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First time 4stroke overhaul!!

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Ok Im proud of myself. Ive overhauled 2 strokes all my life (I was do it when I was 12). Now I finally got to do my 250f. I replaced the piston, checked the valves with solvent, they didnt leak but needed adjustment. Did that and put it all back together. The cam chain got kinked up on the crank gear so I had to remove the mag and stator to fix it. Got it all back together and it fired up on the 2nd kick. Im not sure why but I was kinda intimidated by it, hell I rebuild single and dual overhead cam Ford engines all the time for a living!

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Nice Job. I will hate the day when I have to do this, I am not a mechanic.

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FORD's are easy to work on, Yami's are little engines that require little hands. its much easier to work on an engine that does't sit on top of a transmission and require so much manueverablity with small tools.

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yea me and my class (auto tech.) just recently worked on an older F-250 and it was a bitch. we replaced the head, the valves, cams, and got new headers for it. but it was not easy to get back in. we had to drop the tranny out of the truck, and get the engine and the tranny connected outside of the truck to get it in there. my teacher said the new headers were rubbing against the firewall

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Yep ... cam chain replacement is highly recommended . $ 20 part is cheap insurance . You'd be surprised how much it'll stretch and then do damage to the bottom gear .

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FORD's are easy to work on, Yami's are little engines that require little hands. its much easier to work on an engine that does't sit on top of a transmission and require so much manueverablity with small tools.

I think any engine you can take out and put on a bench and work on is much easier, no matter how small the tools. And there are small parts in auto engine as well.

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yeah, well, the engine parts that are small, and fall down the block, end up in an empty oil pan, should be empty if your working on it. but generally a larger engine will have larger parts, but the pistons are a b itch to get in, you have to use a special oil filter looking wrench to compress the rings, i don't know how to on my bike, cause I have the stock piston, about 300hrs still running strong. YAMI POWER BABY. i'm going to rebuild this summer, thats why I joined this forum to gain a better knowledge of what needs and should be done

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Ok Im proud of myself. Ive overhauled 2 strokes all my life (I was do it when I was 12). Now I finally got to do my 250f. I replaced the piston, checked the valves with solvent, they didnt leak but needed adjustment. Did that and put it all back together. The cam chain got kinked up on the crank gear so I had to remove the mag and stator to fix it. Got it all back together and it fired up on the 2nd kick. Im not sure why but I was kinda intimidated by it, hell I rebuild single and dual overhead cam Ford engines all the time for a living!

You said "overhaul" but did half the top end. Wait till you have your engine sprawled across the workbench in little pieces. Much more fun. I broke a gear and damaged 4 others, so my 450 is stripped down to the case halves for significant rework. I have done this twice now with the 450 and several times with 2-strokes. 2-strokes are so easy! You really learn a lot when you have it fully disassembled. It isn't cheap either, so I won't put my bike back together for a few paydays. :thumbsup:

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