Thread: Stihl MS 390 Decompression?

I have someone asking a question about an MS 390 that I have for sale, they claim it should have a decompression button and it does not. Could this be an 039 with a MS 390 recoil or did the early MS 390's not have the decompression button?

I bought it as a MS 390, but now I'm not positive.

I should have done a better search before posting this, the Saw Dr. had posted this to another 390 question;

I am one of the few cheerleaders for that saw series around here. The stihl 1127 series includes the 029, 029 Super, 039, MS290, MS310, and both versions of the MS390 (with and without Decompression.) Other than a fuel line cracking issue, those saws (all of them) are as reilable as gravity. Nearly all failures are caused by owners running poor fuel in them, or physically crushing them under trees or tires. I have several tree service guys running them daily here, and they seem to hold up well.

The Stihl bar and chain book says that an 039 can run a 28" bar. That may be true, but it would be awful slow on a stock one. With a simple muffler modification, all of those saws become a new animal. You can easliy mod that one yourself in a garage using hand tools, and still keep the spark arrestor screen. I still would not suggest a regular diet of 28" bar on an 039 (390), but you could certainly do it for the occasional big tree. Plan on making sure your chain is nice and sharp and keep it that way.

I rebuilt my MS290 with a MS390 top end. When I talked to the people at Stihl Northeast they told me that I could get it with or with out a decompression valve. Which was good because I had all the plastic with no hole in it for one.

The MS290 never had a decompression button. MS390 and MS310 had decompression button fitted mid 04' (after machine number 1 62 782 388).