Chainsaw Repair

How To Basics - Carb Fixes + Mods - IPL and Service Manuals => How To Basics and Fixes => Topic started by: KilliansRedLeo on January 02, 2014, 06:53:47 pm

Title: Measuring Squish
Post by: KilliansRedLeo on January 02, 2014, 06:53:47 pm
I am doing a post on the modification of a 261 Husqvarna. I want the reader to measure squish prior to taking the saw apart. If you measure squish without cleaning any accumulated carbon off the piston you will get a less that accurate measurement of the squish. Normally this is done with new/clean pistons, so I know it will not be 100% accurate, I just need a ballpark measurement. Should I just forget this stop or can I add/subtract some nominal factor from the squish measurement to partially account for the carbon? What is your experience?
Title: Re: Measuring Squish
Post by: mdavlee . on January 02, 2014, 07:34:24 pm
 I don't usually bother with carbon removal if there's some there. It's usually not thicker than .002-.003" at the most.
Title: Re: Measuring Squish
Post by: KilliansRedLeo on January 02, 2014, 07:43:41 pm
I don't usually bother with carbon removal if there's some there. It's usually not thicker than .002-.003" at the most.

Cooooooool, just what I needed to know. So if they measure 0.035 squish they can add 0.002 to 0.003 to that and get 0.037 to 0.038!


Title: Re: Measuring Squish
Post by: 660magnum on January 02, 2014, 07:47:28 pm
I always considered that the soft carbon got mashed down and some of it got embedded into the solder etc. That it wasn't enough to bother with and when you run the engine, the carbon will return.
Title: Re: Measuring Squish
Post by: Al Smith on January 02, 2014, 07:51:46 pm
I lift the cylinder ,remove the rings and clean everything up first .Then half the time miss cutting and have to fumble around and make a different gasket .Not a big deal if you don't cut enough .You can always recut it .Kinda tough to put it back on though if you cut too much .