Will a compression gauge read the same if you spin the saw backwards ?
Here is a question for you
- Thread starter ZeroJunk
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I would think, so a dirt bike can run backwards .
Nah, just spinning a concrete saw from the flywheel side and trying not to spin the nut off.
I think so. I've seen a 2-stroke dirt bike run backwards.........
Wolfie beat me to it!
Growing up a kid stalled one going up a steep hillclimb, it rolled backwards, and started
Wolfie beat me to it!
Growing up a kid stalled one going up a steep hillclimb, it rolled backwards, and started
Don't have the plug wire connected and/or have the kill switch on.
I had one start in my shop backing it out the door the Kickstarter caught on an airline started it and IDK how the hell it got in reverse but it took off backwards out of the shop into the driveway.
Comp gauge in the plug hole. Piston looks fine from the muffler, but no compression to amount to anything.
SteveSr
Addicted to ArboristSite
Piston have a hole in it?
Don't think so, it shows maybe 80 pounds. I think the intake said of the piston and cylinder is scarred, not scored.
The air filter had never been cleaned. Had to drill one of the filter cover screws out. Filter was a solid hunk of wet mortar.
I may pull the top off if I get bored.
So what saw is it?
Dump little bit of oil into the spark plug hole and then compare compression. If it goes up by about 20 psi the rings are bad or stuck.
You can sometimes see a stuck ring looking carefully through the muffler port.
Yes they should check the same either direction of rotation , but a Wolfe said the flywheel nut will usually come off
What model saw is it???????????
You can sometimes see a stuck ring looking carefully through the muffler port.
Yes they should check the same either direction of rotation , but a Wolfe said the flywheel nut will usually come off
What model saw is it???????????
I quite often spin saws backwards to check compression due to the flywheel nut being RH threads. My experience is the compression is the same forwards or backwards on a 2 stroke (reed valve or piston ported). I have not tried this on a rotary valve engine. I suppose the timing of the intake on those might have some effect on compression if air cannot enter the crankcase at the right time.
Mark
Mark
daniel cosgrove
ArboristSite Lurker
may be stuck rings , had saws run with **** oil and fouled the rings up that much they were stuck and not seating against the bore . soon as i clean all the burnt oil out of the ring grooves the compression was good again hope this helps
LOL, I figured that out eventually.
I was using a regular 3/8 ratchet to get the thing unlocked on the flywheel side. You could spin it either way with that.
But, when you put the air ratchet on it spun it loose.
A lot of snowmobiles run backwards to go backwards, that's their reverse lol.
If you had to pour oil in it to get it to turn over it's toast, why waste time doing a compression test just tear it down.
If you had to pour oil in it to get it to turn over it's toast, why waste time doing a compression test just tear it down.
Because the exhaust side of the piston still has the tooling marks and looks like new.
Two strokes can run backwards but the ignition timing will be off. The Mercury dockbusters, as they were called did not have a shifting foot, instead, the motor would stop and start up in reverse. If it didn't start in reverse, you busted the dock.
