Chainsaw Repair

I have not done it on a 361.

From other engines I have done it makes them touchy to start.

The usual practice is to time some cuts - advance your flywheel a half key width and time some more cuts in the same wood and see if there was any improvement?

I suspect the 361 has advancing timing on the original coil and I would not recommend advancing the flywheel any more as it is already at 26 degrees while cutting and that is getting too close to all the advance you would want? At any rate, you will not be able to likely measure any improvement.

Is there any way to tell by the coil that is on the saw, to tell if it is autoadvancing. I want to say the coil is very similar to the one on a 460.  Don't you lose some top end rpms by advancing the timing.

Most saws are timed at 26 to 28 advance .Some of the older lower compression at up to 35 which if that were done on a high comp saw all you'd get is a sore arm because you'd never get it started .

I've never done much on the Stihls but I have to some extent with  a few Macs .At about 30 advance is just about the limit of getting them started without pulling your arm out of the joint .

You could figure out by using the circumferance of the flywheel and checking by filing a little at  a time off the key how much you are advancing it .If it doesn't work put a new key back in the slot .

If your going that route.  On the cheap and free http://forums.pelicanparts.com/uploads8/free_degree_wheel1153173072.jpg

Find you one and print it out

Doing what you are doing I wouldnt use one.  I'm just a seat of the pants type though.

Not really .Circumferance of a circle is pi times diameter .So 3.1416 times 4 equals  15.57 rounded off .15.57 divided by 360 equals approx .043" .So every degree would move the mark 43 thou .So theoretically if you advanced it 1/8" or .125 it would be around 3 degrees give or take a tad .

A timing wheel is probabley easier and the larger it is the more accurate .This is not to say however you can use a 16" wheel on a chain saw .About 6 inchs would be about it .

The advance of course is from top dead center but if you were just shifting it you could lock the engine down anywhere in the rotation .

Now if you are advancing the timing using the key you have to move it in direction of rotation .Using a slotted coil the opposite .