aztoad
ArboristSite Member
...Also, I haven't pulled the limiter caps yet as folks were suggesting to hold off...
Not sure what else to try at this point...
Not sure what else to try at this point...
Dead 290?? Any help out there - please!
- Thread starter aztoad
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2000ssm6
Stihl User
I know this is bad advice and should not be used. Clean the plug and dry the cylinder out good, take the air filter off, hold the throttle wide open, shoot a short burst of carb cleaner into the throat. Try to start it on "start" no choke. This is bad because there is no lube in carb cleaner and could score your cylinder if used over and over. Don't do this but once. I only say use this method because I can't tell if you are flooding the engine with mix. If it has a fuel problem, carb cleaner will make it start.
Fire away guys......
Fire away guys......
aztoad
ArboristSite Member
I know this is bad advice and should not be used. Clean the plug and dry the cylinder out good, take the air filter off, hold the throttle wide open, shoot a short burst of carb cleaner into the throat. Try to start it on "start" no choke. This is bad because there is no lube in carb cleaner and could score your cylinder if used over and over. Don't do this but once. I only say use this method because I can't tell if you are flooding the engine with mix. If it has a fuel problem, carb cleaner will make it start.
Fire away guys......
After 20 pulls - nada
I pull pretty hard and even ran a multimeter on a few pulls to see what it was reading and it went to overload - over 1300 volts
2000ssm6
Stihl User
On the rented comp. gauge, what was the highest reading? After about 10 pulls it should have peaked......
aztoad
ArboristSite Member
2000ssm6
Stihl User
Dam, no wonder it won't start.:jawdrop: A new broken in saw is around 160psi and a borderline wreck is 120-ish. I don't think it has enough psi to fire...
You need to try another gauge to rule out a bad reading. Make sure it's seated in the engine good.......
aztoad
ArboristSite Member
First I'll try to reseat the gauge - and report if there is a change.
If no change - I'll grab another gauge in the morning. When the plug is inserted - neither my wife nor my 19 yo daughter can pull it safely at all.
Make sure the compression guage your using has a Schrader valve right at the tip where it screws into the cylinder. Guages are pretty cheap at your local automotive parts store.
aztoad
ArboristSite Member
I don't think this one is very high quality but after reseating and tightening a bit more, I still was only able to pull out about 100 psi.
I'll grab a new gauge in the morning when I'm out.
I don't think I've become that weak but this thing is a bear to pull. Can't quite believe it has a compression issue but then again - it isn't working yet either!
2000ssm6
Stihl User
This may be a easier way to pull.....Try sticking your foot(toe end)into the handle and hold the top down with your left arm/hand. If it's that hard to pull it should have good psi.....
aztoad
ArboristSite Member
That is exactly how I normally start it - can only use the drop start when it has been warmed up!
2000ssm6
Stihl User
I always drop start....LOL. You would have a hell of a time starting my 460 or 660, decomp is a must. A Mac CP125 is worse, that sob will rip your arm off.
aztoad
ArboristSite Member
I always drop start....LOL. You would have a hell of a time starting my 460 or 660, decomp is a must. A Mac CP125 is worse, that sob will rip your arm off.
Thinking the issue is the gauge. With the plug in, it still is too hard a pull for the kids.
That still leaves me with the carb / timing...sounds like there really is no timing option so it is back to thecarb and that probably leaves me with the issues of removing the limiter caps....
...unless someone has another thought....
I always drop start....LOL. You would have a hell of a time starting my 460 or 660, decomp is a must. A Mac CP125 is worse, that sob will rip your arm off.
Try pulling a 084 or equivalent without pushing the decomp button
You know nothing definatively until you get a proper compression reading. If it's truely 90 PSI, it'll never start. You're chasing your tail until you establish a few baseline facts like compression and spark.
2000ssm6
Stihl User
Try pulling a 084 or equivalent without pushing the decomp button
That's what I did with the 125. It would never start so I tried it w/o decomp. Good googley moogley mother ******* I almost stuck it under the backhoe tire and gave it a lesson.:censored: I sold that saw for some crazy $$$$.
aztoad
ArboristSite Member
The Latest...New Compression Gauge
ok, so I decided after all these years I might as well go buy a reasonable compression gauge. I must admit I like it and don't question it's accuracy like the rented one.
Unfortunately, it is still only reading 100 psi. It goes over 50 psi in the first pull and jumps about 10 psi each subsequent pull and levels out just at 100 psi.
On another area - someone suggested that the ms290 compression should read above 90 but I certainly can't say that it is running yet either!
I also am trying some 91 octane fuel today - just in case before I take the whole thing apart...
I'll keep you posted.
ok, so I decided after all these years I might as well go buy a reasonable compression gauge. I must admit I like it and don't question it's accuracy like the rented one.
Unfortunately, it is still only reading 100 psi. It goes over 50 psi in the first pull and jumps about 10 psi each subsequent pull and levels out just at 100 psi.
On another area - someone suggested that the ms290 compression should read above 90 but I certainly can't say that it is running yet either!
I also am trying some 91 octane fuel today - just in case before I take the whole thing apart...
I'll keep you posted.
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Your wasting your time. That saw doesn't have enough compression to run. You'r going to have to pull the engine apart and find out what happened. You'll need rings at a minimum and I'm betting you'll find a scored piston.
Fish
Tree Freak
How does the rope pull with the plug out?
Remove the pull starter, and look at the flywheel/coil.
Find the magnets on the flywheel. With a pencil in the spark plug hole, rotate
the flywheel until the piston is at the top.
Now, where are the magnets located in relation to the coil?
Remove the pull starter, and look at the flywheel/coil.
Find the magnets on the flywheel. With a pencil in the spark plug hole, rotate
the flywheel until the piston is at the top.
Now, where are the magnets located in relation to the coil?
stihl025
ArboristSite Guru
Bought my compression tester at Harbor Freight for $10 or so (I think it was even less). Has the Schrader valve in the tip with a pressure release near the guage. Not the best or the most accurate, but it puts me in the ball park of what the saw is doing.
I have recently worked on an old 029. It only had between 110-120 psi compression cold, and it was hard to start and even harder to keep running. If yours is only reading 90-100 psi, then fuel delivery is the least of your problems. I would immediately pull the muffler and have a look at the cylinder wall and piston. Any scratches will tell the story...
