Checking Chain Brake? Also, new logger questions

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Thanks, fellas.

Aside from the issue of how exhausting that kind of work must be, I bet it's a lot of fun to work in the woods all day every day. I grew up hunting and fishing and love being out there, although what with all the rain you guys deal with in the PNW, maybe it ain't so peachy sometimes...THERE WILL BE MUD...

What size CC saw are most of you fallers using out there? Is there a "most common saw size"?

70-90cc is common at least around here.

most of the hand cut timber is oversize now anyway, so 90cc saws are becoming the norm (over 36" on the stump)

Don't move here...
 
"experienced" guys thought poulan was heavy for power. 5200's mighta changed their minds. same saw, bigger bore.
think most of what was out there in 70ish cc then were kinda heavy. found out later 77 & 82 cc homelites were healthy.
gov issue saws. we just ran em.
 
Just got my aftermarket 660 from thechainsawguy on ebay and I gotta say it looks great! I'm guessing maybe it was largely from Farmer Tec parts, with Meteor piston and jug, Caber rings, Olean wrist pin bearing, Taiwanese crank and some OEM parts like circlips, also it has an Oregon clutch drum and sprocket and (I think) a dual-port muffler. Fired right up and she pulls good. Decomp button is plugged, but that has only given me trouble on my 361 so I don't care.

Just thought I'd let you guys know if you were considering buying from him (no connection to me)...
 
Thanks for the heads-up. Here's hoping I have a better outcome! (His ebay rating...or at least the one they show on the "for sale" page...was 100%. Maybe that's just from the past year or something. There seem to be a few different people going by the handle "thechainsawguy" on ebay and youtube...I think one of the youtube guys who goes by that name retired last year...it's hard to piece together. The guy I bought from is in Black Creek, BC.)

I was thinking of having my local saw guy look over the 660 and maybe do a vacuum and pressure test just so I don't blow the thing up straight out of the gate ... would you guys do this if you were me? I'm not sure I would recognize an air leak from the saw's behavior.

Also, should I re-torque the jug-to-crankcase bolts after 5 or 10 tanks? (That I can do myself.) I thought I saw something about that in one of the manuals...
 
Thanks, guys.

Never needed to retorque cylinder bolts...

Just so I understand, you mean you checked them and they were still at proper torque, or you never checked them? (I found in the owner's manual where they say to retorque after 10-20 hrs.) From what I've read it sounds like maybe the base gasket can shrink in thickness after break-in/cook-in enough to change how far the bolts are stretched/strained, but after you retorque them, supposedly they're good thereafter...?

Just trying to do it by the book here. Don't want to give the saw any excuse to fail.
 
maybe the base gasket can shrink in thickness after break-in/cook-in enough to change how far the bolts are stretched/strained, but after you retorque them, supposedly they're good thereafter...?

This was bugging me WHY? but here's one possible explanation. When the engine heats up, the aluminum cylinder and the aluminum crankcase expand, and the steel screws joining them expand, but not as much. In fact, only about half as much. (Coefficient of linear thermal expansion for aluminum is double that of steel.) What that means is that when the engine heats up, and the aluminum pieces expand about twice as much as the screws holding them together, the gap between the aluminum cylinder and the aluminum crankcase is decreased...which effectively "crushes" the gasket every time the engine heats up.

Eventually, I imagine the gasket doesn't "spring back" (expand fully to its original thickness) on cool-down, which means that the screws won't be as elastically stretched as they were when they were installed. Which means their torque values will decrease, even though they didn't loosen in the sense of rotating counterclockwise. But after enough heat-up/cool-down cycles, the gasket stops getting thinner (it probably gets harder and thinner, but after a point it won't get any thinner), and so when you re-torque after 10-20 hours of run time, you probably don't need to re-torque ever again.

Anyway, that's my theory on what happens and why Stihl says to do it...
 
Thanks for the heads-up. Here's hoping I have a better outcome! (His ebay rating...or at least the one they show on the "for sale" page...was 100%. Maybe that's just from the past year or something. There seem to be a few different people going by the handle "thechainsawguy" on ebay and youtube...I think one of the youtube guys who goes by that name retired last year...it's hard to piece together. The guy I bought from is in Black Creek, BC.)

I was thinking of having my local saw guy look over the 660 and maybe do a vacuum and pressure test just so I don't blow the thing up straight out of the gate ... would you guys do this if you were me? I'm not sure I would recognize an air leak from the saw's behaviour.

Also, should I re-torque the jug-to-crankcase bolts after 5 or 10 tanks? (That I can do myself.) I thought I saw something about that in one of the manuals...
I always re-check everything. It doesn't, mean they will need it but its worth the min it takes. muffler bolts too. Thechainsawguy, DAVE, is active on this site, mainly in the sales thread. You can read his posts and threads. He has a long-standing rep. and many happy customers. first time i ever heard anything negative. As for the Chinese parts..... its hit and miss. lots of big suppliers deal in them too.
 
Thanks, guys.



Just so I understand, you mean you checked them and they were still at proper torque, or you never checked them? (I found in the owner's manual where they say to retorque after 10-20 hrs.) From what I've read it sounds like maybe the base gasket can shrink in thickness after break-in/cook-in enough to change how far the bolts are stretched/strained, but after you retorque them, supposedly they're good thereafter...?

Just trying to do it by the book here. Don't want to give the saw any excuse to fail.
Some I've checked, others run em till they die, rebuild+repeat.

Only had one saw where the cylinder gasket was the culprit for it dying, and I inherited it that way, one bolt was out and wedged into a cooling fin...

Far as proper torque? go until the wrench flexes... hasn't failed me yet. (note this only works on Allen type wrenches and T handle Torqs wrenches, if you can flex a 7/8 box end wrench without breaking a bolt...)

Yer also sorta half right with the heating cooling aspect, but its mostly a matter of the bolt getting its stretches in, the gaskets are metal, and not likely to move much, but the bolts have multiple planes on which they can move, both from vibration and heat stresses.

To be clear, I've never personally blown up a saw (I mostly run em over), I've loaned em out and had them get roached (hot saws and dull chains are a bad combo), and I get a bunch of dead saws and make them go again from time to time... I get bored, and antsy, cheaper then a drug addiction and legal too.

If yer saw is suckin air where its not supposed to it will be a ***** to tune, and continually get worse until it leans out far enough and burns up. A competent shop with a vacuum tester can check em in about 10 minutes, a used saw will generally have one or the other crank seals go bad, also an easy fix with the right tools...

A new saw if its leaking could be anywhere, and likely expensive.
 
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