Stihl 500i

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Apparently I had a stuck decomp.... It was causing the saw not to start. In the process of troubleshooting I also pulled the plug (little guy) to check for what sounded like lean running to me (it didn't show any signs of that and it does run a bit higher 13000) and wiggled some wires. Since then the saw fires on one pull, I can let it sit for a while and it now still fires right up. I've now run about 12 tanks thru it and am pretty pleased with it. Fun with a 25 on it... feel like even more of ninja now with the awesome throttle response :) Time will tell....
Mine has the stiffest decomp I have ever encountered. I cannot get a sufficient grip on it to close it manually. Probably why I too have encountered times that require multiple pulls to restart.

Ron
 
Mine has the stiffest decomp I have ever encountered. I cannot get a sufficient grip on it to close it manually. Probably why I too have encountered times that require multiple pulls to restart.

Ron
Glad to hear mine is not the only one. My issue has been more with cold starts than restarts. I'm used to decomps that pop with just a vigorous pull - the 500i often doesn't pop even when the saw fires several times (and then dies due, I'm guessing, to low compression).
 
Buckin’ just got one from a friend. I think he liked it, but he ran his mac’s almost as much in that same video, needless to say I don’t think he’s a convert to Stihl or the 500i just yet :laugh: Joking aside it was a fun video, check it out.
 
I purchased a 500i this week and have only used it a few times. I've experienced some hot starts where the saw will fire and then stall and in each of these cases, it was because the de-compression valve didn't pop out.
 
The saw will gain compression as the rings seat, and you guys need to pull harder/faster, if you're not used to an 80cc saw with a good bit of compression you will have issues, that's likely the main problem here IMHO.
My 73 year old shoulders may no longer be able to spin the engine fast enough, but... The saw is firing and runs very briefly before dying with the decomp still depressed. After I pry it up (with a scrench because my gloved fingers can't get a good enough grip), the saw starts. A saw that runs, even briefly, without popping the decomp closed is new to me. I have several saws that close the decomp with every pull regardless of whether the saw fires or not.
I hope you're right about the issue going away as the saw gets more hours, but I'd have thought 15-20 tanks would be enough.
 
My 73 year old shoulders may no longer be able to spin the engine fast enough, but... The saw is firing and runs very briefly before dying with the decomp still depressed. After I pry it up (with a scrench because my gloved fingers can't get a good enough grip), the saw starts. A saw that runs, even briefly, without popping the decomp closed is new to me. I have several saws that close the decomp with every pull regardless of whether the saw fires or not.
I hope you're right about the issue going away as the saw gets more hours, but I'd have thought 15-20 tanks would be enough.
I would try a new decomp in that case or just not use it, I don't 95% of the time, especially with a warm saw.
 
The saw will gain compression as the rings seat, and you guys need to pull harder/faster, if you're not used to an 80cc saw with a good bit of compression you will have issues, that's likely the main problem here IMHO.
Our mileage must differ. I run more saws over 80cc than under. The decomp on my 500i is just plain stiff. Push it in and you can't grip it well enough to pull it out with your fingers. Besides I want the saw to close the decomp once it fires. IME if you want to hurt yourself, fool with a high compression or advanced timing 100+ cc saw with a decomp that closes early. It will rip the starter handle out of your hand or hurt your shoulder or both. Ron
 
Our mileage must differ. I run more saws over 80cc than under. The decomp on my 500i is just plain stiff. Push it in and you can't grip it well enough to pull it out with your fingers. Besides I want the saw to close the decomp once it fires. IME if you want to hurt yourself, fool with a high compression or advanced timing 100+ cc saw with a decomp that closes early. It will rip the starter handle out of your hand or hurt your shoulder or both. Ron
Yes that will happen, and in the cold you loose use of that hand for a bit. Stihl has in the past had issues with the decomps being too weak, maybe too stiff now, you could always try a Husky decomp, those always seem to work, definitely better than the Stihl decomps.
 
The saw will gain compression as the rings seat, and you guys need to pull harder/faster, if you're not used to an 80cc saw with a good bit of compression you will have issues, that's likely the main problem here IMHO.
I want an electric starter. Keep it off saw like the Formula 1 cars to save weight. Maybe a battery electric drill attachment. That way I would be OSHA compliant by not drop starting all my saws.
 
My 73 year old shoulders may no longer be able to spin the engine fast enough, but... The saw is firing and runs very briefly before dying with the decomp still depressed. After I pry it up (with a scrench because my gloved fingers can't get a good enough grip), the saw starts. A saw that runs, even briefly, without popping the decomp closed is new to me. I have several saws that close the decomp with every pull regardless of whether the saw fires or not.
I hope you're right about the issue going away as the saw gets more hours, but I'd have thought 15-20 tanks would be enough.
Bad decomp valve. You can get a new valve like Andy says, or if you do not use it just plug it with a bolt. Also with a sticky decomp you are apt to run lean, and that can ruin an engine.
 
Yes that will happen, and in the cold you loose use of that hand for a bit. Stihl has in the past had issues with the decomps being too weak, maybe too stiff now, you could always try a Husky decomp, those always seem to work, definitely better than the Stihl decomps.
Bad decomp valve. You can get a new valve like Andy says, or if you do not use it just plug it with a bolt. Also with a sticky decomp you are apt to run lean, and that can ruin an engine.

My previous Stihls were/are mid sized - 036, 361 and 362. I am not aware of any issue with their decomp. I do know my larger old MACs don’t seem to care much, they still crank and run with an open or even missing decomp which is why I have never thought to attribute the 500i issues to an open decomp. I think I will remove it and see if it needs a little fitment work. Will also give my other Stihls a look see.
Thanks, Ron
 
Buckin’ just got one from a friend. I think he liked it, but he ran his mac’s almost as much in that same video, needless to say I don’t think he’s a convert to Stihl or the 500i just yet :laugh: Joking aside it was a fun video, check it out.
Play that video back again - he was grinning when the rings started to bed in and the saw really started to sing! I reckon he does really like the saw but he's a husky man to his core for work saws.
 
Play that video back again - he was grinning when the rings started to bed in and the saw really started to sing! I reckon he does really like the saw but he's a husky man to his core for work saws.
Ah I was only messing around, I agree I think he liked it.

I must admit, I couldn’t hear any change in the saw when he was doing those cuts, could you? I’ll listen again and try and hear it, but tried a couple of times and couldn’t tell.
 

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