Welcome to the channel and thanks for the comment I did a pressure + vacuum test and changed crank seals on the ms660. I will be doing an update on the saw in a few weeks.
Do you feel the quality is close to oem? I'm wanting to build a kit 660,and will be using some oem parts like chain tensioner, hoses,clutch. I'm needing it to be reliable as a firewood saw and able to pull a 36" bar. Money,obviously is a concern, but I can splurge some. I just cant afford a new 661. I'd be around $500 all in. The kit saw is $300.
As far as I can see, quality directly compares to the OEM. Casting looks good and there were no plating defects. I was getting 190psi of compression when first assembled and am now getting higher compression of 223psi after running a couple tanks of gas though.
The saws still singing along. Compression hasn't dropped from its 223psi perch. Was running a 36" bar on it no problem, fully buried. Will get that video up in the weeks to come