MS 361 advice needed

[dswensen]

Let me start by saying I don't get to saw very often. :msp_crying:

Over two years ago, I bought an MS 361 because I heard they were going to stop making them. Ran it once in a large maple for about 1 tank of fuel, then put it away. Got to run it again yesterday in old dried oak for about 1 more tank of fuel - now it has two tanks total through it.

When I bought it, the dealer (a good one) set it up for me, but yesterday, it seemed a little lean - just BARELY four-stroking out of the cut and it SEEMED to run awfully fast. Went to adjust and the H screw is maxed out CCW against the limiter tab. When I got home, I pulled the muffler just to be sure, and the piston looked perfect

Question: As it's now out of warranty, and as I'm a little uncomfortable at how fast it seems to run, should I pull the limiter on the H and richen it up, or should I wait as it's obviously not broken in yet?

One more bit of data; the first time I ran it, I was using regular fuel (mixed properly), yesterday I was using premium fuel mix. Does premium cause the saw to run a little leaner? If so that seems backwards to me.

 

[Simonizer]

If it sat for a year without running, the fuel-pump and/or metering diaphragm might have stiffened up a bit reducing fuel delivery. I would take it to the dealer and have him go through it. It is too nice a machine to risk running lean. When you get it back, run it a bit every 2 months or so, it is good to keep the juices flowing.

 

[rob066]

My 361 runs similar to yours. I tried mine in the cut. I put it under load and released it from the cut and it barely four stroked. It didnt seem to four stroke nearly as much as my Husqvarnas. I wasnt worried though. I felt comfortable that my saw was atleast four stroking. My saw is stock. You probaly cant hear the 361 four stroking much due to the restricted muffler vs the hollow muffler of the Huskys

 

[roostersgt]

You could drain the fuel and add some of the pre-mixed canned fuel and try that. It has no oxegenated fuel and may make it run richer. Worth a try anyway.

 

[indiansprings]

I would follow Simon's advice, it is right on the money. If your not highly confident in your tuning skills, I wouldn't run the saw until I took it to my dealer and had him set it with a tach. It is way to nice of saw to learn tuning on. It's not worth frying it to save a few bucks.
With the alcohol content of todays fuel they tend to dry stuff out quicker. It's best to exercise any equipment. In the military we did it on a schedule. I've carried that over to the farm, I've got a little notebook and keep track of each piece of equipment and start it up and run it on a schedule, if it drives, I make sure to drive it at least a quarter mile before putting it back up, lubes all the seals.
If you leave gas in your saws for extended periods use a good mix like Stihl Ultra that has good fuel preservatives and conditioner in it.

 

[SkippyKtm]

If it sat for a year without running, the fuel-pump and/or metering diaphragm might have stiffened up a bit reducing fuel delivery. I would take it to the dealer and have him go through it. It is too nice a machine to risk running lean. When you get it back, run it a bit every 2 months or so, it is good to keep the juices flowing.

I would follow Simon's advice, it is right on the money. If your not highly confident in your tuning skills, I wouldn't run the saw until I took it to my dealer and had him set it with a tach. It is way to nice of saw to learn tuning on. It's not worth frying it to save a few bucks.
With the alcohol content of todays fuel they tend to dry stuff out quicker. It's best to exercise any equipment. In the military we did it on a schedule. I've carried that over to the farm, I've got a little notebook and keep track of each piece of equipment and start it up and run it on a schedule, if it drives, I make sure to drive it at least a quarter mile before putting it back up, lubes all the seals.
If you leave gas in your saws for extended periods use a good mix like Stihl Ultra that has good fuel preservatives and conditioner in it.

Give the OP a break, He doesn't sound like he's stupid! By his description it sounds like he's capable of tuning his own saw. Pull The limiter caps trim the tabs and reinstall them, turn the H screw CCW until its running like it should: 4 stroking out of the cut and 2 stroking while its in the cut and you'll be fine. Its time to take off the training wheels and let the poor guy tune his own saw!:msp_tongue:

BTW, using premium fuel VS. regular won't make a difference as far as it running lean.
Your much better off running premium over regular anyway, as 89 octane is the factory recommended minimum.

 

[dswensen]

Appreciate the help!

I pulled the carb and diaphram looked like and felt like it was new (I always drain and run dry before I put the saws up).

I pulled the caps and trimmed the tabs. Richened the H side up about a 1/8 turn and now it four strokes like I think it should. Might be giving up a little performance if it's on the rich side, but I like the insurance.

Thanks for the thoughts - I'm no expert by a long shot, but this is one I was pretty sure I could solve on my own with good advice.

Thanks for the explaination on the octane difference too.

 

[Anthony_Va.]

Sounds good that you got it running right. They sound kinda lean for the RPM to me also. When mines tuned right, it still sounds like it's screaming. Just the way the muffler sounds. It's easy to fool you.