Tightening flywheel nut on Stihl ms170

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I would have no problem tightening it by feel, if i locked the piston.

Without piston locked have very little feel.

No convinient place to slot scredriver to lock flywheel unfortunately.
 
I would have no problem tightening it by feel, if i locked the piston.

Without piston locked have very little feel.

No convinient place to slot scredriver to lock flywheel unfortunately.

A length of soft rope inserted into the spark plug hole works great as a piston stop. Just be sure the piston is just above the ex port so you don't jam the rope in a port.

DSC_0025.JPG
 
I was thinking of using nylon or cotton type rope 5-6mm (approx 1/4 inch) double fold, so no end of the rope is going into cylinder, to reduce the chance of fraying residue. Inserting it double folded side rather than loose end side. Also that way it is easier to inspect the rope when taken out if it is intact.

If i ever get around to doing it, or anytime soon.
 
Anyone remember the bent con rod syndrome on the small saws with the stamped out con rods. I believe Brad Snelling was the first to post about it in a thread on here. A few of the engineer types all piled on that thread and it was determined the best piston stop was the one sold by Stihl made of a white plastic material. Thall added that the plastic stop was designed especially for the 170 sized saws and others with that same style con rod.
 
I use a piece of 3/8 nylon, less chance of getting in port
I was thinking of using nylon or cotton type rope 5-6mm (approx 1/4 inch) double fold, so no end of the rope is going into cylinder, to reduce the chance of fraying residue. Inserting it double folded side rather than loose end side. Also that way it is easier to inspect the rope when taken out if it is intact.

If i ever get around to doing it, or anytime soon.

The rope in the picture is a soft braided nylon, it feeds in the plug hole easy, not sure of dia.?

When you cut nylon rope, fuse the end strands by burning it a bit, and cooling.
 
Anyone remember the bent con rod syndrome on the small saws with the stamped out con rods. I believe Brad Snelling was the first to post about it in a thread on here. A few of the engineer types all piled on that thread and it was determined the best piston stop was the one sold by Stihl made of a white plastic material. Thall added that the plastic stop was designed especially for the 170 sized saws and others with that same style con rod.

I missed Brad's thread and didn't know about the 170 cranks/stamped rods. Will see if I can find it.

Would those 170s get hurt using rope as a piston stop? Soft rope spreads the force out over a good portion of the piston dome.
 

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