Blown MS290 for $50 - Is it worth it?

Arborist Forum

Help Support Arborist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
I was told the 290 is a bear to work on. Any thoughts since I was thinking of doing the same conversion if I ever find any spare time.
It wasnt the easiest, but it wasnt too bad. You just have to remove almost everything to get the cylinder out, the plastics, fuel lines, wiring at a minimum need pulled loose and you have to remove the typical parts, flywheel, clutch (remember reverse threads), carb, more plastic, and I also had to loosen the oil pump because if the way I reassembled it. The bar stud was a unique challenge. I was able to get the cylinder off without removing it, as mine was stuck, but then when trying to reassemble it, I started with the crank and piston in the cylinder and could not get it to fit, so if you cant remove the stud, you will have to put the crank in the lower half first and try to fit the cylinder down over it. It's a pain, but can be done.

Also, the threads on my 390 cylinder were not exactly the same as the screws, but will go in if you use a little force, just dont use an impact.

The whole process sounds worse than it is.

I cant think of anything else at this time.
 
I recently changed out the top end on a 290 while upgrading it to a 390. I was able to do this without removing the clutch, and it worked out fine. It was a little tough applying the gasket sealer, but since the seals seemed OK, I assembled it all back up, said a short prayer, and the saw started and runs fine. Compression cold measures at 140 psi, and there is no need for me to use the decomp valve to start it. Yes, it was shortcut, but I had little choice. The clutch was virtually impossible to remove because it had been tightened way too tight by another mechanic and was literally frozen.

It usually takes me about three hours more to change the top end on a 290/310/390 saw than it does on any of the professional series saws. The clam shells are a bit of a pain to rebuild, but they can be upgraded. It just takes time and patience, and as FreudianFloyd said,"the whole process sounds worse than it is."
 
I bet now that I have done it, I could do it in half the time. It's just a matter of figuring out what has to come off before something else can.
 
I wish I could find deals like that in my area. People around here would be wanting $150-200 for that saw not running, right in line with ebay.
 
Back
Top