Been very frustrating trying to get this Tree Guy's MS660 off my bench. Knew it had a bad seal, so I ordered seals at my local shop Monday, they told me they would have them on Tue. I didn't trust em, so I also ordered some from FL, they were supposed to arrive by COB Fri.
So here I am this AM, still with no seals. At 1:04 I go on the computer, and it says the seals from FL were delivered at 1:00! I run to the MB and there they are, and the mail truck is just 2 doors down!
So I put a new seal in, and the saw sounds almost as bad, so I do a pressure check and my new seal is leaking. Luckily, I ordered extras, so I carefully installed another. Saw still won't run right, but when I test it, it holds both pressure an vacuum. I'm ready the throw the saw in the garbage, and I decide to put the spare Asian carb I have on it … PROBLEM SOLVED, it runs just fine.
Now I think I'm done and go to put it all back together and I notice the metal driver on the oil pump worm gear is broken off where it goes into the clutch. Did not notice that when I took it apart. I've got them for 460s, but not for 660s. Got to order parts again, but at least this one is a simple fix. Just frustrating having this saw on my bench for so long.
(Note: On Monday I called 3 local Stihl shops, and none had 660 seals in stock!) I just have to conclude they are all really just lawn mower shops that also sell saws.