vnhill1981
ArboristSite Lurker
I am a new new member here and just wanted to say Thank You to everyone on this thread. Sorry for the long post but here it goes:
I have never owned a chainsaw before. I was in search of one and stopped by a local pawn shop who had a Stihl 025 listed for $200. It did not have a pull cord on it and looked to be "well used". After negotiating with the employee for a bit, we agreed on $75 with the option of returning if the it did not function after I replaced the pull cord. Anyways, got the saw home and it started right up after replacing the cord and seemed to run OK. I bought a compression tester and it read about 120 PSI. I started researching the internet and found this site. I discovered it should probably be somewhere around 150 PSI. Again using this site (as well as Youtube) I completely disassembled the saw. I soaked the cylinder, crankshaft/piston assembly, as well as other metal parts in pine sol for several hours (this will eat the carbon/grime off). The cylinder/piston looked to be in good shape. Because of my ignorance I broke one of the piston rings trying to get them off. once everything was apart, I made a list of replacement parts I needed. These included:
-Piston Rings (I used Caber rings)
-Crank Pan (for those that are wondering, it is a different metal than Cylinder and the pine sol etched the crap out of it)
-Fuel Line w/filter
-Carburetor Gasket
-Air filter
-New Chain
-Tools: Piston Ring Tool
I got all the parts in and assembled the saw. I did a compression test and it read 105 PSI, but the saw seemed to be running/idling good (granted I did not put it under a load). Again I completely tore down the chainsaw checking everything to make sure it was right and put it all back together. I tested it again and only got 110 PSI. I ran it for a little bit and then let it cool down. Once cool, I did one last compression test. I noticed while doing it that the needle kept bouncing and bleeding off. At this point I was able to go by a buddy's house that worked on small engines for over 20 years. I explained to him what was going on and he said that he was unable to get to his compression tester, but the only way to get a true test is to put it under a load and see how it worked. It just so happened he had about an 8-10" diameter oak tree that he needed to cut down. He cranked the saw and went to work. His first diagonal cut started off like a knife through butter, but then the engine started to bog down. He then proceeded to cut the tree up into firewood size logs. During these cuts the chainsaw again ran like a hot knife through butter.
After he was through I asked him about the engine bogging down. He told me that he purposely put excessive force against to see how it would run. He looked at me and said the chainsaw ran great. I asked him about the PSI. He said I most likely had a bad compression tester because the chainsaw is doing everything it should and doing it well. I told him I wish I would've known that so I didn't have to take it apart again a second time. However, on the plus side I can completely take the chainsaw apart and put it back together in about an hour or just a hair under. I explained to him that I was just gonna use the saw for light cutting, say a few oak saplings (5-11" diameter) here and there during hunting season. After hearing this he told me that for my use, as long as I as keep up with the maintenance on the saw it should last me a lifetime. Not bad for $125 in my book. Anyways again I just wanted to say Thank You for the info I gathered from this site specifically, even though y'all did not know you were helping me. Here are some before and after pics:
I have never owned a chainsaw before. I was in search of one and stopped by a local pawn shop who had a Stihl 025 listed for $200. It did not have a pull cord on it and looked to be "well used". After negotiating with the employee for a bit, we agreed on $75 with the option of returning if the it did not function after I replaced the pull cord. Anyways, got the saw home and it started right up after replacing the cord and seemed to run OK. I bought a compression tester and it read about 120 PSI. I started researching the internet and found this site. I discovered it should probably be somewhere around 150 PSI. Again using this site (as well as Youtube) I completely disassembled the saw. I soaked the cylinder, crankshaft/piston assembly, as well as other metal parts in pine sol for several hours (this will eat the carbon/grime off). The cylinder/piston looked to be in good shape. Because of my ignorance I broke one of the piston rings trying to get them off. once everything was apart, I made a list of replacement parts I needed. These included:
-Piston Rings (I used Caber rings)
-Crank Pan (for those that are wondering, it is a different metal than Cylinder and the pine sol etched the crap out of it)
-Fuel Line w/filter
-Carburetor Gasket
-Air filter
-New Chain
-Tools: Piston Ring Tool
I got all the parts in and assembled the saw. I did a compression test and it read 105 PSI, but the saw seemed to be running/idling good (granted I did not put it under a load). Again I completely tore down the chainsaw checking everything to make sure it was right and put it all back together. I tested it again and only got 110 PSI. I ran it for a little bit and then let it cool down. Once cool, I did one last compression test. I noticed while doing it that the needle kept bouncing and bleeding off. At this point I was able to go by a buddy's house that worked on small engines for over 20 years. I explained to him what was going on and he said that he was unable to get to his compression tester, but the only way to get a true test is to put it under a load and see how it worked. It just so happened he had about an 8-10" diameter oak tree that he needed to cut down. He cranked the saw and went to work. His first diagonal cut started off like a knife through butter, but then the engine started to bog down. He then proceeded to cut the tree up into firewood size logs. During these cuts the chainsaw again ran like a hot knife through butter.
After he was through I asked him about the engine bogging down. He told me that he purposely put excessive force against to see how it would run. He looked at me and said the chainsaw ran great. I asked him about the PSI. He said I most likely had a bad compression tester because the chainsaw is doing everything it should and doing it well. I told him I wish I would've known that so I didn't have to take it apart again a second time. However, on the plus side I can completely take the chainsaw apart and put it back together in about an hour or just a hair under. I explained to him that I was just gonna use the saw for light cutting, say a few oak saplings (5-11" diameter) here and there during hunting season. After hearing this he told me that for my use, as long as I as keep up with the maintenance on the saw it should last me a lifetime. Not bad for $125 in my book. Anyways again I just wanted to say Thank You for the info I gathered from this site specifically, even though y'all did not know you were helping me. Here are some before and after pics:
