putting a little propane heat to it before as well. The penetrating fuilds been in there since last night, so it might come out with a tap or 2 anyway.
Thanks everybody...what a wealth of knowledge and creativity here on TUSF.[:)]
 

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Carefull with the torch,you every see penetrating fluid burn,it,s like gas,
Go with madcow way,works great,No fear of damage
 

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Dude this may sound crude, but it works. Get a C-clamp with about a 4-5 inch spread. Insert a small socket into the wrist pin area so it will pass through the piston but not the wrist pin. Get a block of hardwood and bore a hole about 3/4 to 1 inch in diameter in the center but not all the way through. Put the block of wood over the side of the piston so the hole goes over the wrist pin, apply the C-clamp to the wood and the socket and turn the clamp. Sounds like I dont have a pot to pee in, but it works and its free if you have the clamp laying around. LOL.
 

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i wouldnt use the torch. if the engine is at room temp. pour ice water threw the wrist pin whole slow for a few minutes.. the result is the same shrink the pin or grow the piston.
 

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I use the heat method. Just warm the piston and push the pin out with a wooden dowel.Use the minimum heat nessesary.The pullers the guys suggest sound like they would work great also.
 

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Discussion Starter · #14 ·
GOT IT!! 10mm soecket and extention, and tapped it out very carefully.
Probably came easy sitting in penetrating fluid for 36 hours.
Thanks everybody...all great ideas.
Kev
 

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I use to use the socket and hammer way untill I got a wrist pin puller. Works like the way Madcow was discribing. The only way to go. Riley
 

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Discussion Starter · #16 ·
I could not imagine rebuilding enough engines to justify a tool like that.
You must rebuild lots of engines Riley.
 

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This is the method I used.

Also, the easy way to get them in:

leave just your wrist pins in the freezer for a few hours. Then, when you reaassemble, they will slide easily into the piston.

-Dean

Originally posted by MAYDAZE
[br]Dude this may sound crude, but it works. Get a C-clamp with about a 4-5 inch spread. Insert a small socket into the wrist pin area so it will pass through the piston but not the wrist pin. Get a block of hardwood and bore a hole about 3/4 to 1 inch in diameter in the center but not all the way through. Put the block of wood over the side of the piston so the hole goes over the wrist pin, apply the C-clamp to the wood and the socket and turn the clamp. Sounds like I dont have a pot to pee in, but it works and its free if you have the clamp laying around. LOL.
 

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Hi 500fasenuf to answer your question yes I do quite a bit of motor work. The wrist pin puller was only about $35.00. Working on sleds is how I fund my racing. Good luck on your motor. Riley
 
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