MS170 cuts slowly, leaves burn marks

[isv]

I'm thinking about buying a used MS170 (12" bar) from a neighbor. He let me borrow it today to try it out and when he dropped it off he said it was 'all ready to go'.

I'm new to chainsaws (just 1/2 day course last winter) and it was obvious to me something was 'wrong' with the saw. It doesn't cut easily and the chain easily stalls. I only tried 4 cuts (logs about 4" diameter) and each cut was left with some heavy scorching. The bar was also discolored at the top - like it was way too hot. The saw was also emitting a lot of smoke. I was cutting at full throttle and trying not to put any pressure on the cut but it was obvious the saw was not getting through easily.

I looked at the chain and it seemed sharp but may have been too tight - I've not got any experience to go by, but although I could move the chain by hand I had to pull hard.

If it is an easy thing to fix I might still go for it (it is cheap, light and easy to handle) - but would obviously not want a saw with a major problem. Can anyone suggest an obvious cause of the problem?

Alan.

(and yes, before anyone asks...I did have the chain brake disengaged!)

 

[SawTroll]

The 170 never was a very good saw, I would just stay away from one with problems.......

...but from your description, it seem like the chain is too tight, and maybe there is an oiler issue also + lots of dirt??????

Take the bar and chain off, and clean them (+ the sprocket area), then adjust to "no sag, no drag" when you put them on.

 

[jack-the-ripper]

Sounds like the chain was overtightened. Did you notice if the oiler was working properly? If your neighbor tightened the chain while it was still hot, it will get tighter as it cools putting stress on the crank. Where are you at Lakeside?

 

[B_Turner]

Heat generally means dull chains, or improper lubrication. With too tight a chain maybe thrown in.

If it cuts 4 inches badly with the motor running, I say the chain has sharpness issues. I assume it is on frontwards...

 

[windthrown]

Heat generally means dull chains, or improper lubrication. With too tight a chain maybe thrown in.

If it cuts 4 inches badly with the motor running, I say the chain has sharpness issues. I assume it is on frontwards...

Ohhh, a backward chain!?! Not too likely, but be sure to check that the chain is set with the blades facing away from the engine on top of the bar, and toward the engine on the bottom. I have to agree that chances are that it has a dull chain. Dull chains will smoke and burn from friction in wood, rather than cut, even with a high power saw (your description here). A 170 is not all that powerful, and with a slightly dull chain it is going to bog down in any real wood. The chain should be tight but you should be able to snap it off the bar a bit and move it back and forth with your hands. Make sure that the chain brake is off and the saw is off before you try to move the chain back and forth and check for play (pull the chain brake back toward you to unset it).

Maybe he needs a woods mod for his 170???

 

[dtnodya]

I bet the chain was on backwards.

 

[Ianab]

Also 'seems sharp' and 'Really sharp' are two different things. The chain should be razor sharp (like it will slice your finger if you aren't carefull handling it)

Like the others have suggested, take the bar off and clean it out. Scrape the crud out of the groove and clean out the oiler hole. Then reassemble and check the tension, the chain should turn freely by hand but be snug on the bar, you should just be able to lift it up and see the tangs under the cutters. Then sharpen it. It may even be sharpened wrong, who knows?

No reason it shouldn't cut OK if the engine and oiler are working right, but it sounds about like my Stihl after a teeneager used it to saw dirt :bang:

Cheers

Ian