MS250 for $75, no compression...sure, why not

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There are preassembled MS250 engines on eBay costing little more than kits. I suggest you check into them.

Anyone had any hands on running experience with that aftermarket cheapo kits and/or engines for Stihl chainsaws?
I see aftermarket short block MS250 engines for like $40 on flea bay and kits for $39.
 
got it torn down last night.

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Overall, it doesn't look like it was run very much.

The piston looks like it had melted at the edge, before it blew a hole through. The cylinder appears serviceable.

It looks like once they figured out they had cooked the saw, they left it out in the rain. Lots of water in the cylinder, and a fair amount of surface rust in the muffler.

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I got all the plastics pressure washed and then all of it reassembled.

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While I had it apart, I went ahead and modded the muffler, on the port side and the exhaust fins, I didn't touch the baffle.

After filling with some gas, it cranked after about the 3 pull. It would run a little, then die. I did get it to spin up to about 10k RPM once, and nothing blew up, so yay for that. I was hoping that the carb would be good, and after playing with it for 30 minutes, I've decided it needs a rebuild as well. Bought a kit for $2 shipped from hong kong, so I'll work on that when it gets here. In the mean time, I'll take the carb off my other MS250 and see if I can get this one running well.

Total time was about 3 hours to tear down, wash, and reassemble. That peppered with changing the oil in the van. I then spent about 30 minutes tring to tune a carb I knew ought to be rebuilt. I can see why a pro would hate this saw from a repair perspective where time is money, but for a homeowner/hobbyist I think it would be fine for tinkering with, nothing involved was particularly difficult nor overly time consuming. Caveat being that I have nothing to which to compare it.
 
Clean the main bearings with compressed air. I just reassembled an MS250 with the same kit and the bearings had crud in them making them feel notchy as they spun.

I noticed the grittiness of the bearings. I lubed them up with 30wt and they smoothed out a bit, not perfect, but better than dry.

I’m not sure I’d give that much for a saw with a hole in its piston like that. Gotta be more damage than whats visible, it’s a pile of parts worth maybe $50, if the bar and chain ain’t shot like the piston. :cool:

If I had more time to evaluate the saw when I picked it up, I would have offered $40, but I was in a rush. The bar and chain are both in good shape, bar still has most of the paint.
 
The ms250 is a pretty easy saw to work on in comparison to others. Try working on ms390...
Anyhow i have a roached out ms250 that i got disassembled in a box that has way more hours on it than it was designed for, with a cheap golf piston, and it has been cutting cord after cord for over a decade.
If you intend to use it to any capacity, i would replace the intake boot, impulse line, and fuel line and throw a kit in the carb. Getting a lot of money into a cheap saw, but just speaking from experience what will let you down not if, but when.
 
My 290 has a 100 dollar kit in it and my craftsman had a 20 dollar kit in it and so far they both run great. The hyway kit came with some odd bolts that didn't tighten the bottom to the top very well or at all and the Chinese kit came with a wrist pin about a quarter inch to long. Take your pick. In the end it's up to the installer to make it work.

When my 028 comes due I may try a tecomec kit or may just say eff it and buy a China kit Idk. It's the difference of 100 dollars and i don't have any proof that it's worth it.
 
Better shot of the piston.

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Robbed the carb off of my other MS250, and had this one running again with about 10 minutes of tuning. Just need to wait on the carb kit to come in from china so I can get the donor running again.
 
Better shot of the piston.

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Robbed the carb off of my other MS250, and had this one running again with about 10 minutes of tuning. Just need to wait on the carb kit to come in from china so I can get the donor running again.

Piston port!
 
Picked up a 14" bar and chain, and 3/8 rim/sprocket to go on this one. My dad has a 16" MS180 and 20" 026, this will give me a 14" and 18". Think we have things pretty well covered.
 
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