Stihl MS 211/C with low compression issue

[John Rainford]

It cuts straight and the chain is sharp.   I don't have the easy start' on my saw so you can hold it at waist height and test the compression by holding the starter rope and letting it drop. It drops a little way, then holds for a few seconds, then drops a little again and then holds for a few seconds and then drops to the ground.

[billpierce]

It cuts straight and the chain is sharp.   I don't have the easy start' on my saw so you can hold it at waist height and test the compression by holding the starter rope and letting it drop. It drops a little way, then holds for a few seconds, then drops a little again and then holds for a few seconds and then drops to the ground.

Dress the rails on your bar. And measure the gap between them and check its not over worn. Also check its the correct gauge chain for the bar

[Stubby]

2 hours ago, billpierce said:

2 hours ago, John Rainford said:

It cuts straight and the chain is sharp.   I don't have the easy start' on my saw so you can hold it at waist height and test the compression by holding the starter rope and letting it drop. It drops a little way, then holds for a few seconds, then drops a little again and then holds for a few seconds and then drops to the ground.

Dress the rails on your bar. And measure the gap between them and check its not over worn. Also check its the correct gauge chain for the bar

He says it cuts strait ....

[billpierce]

He says it cuts strait ....

Had saws which appear good and sharp cut straight and cut well then appear to stop almost like they have hit metal....rails were worn and chain just flopped over a bit from time to time in the cut and stopped cutting.

[spudulike]

I have seen the same, usually when the rail slot is excessive but the fella said it was lacking power and normally a worn bar will allow the engine to rev like bonkers but cut near to zero chip.

 

[bmp01]

On 25/11/2019 at 17:51, John Rainford said:

It cuts straight and the chain is sharp.   I don't have the easy start' on my saw so you can hold it at waist height and test the compression by holding the starter rope and letting it drop. It drops a little way, then holds for a few seconds, then drops a little again and then holds for a few seconds and then drops to the ground.

 Compression seems ok then. I just went and checked my 211, exactly as per your description, takes nearly 30 seconds to completely unwind the starter cord. Personally I'd still check the piston.

If it's the bar or chain as suggested how new / old are they ? Is the chain overly aggressive, rakers set too deep ? Is it oiling the chain, bar getting hot ? Has someone changed the sprocket to 7 tooth ? 

 

Simple engine things,  swap spark plug, air filter clean, checking fuel lines, fuel tank breather, carburettor tune up.

Beyond that its anyone's guess - there's no substitute to seeing the misbehaving saw first hand.

 

bmp01