Just a question on compression testing. I've had my 240 Husky for 8-9 years, run hard (not abused, there's a difference!) and thought I'd do a comp test on it. I know everyone and their dog hates these saws, but except for a few wonky carb issues, it's been super reliable. This saw has always been easy to start in the sense of prime, switch on/choke/3 pulls/burp/choke off/1-2 pulls start/blip off high idle, and go. But...it's always been hard to pull in the sense of pull it like you mean it with effort, or it will kick in your hand or literally pull the saw out to the side. Make sense? Which brings us to this. What kind of comp reading should I be getting after all these years? Probably 30-35 cords low ball guess on it. I always run 40 to 1, never old gas, and tune/maintain often. Anyways, it winds up to 175-180 psi...which doesn't make sense to me, especially for a homeowner saw like this. There is actual wear on the piston when you look through the exhaust port, but that was when the saw was new, and set lean from the dealer. Comp tester wonky? Best and tightest 240 ever thrown together? Can a guy actually screw up a comp test? Any thoughts appreciated.
The actual pressure result is pretty unique to the saw engine and it's design. A little saw is quite capable of pumping up a compression tester to 200 psi and beyond. There's a margin of error for compression testers and methods as well. Some people pull it over until the needle stops moving (this is the way), some maybe 3-4 pulls. A longer hose on the tester will take more pulls to get to peak pressure. The strength of the spring in the Schrader valve on your tester will affect the peak result (although that should be pretty negligible). The amount and viscosity of oil on the cylinder walls and ring lands will affect the result. Throttle postion, carburetor throat/venturi size, your altitude ..... Maybe your attitude too. If it runs good, starts without extreme methods, accelerates well and makes good power - doubtful you have a compression related issue! A guy can certainly bork a comp test, but not usually in the direction of better results, unless deliberately adding oil to the cylinder.
Thanks for the input (I've seen your posts on another site, so I know you're not a yahoo) I was pretty certain a guy couldn't screw up a comp test, but you never know lol. I think what more surprised me, was the fact that there is indeed wear on the piston. Then I see a lot lower numbers reading online when people mention compression, so I thought it had to be wonky. I was planning on possibly selling it locally, and wanted to have a honest idea of how it was before it went to someone else.
How high is the quality of your compression gauge? Another words, do you trust that number as accurate?
Not really sure, just borrowed it from dad. Equis? brand Thing is, even if it's somewhat tired, the compression must be alright. Another thing that confuses me is the pull rope drop test. Pause, blub blub, pause, blub blub. It won't hang in the air forever but maybe it's the weight against such a small motor. You can't really drop start it though, it'll whip up or to the side, and you can't one hand the throttle and pull it over (flooded situation), or you'll get a bar in the forehead.
speaking of oil. Just switched to 40/1 mix of red armor. My 462 seems much harder to pull over in cold weather. Sorta like my old wood splitter in the cold. Do people notice this difference much? Should I be noticing a difference?
That makes it harder to convince yourself you need a new toy. Better get rid of that video and pretend it never happened.
It runs great and doesn't owe you a dime. It's heated your home for all these years. Sounds like you take care of it. Who cares what the compression is, that saw has been a home run for you.
A few 1/8th inch "speed holes" drilled in the cylinder walls should fix that problem. More like a carb kit and put a few more miles on her I guess.
Carbon buildup in the combustion chamber and on top of the piston could raise the compression, especially if it’s getting worse slowly over time
Red armor is pretty thck when it gets cold. Those same characteristics are what makes it a really good oil. Amsoil Dominator and Saber are a little bit thinner. You could use those at least for the winter months to help out your cold starting
Thanks for the info. Think I’ll just bring the saws right in the house at night and let them get comfy LOL
That's a good question. Have a few things on the go and company is coming over, but I'll give er a test tonight or tomorrow.
Anything is possible I suppose. Are there any factors that would lead to more carbon buildup when it comes to saws?
I just gave it 2 tests, #1 showing 125-126 psi, and #2 showing just a touch higher half way between 125-130 psi. I thought it would read higher tbh. My father gifted me this saw, it must have been a used or used return at the local saw shop. It starts and runs fine as well.
