Hi my grandpa has a stihl 020t that he has been cutting limbs with for over 20 years. Recently he was cutting on his log pile 1 log rolled down from the top of his pyle and luckily he was able to get out of the way fast enough but the saw was not. When it was struck by the log it instantly stopped running. He brought it to me hoping it would be an easy fix. I'm pretty good with small engines but this thing has got me stumped. I can get it running but it won't stay running sometimes it will start first pull other times it won't evan start weather you are review it up or idling it will just die.sometimes it will idle and rev up for about 30 seconds and then die. It's like the kill switch has shorting but I can't determine if it is. Here is what I have done in this order. Replaced both main seals. Cleaned the carb with a fine tooth comb and ultrasonic cleaned I have done this twice. Replaced impulse line. fuel line looks fine. replaced coil with a new one but have not replaced coil wire ( high voltage wire) it seems to be getting gas and also has spark. For some reason when I put a ohm meter across the spade connecter on the coil and the case it is closed. My other saws are open that's why I am confused any help on this night mare would be awsome. Also I have presure tested the crank case under postie and negative pressure. And it held 25 psi on both for 1 minute.
Stihl problems
- Thread starter Lady bug
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Compression test? Bent or pinched bar and along that line bent chain causing excessive drag- as you didn't say if the test runs were with complete assembly or just the power head. it is also possible for a switch to be bad internally -intermittently.
Does this have a condenser on/for the coil- could also be suspect.
Does this have a condenser on/for the coil- could also be suspect.
The test runs are just power head. the compression reads 60 but I don't know how that could be seeing how it was cutting fine before it was struck by the log. May have cracked the jug? I took apart cylinder and inspected bore and piston all looked good. It has just a coil mounted above the flywheel it does this with the switch disconnected. Thanks for reply and your help!
Torn intake boot from log clobbering?
My compression tester has to deep of a throw on the adapter. Piston touches it. I need to get a shorter adapter to properly test the compression. That still leaves me confused as why the log did it in?
In addition to jug cracked - base gasket leak - don't really know until proper compression check even then won't always show up . Sure sounds like a you are missing a tiny nick in the lead to the switch somewhere that it is contacting the case intermittently. Bad Plug?
One of my Dolmars got knocked around pretty good but ran fine until you went to shut it down then it would start revving out of control until ya jammed into a log. That was a base gasket leak- only got caught by blind luck- found out later that were some issues on that particular jug case series base gaskets as the replacement was totally different. ( 6400 and 7900)
One of my Dolmars got knocked around pretty good but ran fine until you went to shut it down then it would start revving out of control until ya jammed into a log. That was a base gasket leak- only got caught by blind luck- found out later that were some issues on that particular jug case series base gaskets as the replacement was totally different. ( 6400 and 7900)
OK I will get a proper compression check. Evan with the kill switch not hooked up it acts this eratic. Somtimes starts on first pull will idle rev up twice then die. Other times won't evan start. Weather it's up to running temp or not. I put a new plug in and ensured it was working properly by running it in my other saw with no issues. Lost in this one could the high voltage plug wire be the issue (grounding out) I checked with ohm meter and it seems to be fine.
Start rev then die- sounds more like a carb issue on that portion like a pin leak in diaphram or blocked passages- got to love ethanol. got a string trimmer here Homelight similar issues I know its the carb and I know its a zama carb but I will dxxxxx if I can find a model # on it and it is a royal pia to pull off.
I work on dozens of these saws if you want to PM me I will talk to you on the phone it saves time.
Right. Your gauge must be off .
tomdcoker
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I have 2 020 saws. One was running until recently and was as dependable as you could want it to be. Then I started having trouble with it and have not got around to checking it. I really like my, but I was told by a man that has been in the small engine business for 40 years that the most common problem with the 020 is the carb. and I have found that to be true. The 020 is an old saw, but a good saw. Good luck in getting it repaired. Tom
