The 590 Timber Bear is a full crankcase alloy block just like the bigger Echo's are. Had mine out today working on a dead (dying) apple tree and it started second pull (been sitting for a month) with Echo Red Armor in it and Menards bar oil. Ran it for a while just to exercise it a bit and switched to my ancient Stihl 028 which is (I looked at the build date, it's 45 years old) and still screams and pulls a 20" bar (greaseable nose of course with full
chipper chain (no skip tooth for me) but I keep my loops sharp always and set the rakers ai 0.020. I guess if I needed a bigger saw, I have to 075 and the 090 on the shelf, drained of gas and oil that I could use. Problem is, at 73 years old, I'd have to have someone start them. Even with the compression releases I cannot pull them over anymore. Besides, the bars are huge. The 75 has a 4 foot bar on it and the 90 has a 5 footer 2 man. Bought them both new when I bought the 028. I often think about selling them both and then I forget about it. When I pass, my wife can give them away. Last time I had the muffler off the 028 to clean the spark arrestor screen I took a hard look at the piston and no marks anywhere. Took a wood stick and cleaned out the exhaust port too.
I actually have trouble starting the 590. It has really good compression, thank the Lord it has a compression release. of course I did fiddle with it a bit, I cannot keep my mitts of any saw, but nothing radical, just the muffler baffle and pulled the limiter caps. Echo likes to market their saws running a bit on the rich side and it has a Red Beard velocity stack and foam air filter on it as well. Not my first Echo either. Had a top handle Stihl professional arborist saw (700 bucks) that I ran over with the truck and squished it and I wasn't about to drop another 700 so I bought a Echo Top handle CS and typical me, I fiddled with it as well, Did the muffler. All the CS saws have a cat in the muffler but you can buy from an Echo dealer or Saw It Again, a non cat muffler so I did that and pulled the limiter caps and modded the top muffler baffle plate too. It runs pretty good, don't have quite the grunt the Stihl had but a sharp loop makes all the difference and it really light too. Lighter than the Stihl was. Nice saw for under 400 bucks. it is a clamshell however and not a Strato either.
I again will say the 028 runs better on the Red Armor 50-1 pre mix fuel than on the weasel pee ethanol with Stihl bottled oil in it. Idles better, and gets right up on the throttle instantly and no more draining fuel and drying out the carb and intake when I don't use it for months
Been a good saw all this time. It's only on it's second sparkplug too and the original greaseable roller nose Stihl bar as well. Of course all my saws lead a pampered life in the air conditioned and heated shop.
Would I ever buy another Stihl again. Nope. Far as I'm concerned Echo builds a high quality saw at a much better price point.