Sunday, February 10, 2013

Re-cording your Stihl MS170 Chainsaw

Sorry I haven't written in a little while. These first three weeks of February, I am working four days a week at Howie's Saw. This means some fiscal resources are coming in, but I am not accomplishing too much at the homestead.

As I described in a previous post, I managed to plug up the air filter on my chainsaw so completely as to render it inoperable. In discovering this, I had to work the recoil start to the point that the rope broke. My first attempt at replacing it with a length of multipurpose cord was successful until I actually arrived in the bush, when it broke immediately. I put the chainsaw away that day and didn't get around to re-cording it until yesterday.

One other thing that has kept me from accomplishing much is a suspected fracture in my foot. This is the second time this has happened to me, the first being back when I was training much more heavily in Aikido. I woke up in the morning, thinking I had twisted my ankle and hobbling a little bit. The pain grew worse throughout the day, and moved down into the outside edge of my left foot. By the following morning, the pain was very intense and I spent much of the day just sitting or laying down. Grandpa was kind enough to produce a cane for me (that he's never used), which greatly aided my mobility.

I worked the week with the cane, and by the end was back to hobbling and then limping. Now the pain seems to have moved back to my ankle in the form of some stiffness in the mornings. My foot is still noticeably swollen, but I think it will be okay.

In any case, yesterday I felt good enough that I wanted to bring in some more firewood. I began by first cleaning some snow and sawdust off the saw.

Next I removed the cover. You simply rotate the black catch counter-clockwise on the back of the saw, and the cover lifts up and back. I find that engaging the choke helps quite a bit, as the switch catches on the cover otherwise.

There are four screws holding the recoil mechanism in place. Two at the rear of the saw, one beside the oil plug, and one on the kickback brake. The one on the kickback brake is different from the other three, but that's obvious once removed. A Torx T27 seems to be the best fit for these screws.

Pull the kickback brake up and off of the recoil portion of the case.

 

You have to remove the oil cap and the gas cap completely to get the recoil mechanism off of the saw. I found a pair of needlenose pliers worked best for this. The caps are held to the saw on a short length of string attached to a half-moon of plastic grid. Grasping a corner of this grid allows you to twist it sideways and pull it through the narrow threads of the respective reservoirs.

The recoil mechanism is wedged under the left-hand handlebar, and requires a bit of firm wiggling to pull it free. I've done it a few times now, and have a better feel for it.

Now you have the mechanism completely separated. You can likely see your old string there and how it enters the side of the spool and is then knotted to prevent it from pulling out. Unspool the string and prepare your choice of new cord. I found that it was easier to thread the new cord through the spool from within the groove and then pull it up and away from the mechanism, rather than the more accessible hole already facing outwards, and then trying to get it to turn and come out in the groove. Grandpa supplied a length of nylon cord for this step. Once it was threaded through, I put a knot in the end of Grandpa's cord and attempted repeatedly to get the lighter to melt it slightly to prevent it from unravelling.

I wound a few wraps onto the spool (careful to go in the same direction as the original). The exit hole through the casing should be your guide here to which direction to go. Don't make the same mistake I did with my generator - it is VERY frustrating to obey Murphy's Law on items that take some time to redo.

Turning over the mechanism once you've wrapped the cord and have it extended outside the case, you can re-attach your handle. Currently the cord passes up the shaft of the handle, then makes a 90 degree turn and comes out sideways. I couldn't re-thread it in this fashion, so I simply made a large knot on top - old school!

Try to make sure there is still a slight amount of tension in the cord - this will prevent the cord from falling off the spool inside the saw in the future.

Do a few test-pulls, to work out the kinks and be sure there is still some tension there.

Reverse the order of operations to get that mechanism back on the side of your saw.

Don't do something dumb like I would do -- Keep the saw itself on its side until you have a chance to replace the gas and oil caps and tighten them down. Washing chain oil out of pants isn't that impressive for your spouse, especially when you have to carry your own water to the washing machine!

There! You're all set! Pull the cord - and - if you're like me - Grandpa's never-fail cord breaks on the second try.

Repeat this whole process with a third cord that you've rigged up by braiding three smaller cords together. Now you're in business!

I then managed to start up the tractor (n.b. Diesel starts about tenfold more easily in ten below than twenty below, i.e. about tenfold more difficult than at ten above.).

I headed out to the bush to cut down my firewood trees. I carefully parked the tractor at a safe angle from the first tree I intended to cut.

Carefully lining up the tree to be sure it fell at WORST thirty degrees away from the tractor, I was struck by how I managed to actually cut it so it fell directly towards the tractor.

Being the stoic that I am, I didn't even give it a second look to see how badly it had crushed the old Yanmar. I moved on to the second, and then third tree, felling them also towards the trail.

Returning to the tractor, I was relieved to see that my ability to judge direction was matched by my ability to judge distance.

Yes, the tree fell directly at the tractor. But it fell at least six feet short of hitting said target. Oh happy day.

I ended up cutting it in half and skidding the lower portion far enough up to be able to grab both halves and skid them back to the yurts.

Donna informed me that Kenny wanted me to take them to town to visit the Lakehead University exhibits at Intercity Mall. Kenny never wants me to take him anywhere, so I had some skepticism. I told her I wanted to try to grab the other two trees first, and headed back to the bush.

These ones went slightly more smoothly. I brought them up in three pieces, told Donna to get Kenny ready to go, and then was able to park the tractor, refill it with diesel, refill the saw with oil and petrol, sharpen the saw, and change my clothes. All in the time it took Kenny to make a "deposit" in the thunderbox.

We were off, and I have to confess, I felt not a little shell shocked to be out in the bush by myself one hour, and then in the midst of the shopping mall surrounded by noisy, strange crowds, only an hour later.

 

1 comment:

  1. Glad you enjoyed it. The MS170 seems to be a great value. My rigged up cord broke again, but because of the troubles I've had with my little Chinese generator, I had extra pull cords for it, so I swapped one of those onto it, and it seems to work great.

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