Stihl Contra - On the Bench - Refresh/Rebuild
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Continue to make slow progress here. Now have 4 (!) Contra's completely apart, so I'm reassembling them all now. Doing it like an assembly line instead of one saw at a time.
The bottom of the saw serves as the bottom cover to the gas tank; as you can imagine these get pretty beat up. And one had some pretty significant corrosion. These were all blasted with aluminum oxide at lower air pressure. Then painted with self-etching primer. And the gouges, chips and scratches were bothering me, so I mixed up some JB Weld and did some filling in. Next step is to sand it all even and then prime again.
I also have a few 6 shoe clutches that I picked up recently; at least one will go into one of the Contra's. I also scored a nice NOS piston and cylinder from an AS member. Yep, 137 cc's. Seen below pictured next to an original 106 cc piston and cylinder.
Scott
The bottom of the saw serves as the bottom cover to the gas tank; as you can imagine these get pretty beat up. And one had some pretty significant corrosion. These were all blasted with aluminum oxide at lower air pressure. Then painted with self-etching primer. And the gouges, chips and scratches were bothering me, so I mixed up some JB Weld and did some filling in. Next step is to sand it all even and then prime again.
I also have a few 6 shoe clutches that I picked up recently; at least one will go into one of the Contra's. I also scored a nice NOS piston and cylinder from an AS member. Yep, 137 cc's. Seen below pictured next to an original 106 cc piston and cylinder.
Scott
NOS 137cc jugs? Maybe unicorns do exist!
That's awesome. Please keep this thread going with progress updates and LOTS OF PICS!!
That's awesome. Please keep this thread going with progress updates and LOTS OF PICS!!
andrethegiant70
Addicted to ArboristSite
Very nice work, BP. Stunning that you laid your hands on FOUR Contras!
NOS 137cc jugs? Maybe unicorns do exist!
That's awesome. Please keep this thread going with progress updates and LOTS OF PICS!!
Jon - they do indeed exist. But they are quite difficult to find and they are not cheap!
BTW - someone harvested the rings off the 66 mm piston; does anyone know if the rings are the same for the Contra S and the 090? Bore is the same, but I know on the 070 and 106 cc Contra the rings are different -- thicker on the Contra.
Thanks,
Scott
ATG -
They are a lot easier to find here than they are in the states. I have 6 now; hope to take about 10 back with me when I leave Italy next summer...
Scott
Hi Scott
The Contra S piston rings and the 090, 090AV piston rings are the same (1106 034 3010 60mm*1,5mm). Only the piston rings from the 090G are different (1106 034 3003 58mm*1,5mm)
That's excellent news! I was worried that I was going to have trouble sourcing these.
Thanks
Scott
victorroadster
ArboristSite Member
the contra s i am considering buying has the round tube going from handle to the hand grip at the front,how many variations of the contra s did they manufacture,regards phil.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
Is it a full wrap handle like the one posted on this page? http://www.arboristsite.com/community/threads/stihl-contra-info-sharing-thread.81574/page-23
Or is it similar to the one posted here? http://www.arboristsite.com/community/threads/stihl-contra-info-sharing-thread.81574/page-44
Scott
Attached pic is a better one of the early clutch cover that substituted for a true full wrap handle.
Also, just in case you're not familiar with the Contra S - they are quite rare and usually quite expensive, too. A few areas to check - the clutch should have six shoes instead of three; you can upgrade to the correct six shoe clutch, but it's not very cheap. The cylinder is 66 mm, of course, on the S, and the top of the S cylinder looks different - see the pic earlier in this thread for a comparison. The 66 mm jugs and pistons can be found, but expect to pay at least $500 for an NOS one. The cast metal cylinder shroud is specific to the S and incredibly difficult to find, so if the saw doesn't have this, it should take a huge hit in value. No idea what one would sell for if you could find one.
Good luck,
Scott
Also, just in case you're not familiar with the Contra S - they are quite rare and usually quite expensive, too. A few areas to check - the clutch should have six shoes instead of three; you can upgrade to the correct six shoe clutch, but it's not very cheap. The cylinder is 66 mm, of course, on the S, and the top of the S cylinder looks different - see the pic earlier in this thread for a comparison. The 66 mm jugs and pistons can be found, but expect to pay at least $500 for an NOS one. The cast metal cylinder shroud is specific to the S and incredibly difficult to find, so if the saw doesn't have this, it should take a huge hit in value. No idea what one would sell for if you could find one.
Good luck,
Scott
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chainsawman53
ArboristSite Lurker
Good afternoon,
Nice job, you might like this idea.
https://www.ebay.com.au/itm/153652623836
Regards from down under.
Garry Kantoks
Nice job, you might like this idea.
https://www.ebay.com.au/itm/153652623836
Regards from down under.
Garry Kantoks
