MS290 starting issue

So, this thread ain't dead yet!

I have not been able to fully duplicate Kimberly's issue with the saw jumping up off the ground but I have been able to rectify the starter locking up and made a few improvements that I feel noticeably reduce the effort required to start "The Beast".

I'll see if I can scrape up some pics and update the thread during this week. I got the muffler mod done too but...... managed to snap one of the exhaust studs (common with these) in the process. So a bit of a delay while I wait for parts but no biggie.

 

Actually it was the locknut that seized to the stud and broke the last 8mm or so off it. These are not threaded into the cylinder casting either. They have big squareish heads that fit in a slot so if you break one, no biggie, toss it and throw a new one at it.

Starter was locking up when fully extended because the spring was overwound. Backed her off a couple turns and now it's right as rain. Converted it to dual pawls and an ElastoStart handle too so now it pulls much smoother with less wear and tear on the mechanicals.

 

You....Are...The....Man...... MasterMech

 

So, here we have a plain old starter assembly as they come from Stihl for this model. One pawl, standard handle. Nuthin' fancy.





Comparison of the elastostart handle and the standard version. These handles have either a rubber grommet or a spring inside to absorb the bump of each compression stroke. This stores energy as you pull the rope and that energy is transferred rapidly to the flywheel once the engine pulls over the first compression stroke. The boost makes the subsequent compression events that much easier to pull through.





And the dual pawl setup. Which balances out load on the rope rotor (pulley), by cancelling out radial forces on the rotor bearing surface and reducing any axial thrust. This should help keep friction to a minimum and allow more of the human energy to be transferred to the flywheel for easier starting.



Here she is, complete.

 

And for the muffler mod, we have here the muffler as it comes from la factoría. Note the two tiny tic tac size holes and very, very restrictive deflector exit. These poor saws are meant to breathe a lil' better than this but Uncle Sam has his boot on her neck for sure.



The ovals are for exhaust to exit and the round holes are just where the muffler mounting studs go.



Yeesh. Even a baby 42cc Poulan has a less restrictive muffler than this.

But with a little common sense and good ol' Yankee hackery, we can screw anything up so here's what I've come up with so far.



This is slightly different than what I have been doing on these for awhile now but I went god route for a couple reasons. One, it's fast and real easy to do. Two, there is little if any discernible difference in the noise output of our tree slayer from it's stock configuration. You can get even more out of these by grinding out the inner baffle or bypassing it entirely by adding holes in the dimpled area but that will significantly change the dB output and tone of our saw and make it a tad more finicky about it's carb settings at idle. Neither of which are acceptable in this case.



I also did the deflector a little different in this case as I wanted to see how much area I could get without taking a bunch of material off the front and significantly changing the exhaust direction. I think this gets us plenty of exit port size for this saw and is a more subtle change from stock than cutting away the beveled section of the deflector.

 

I modded a pair of slippahs......they have your name on them......I need a flat rate box now......

 

Modded slippah feed thongs.....a Wytheville speciality