On the Bench - Stihl Contra Chainsaw Refresh/Rebuild!

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All -

I have several Contra's; figured it's time to go through one. And since I'm documenting it anyway for my own records, figured y'all may as well come along, too.

And here she is, sitting on my workbench -





I bought the saw through a popular auction site in early January 2017. Given the condition, it appeared to be a low-hour saw, so I pulled the trigger. It came with the 21" Stihl Duromatic hard nose bar, but it was missing the dogs and chain. Original bars are out there, but not real easy to find. You can still find NOS dogs, however.

The serial number is 176143; this doesn't tell you the date, but there are a few ways to figure it out. If it had the original bar (it doesn't), these are usually date coded. I have also seen date codes on mufflers, too, but I'm not seeing one on this muffler. However, you can still get an idea of when it was produced just by going from the serial number. We know that the sand cast crankcase model production ceased on 24 June 1959 with serial number 84832. And the manual oiler (which this saw has) started with serial number 112000 which appeared sometime in 1960. And then I've seen a couple of posts from folks with saws that apparently have their original date coded bars (188587 with a February 1962 bar and 208362 has a bar dated November 1962). We also know from Stihl literature that serial number 275000 was produced in December 1963. So with a bit of redneck math, my best guess is late 1961.

Anyway, when the saw arrived, I did a quick once-over. Compression was good - right at 140. And when I pulled the muffler to take a look at the cylinder, I realized it had a broken muffler stud -- it's about 1/4" deep; too deep to weld a nut to it and just unscrew it. I fired it up and it ran fine, but I only ran it for a minute because of the exhaust leak.

So, it's time for a rebuild/refresh. The original paint is in pretty good shape, so I don't see a need to do a media blast the current paint and re-paint it. A good cleaning and replacement of gaskets and wear items should do the trick.

Scott

 

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This is the 106 cc Contra, by the way. The 137 cc Contra's are much rarer and significantly more expensive.

The original tag will denote what the saw was originally - as you can see, this one is an 1106. A 137 cc saw will be listed on the tag as an 1106 S.


As you can see from the picture above, it has the correct starter housing; the 137 cc saws came with a different housing that had more ribs and they're spaced closely together. Here's another one of my saws, this one with the 137 cc type starter housing.



You can also tell the difference between a 106 cc and 137 cc saw by the shape and configuration of the cylinder cover (137 cc covers also have a piece of asbestos or something similar attached). This is the correct 106 cc cover (although it's missing the two rubber spacers from the top); it's fairly thin sheetmetal. There is at least one other version of the 106 cc cover that's cast. A 106 cc cylinder cover will not fit a 137 cc cylinder; the S cylinder is too large.

 

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The bonnet or top cover is cracked, of course. And some of the rivets have been replaced with screws. There are high quality reproductions on the market; this saw will get one of these unless I can find a very nice OEM one.



There are at least two different styles of rear handles; the other one has black plastic on the grip. I'll have to post a picture of it.



Everything looks pretty good under the clutch cover. Still a lot of original paint.



This saw has the clutch cover with the hole in it, presumably to help clear out sawdust. It's also cracked, but I may have a good one in my stash somewhere. I will have to look for a part number on it; I'm not sure if these carry a different part number than the ones without the hole. I am also assuming that this is the correct cover for an earlier saw, but the later ones did not have the hole.