2lumbarleft
ArboristSite Operative
Gentlemen,
Once again I appeal to this learned august body for your sage advice. I recently purchased a Poulan PP4018WT chainsaw from a young man on craigslist stating that the saw ran well just last fall, but developed a problem over winter. The price was $50.00 and I wanted the case for my Echo CS-400-18 chainsaw. The case fits perfect, and that was worth $20 bucks to me. The bar and chain was probably worth an extra $15, so I figured at worst, I would lose $15 if I couldn't fix the problem.
The saw would start exactly the way it is supposed to, but would not accelerate to full rpm, as if starving for fuel. I checked and adjusted the splined carburetor jets to no avail. OK, time for the basics, plus a little extra. I changed all of the following; spark plug (properly gapped), fuel filter, fuel line, purge line, purge bulb and small fuel line from purge bulb to the carburetor. I rebuilt the carburetor, but that did not help. I then installed a brand new replacement carburetor and set the jets within normal ranges. The saw now starts and runs exactly as it had before I started all of this. I had previously inspected the cylinder through the spark plug hole and the exhaust side of the cylinder looked pristine as well as the piston. I removed the muffler, and viewed the piston, piston ring, and intake side of the cylinder. Everything looked like new. I ran a compression test, and the reading came in at 153 psi. The pre-mix gas I used was Husqvarna 40:1 synthetic fuel in a 32 oz can. Air filter is new, but makes no difference with it off. The muffler was checked for blockage, and it was like new. The rubber boot that the carburetor pushes into was in excellent shape, as well as the gasket below the carburetor. Right now I am suspecting that the timing is off, but that should be quite unlikely to pass factory release inspection, and the guy who had the saw said it ran good initially. So what is left? Coil and spark plug wire? It idles smoothly, so integrity of the spark plug wire should be good, and I would think that vacuum leak could be eliminated as well. Usually, I would think modular solid state coils either work or they don't. Maybe the spark is weak? Perhaps some of you mechanics have experienced these problems. OK panel of experts, have at it! Your help will be greatly appreciated.
Once again I appeal to this learned august body for your sage advice. I recently purchased a Poulan PP4018WT chainsaw from a young man on craigslist stating that the saw ran well just last fall, but developed a problem over winter. The price was $50.00 and I wanted the case for my Echo CS-400-18 chainsaw. The case fits perfect, and that was worth $20 bucks to me. The bar and chain was probably worth an extra $15, so I figured at worst, I would lose $15 if I couldn't fix the problem.
The saw would start exactly the way it is supposed to, but would not accelerate to full rpm, as if starving for fuel. I checked and adjusted the splined carburetor jets to no avail. OK, time for the basics, plus a little extra. I changed all of the following; spark plug (properly gapped), fuel filter, fuel line, purge line, purge bulb and small fuel line from purge bulb to the carburetor. I rebuilt the carburetor, but that did not help. I then installed a brand new replacement carburetor and set the jets within normal ranges. The saw now starts and runs exactly as it had before I started all of this. I had previously inspected the cylinder through the spark plug hole and the exhaust side of the cylinder looked pristine as well as the piston. I removed the muffler, and viewed the piston, piston ring, and intake side of the cylinder. Everything looked like new. I ran a compression test, and the reading came in at 153 psi. The pre-mix gas I used was Husqvarna 40:1 synthetic fuel in a 32 oz can. Air filter is new, but makes no difference with it off. The muffler was checked for blockage, and it was like new. The rubber boot that the carburetor pushes into was in excellent shape, as well as the gasket below the carburetor. Right now I am suspecting that the timing is off, but that should be quite unlikely to pass factory release inspection, and the guy who had the saw said it ran good initially. So what is left? Coil and spark plug wire? It idles smoothly, so integrity of the spark plug wire should be good, and I would think that vacuum leak could be eliminated as well. Usually, I would think modular solid state coils either work or they don't. Maybe the spark is weak? Perhaps some of you mechanics have experienced these problems. OK panel of experts, have at it! Your help will be greatly appreciated.