Chainsaw problem
- Thread starter rube2112
- Start date
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Rftreeman
Addicted to ArboristSite
same hereopcorn:
me too........
Muffler Off
I just inspected the muffler side of the piston.....No visible scoring or anything. There is a burn ring above the piston ring but that is normal above the ring. No visible scoring on the opposite cylinder wall either. I don't know what is going on.........Robb
I just inspected the muffler side of the piston.....No visible scoring or anything. There is a burn ring above the piston ring but that is normal above the ring. No visible scoring on the opposite cylinder wall either. I don't know what is going on.........Robb
Lakeside53
Stihl Wrenching
So.. what's your compression? Make sure your tester has a schrader valve AT the screw in tip.
blackoak
Addicted to ArboristSite
I think the 455 was old Saps choice of weapon for milling wasn't it??? And Sap was never wrong.:hmm3grin2orange:
I don't think I have a compression tester anymore.....I can stop the compression with my thumb......not very scientific though......Robb
blackoak
Addicted to ArboristSite
Do you have a schrader valve on your thumb??
nope.....sorry......I lost it!!
blackoak
Addicted to ArboristSite
Then your probably getting a false reading.
Picture 1. This picture is decieving....there is NO scoring.......only dark coloration.
Picture 2. This is the bottom portion of the piston as the crankshaft pushes it to its topmost position.....completely pristine......unmarked.
Picture 3. Cylinder wall in focus......no marks......only a little dirt and oil. Robb
willsaw4beer
Addicted to ArboristSite
Hard to tell from the photos, but it looks okay.You could always try the highly scientific drop test as a measure of compression.
what exactly am I supposed to drop?
God willing you'll get away with a set of rings. Next time out mix your fuel at 20:1. Use the best two stroke oil you can find and pay close attention to the engine temp. Make a cut and then stop and cool down.
Attached is a picture of a Stratocharged engine so you can see whats going on. They call the scavenging cycle air 'lead' air, as its ahead of the fuel/oil charge. There should be two small reed valves on the sides of the cylinder that allow this incoming air charge to clear the exhaust.
Attached is a picture of a Stratocharged engine so you can see whats going on. They call the scavenging cycle air 'lead' air, as its ahead of the fuel/oil charge. There should be two small reed valves on the sides of the cylinder that allow this incoming air charge to clear the exhaust.
Justsaws
Addicted to ArboristSite
Do the rings move in and out if you push on them?
There seems to be a lot of build up present in the photos.
There seems to be a lot of build up present in the photos.
willsaw4beer
Addicted to ArboristSite
Hold the pullcord handle and drop the saw, it shouldn't just drop straight down it should catch a few times on the way down...
No it doesn't drop straight down.....it does catch.....Now since I've looked inside the saw I'm wondering if its possible that a few drops of water are in the carb or something........none of this makes any sense. And since alot of you are talking about how lean the saw runs......how much richer should I adjust it to assuming that I can get it running? Do I need to remove the factory carb adjustment stops?.....Robb
willsaw4beer
Addicted to ArboristSite
Thanks............Robb
Justsaws
Addicted to ArboristSite
Is the decompression valve closing? Pull it shut and it should have a firm snap to it.
Yes it is closing......this thing just won't start........has to be compression......It sure does act like it has enough to start but it just doesn't......spark plug gets wet........spark plug sparks..........has to be damage.....Robb
