Crafstman/Roper 3.7 Bar Replacement

[gizmodo]

I found one of these saws during our curbside cleanup last spring. The model is 917.353770. I got it running by cleaning the carb and putting a new spark plug in it. It runs great but doesn't cut very well. The chain on it is an Oregon .325, .050 with 74 drive links. I am going to order this chain: https://www.amazon.com/dp/B001SCTWIK

I'd like to replace the bar as well since it is pretty worn out. However, I'm having a hard time determining what bar to get. Will this one work? https://www.amazon.com/dp/B001SCINBW

Any other suggestions would be great. Right now I'm not looking to convert it to a 3/8 inch setup.

 

[BDM53ENT]

Wish I could help on it. I ran mine today and its become one of MY favorite little saws. Im fortunate there is a small old timer still in business in town that cut a chain for mine. Good luck with it, its worth the trouble to get going Imo

 

[BDM53ENT]

Sorry, went stupid trying to post a pic but here is mine.

 

[rburg]

When my uncle replaced the bar on his I believe he used a home lite bar as a replacement.

 

[dougand3]

You can match your bar to the pics embedded in this chart. http://www.acresinternet.com/cscc.n...e39f46cf37dbe4a088256e0d0051dd49?OpenDocument
IIRC, the Roper 3.7 takes a D176 mount. Get that pic and compare to your bar. The Amazon bar above won't work - that's a D025 Stihl mount. The last 4 characters of an Oregon bar is the mount. You need to match your bar slot width and oil hole location.

 

[dougand3]

Chart:

 

[Modifiedmark]

If I remember right and I think I am, a Poulan/Echo K041 mount is the closest to the original Roper bar mount and is probably the best to use with a .325 pitch chain.

 

[gizmodo]

Good stuff guys thanks! I'll check the bar tomorrow and report back what I find.

View attachment 539138
Sorry, went stupid trying to post a pic but here is mine.

Interesting, mine looks nothing like that.

 

[gizmodo]

It looks like the best match for this is the K041/A041 mount. So that means I'm looking for the 180SLGK041 bar, correct? Are there any other options for bars out there?

Also, I see a lot of the chain/bar combos have a chain with 72 drive links. My chain has 74, I counted about 10 times to make sure. Does that change with the sprocket on the clutch?

 

[Modifiedmark]

It looks like the best match for this is the K041/A041 mount. So that means I'm looking for the 180SLGK041 bar, correct? Are there any other options for bars out there?

Also, I see a lot of the chain/bar combos have a chain with 72 drive links. My chain has 74, I counted about 10 times to make sure. Does that change with the sprocket on the clutch?

I might have been mistaken, I was thinking the original bar oiled through the adjuster holes. The K041 is that way, it does not have a separate oiler hole.

Give me a measurement from the top of the bar slot to the bottom of the oiler hole please..

 

[gizmodo]

Well that's a bummer. Of course it wouldn't be that easy!

 

[Modifiedmark]

I got a chance to investigate this a little more today. Seems my confusion is that the saw you have is a later 3.7 Roper then the one I did years ago and must use a different bar. I'm still fairly certain I used a K041 on that older Sportster style.

The good news is by your measurements A D176 bar will bolt right up to your bar mount pattern. The bad news is I don't think there was a D176 bar made for .325 pitch chain. If there was I never seen one. Also the bar mount is a bit large to run a 7 tooth .325 pitch sprocket.

So at this point I need to know what you have for a sprocket, a spur sprocket or a rim and drum setup and how many tooth sprocket you have now. According to the IPL at sears it shows a rim and drum setup.

If you have a rim setup it would be a easy switch to convert it to 3/8 pitch chain then you could just bolt on a D176 bar.

If you have a .325 pitch spur sprocket and your stuck with .325 pitch chain, your down to using a hardnose bar or buying a power match type bar and changing the tip over to a .325 pitch tip.

 

[gizmodo]

It is a rim and drum setup. I pulled it off tonight and the part "gear" the chain goes into says .325 - 8. Any idea on what part numbers I need for the conversion? Would there be any value in converting to a 20 inch bar?

 

[Modifiedmark]

I don't have part numbers right this moment, but I'll guess it uses a standard size Oregon rim sprocket.

As for what length bar, it don't matter that much what ever you prefer and think you need for length.

Most D176 bars will use 60 Dl for 16", 66 for 18" and 70 dl for a 20". That is for 3/8 chain.

 

[gizmodo]

Thanks! I think I am all set. I am going to order the following (for whatever reason 20 inch bar/chain was cheaper than 18):
Oregon 68210 7-Tooth Standard 7 Spline Power Mate Rim Pitch , 3/8"
Oregon 20-Inch Vanguard Chain Saw Chain Fits Homelite, McCulloch, Poulan D70
Oregon 200PXDD176 .050" Gauge 3/8" Pitch 20" Pro-Am Bar

 

[Modifiedmark]

Yeah sounds like it, only thing I would change is the Vanguard chain and order a 72DP for a semi chisel or a 72LPX chain for full chisel.

I don't mind the vanguard chain that much if I already have it, but wouldn't order it if I had other choices.

 

[gizmodo]

Thanks for the heads up. I changed to a 72LPX. I was looking at that one but was concerned about the warning about kickback.

 

[Modifiedmark]

Well the vanguard is better in that regard, but not as friendly for filing the rakers later on when needed.

 

[gizmodo]

It turns out that is not the correct rim sprocket for the clutch bell. The bell uses the smaller one, part number 18720.

 

[Modifiedmark]

Well, at least that's the most inexpensive part and should not be hard to find locally.

Like I said without any more info or a picture all I could do was guess. Most 60cc saws probably use a standard.