Yep, 660. Gas was in it awhile, not sure how long, but I've never had a problem before and always run e-free premium about 40 to 1. Need to decide if I should get another big bore for it, not sure the brand on it now, or aftermarket. OEM is a little high for me. Not set up to pressure test it.
There is some decent aftermarket stuff out there...I guess it just depends on what you want. Hopefully its just the top end and the crank/bearings are still OK. I'm not nearly the saw guru that some of the others on here are. I know Armbru84 usually has some 660 parts laying around...if he doesn't then I'm sure he would know where to point you...
I have a decent amount still but only one piston and cylinder. I built a MMWS cross cylinder and put it on a 660 I built for amateur cutter and it runs really good. You have to pay attention to the bevels on the ports though and I know that can be a pain I can try to track you down a used oem cylinder if you want. Just let me know.
Not straight gassed. I guess I learned my lesson leaving gas in saws. I would guess it sat 6-8 months with the gas in it, maybe June last year. My bad, but have to move forward. Purchased the saw from a member on AS 6-7 years ago. I know it has a big bore kit with no base gasket and he said it tested at 200psi when he sent it, almost more than I can handle. I've looked at MWP big bore and Meteor kits (same price) and I think they have good reputations from members. I also think it was a MWP kit I put in my best friend's Husky 261 8 or so years ago and it still runs great. Any advice is appreciated and at least it's not the most expensive mistake I've ever made.
An air leak can cause lean condition as well. I’d get the pressure test kit and test that too before running too long with a new cylinder on there.
^^^^^ this . Don’t put money and time into changing the P&C until you can determine the cause of the failure . You can pick up a mity-vac kit at very reasonable prices on ebay . You can use Gorilla tape for block off plates on the intake and exhaust .
huskihl may have some decent thoughts on AM kits. I don’t know a ton about Meteor but have heard good things.
The only AM kit I trust right now is the Cross MMWS kit, but it needs the center of the exhaust floor and roof beveled better or it'll hang a ring. The one you have may also clean up. But you need to find what caused it. Either an air leak, tune, or the gas separated from the oil while sitting. Or like John mentioned, the screen is plugged. If you'd like, and if you end up going with the Cross kit, you could have it sent to me and I'd bevel the ports better and ship it to you Just pay the added shipping
The FT cylinder that came on them are a crapshoot, depending on which one you got. The plating doesn't like staying put. Also, I've seen at least 2 different cylinder kits sold as part of the kit. I have a couple. Definitely fun projects
So far so good with mine...not a ton of time on it though. It looked pretty good other than the plating that was peeling inside the ports when I got it...I figured things weren't "prepped" for it to stay put in there anyways...so ground it out while cleaning the ports up a lil bit too. And it had the sharp edges on the ports that needed chamfered too. Put it together sans base gasket...low 20s on the squish...runs pretty good...put a 32" bar on, it pulls that well. But it felt like a dog after running Armbru84 s "juiced" 084 with a "short" bar on it though...
Looks like it scored right across the rings. That is a shame. The Meteor pistons for the 066 Stihls I think are pretty good. I have one I installed in one of my saws and have been milling with it and so far it has held up real well. I would also try and save the cylinder. A lot of the time it is just aluminum transfer and can be removed.