PP4218A Won't Start

[Ikester]

Unfortunately I left fuel in the tank from last fall until now.  The saw won't start.  I have replaced the carburetor, spark plug, air filter etc.  Checking the ignition I do see a spark, but it's not as intense as on cars.  One post says if you can see a spark at all it's OK. So, it has air, fuel, spark and compression, how do I get it to start?  Appreciate all help.

[DHansen]

What did you do to confirm it is getting fuel?  Does if fire at all? 

[sawguy21]

Squirt some mixed gas in the carb throat, don't overdo it, and see if it fires. If it pops you have narrowed down the problem.

[Guydreads]

Is the fuel line connected lol???? Believe it or not, I have done that twice in 2 months. Yikes. The fact that it doesn't seem to fire seems surprising to me. Welcome to the Forum!

[Tacotodd]

How much compression does the gauge show?  

It's also possible that it has "slipped" time, as in "the flywheel spun" on the crank a little. It don't take much.

The spark and fuel and compression are a good thing, but it's got have enough compression and the timing also has to be correct. 

It's also got to get "enough" fuel" to continue to run once it's started. 

You appear to be on the right path to track down your problem.

I got to thinking, it's "possible" that you aren't pulling it hard enough. Don't get me wrong, cause it's happened to me before! I felt like a moron when I took it to my dealer who's also a friend of mine. We laughed when he got it started in 3 pulls! My fault and nobody else was to blame! No charge, probably because we BOTH took it in stride.

[Ikester]

Thanks for all the helpful replies.  The fuel line is connected and the primer works (at least the bulb fills).  I checked compression with 4 strong pulls and it is 25 lbs.  Don't know if that is good or bad.  The brand new spark plug had black residue on in after initial installation and 3 attempts to start.  I doesn't sound like it has fired though.  Haven't touched the ignition module (yet) so not sure if timing has slipped.  This sure seems more complicated than working on my first car (1956 Chevy).  Thanks again Y'all.

[sawguy21]

Umm, you need 125 pounds for it to do anything. Either the guage is toasted or the saw is.

[lxskllr]

My vote is on the gauge. The saw worked last time he used it, and I don't think the saw lost compression just sitting there. You'd feel it pulling it over too. Probably be as easy to pull over as a spinning top.

[Ikester]

Checked the gauge on my push mower and it read 80 lbs.  So I guess the saw is a paperweight now.

[Guydreads]

Well, first step in this case would be to remove your muffler obviously, and check for scoring there... If there's nothing, then you might want to try re-testing the compression to make sure you got a proper reading. If you still get 25 lbs. you probably have scoring on the intake or sides of the piston. My guess would be on the exhaust side, and usually that points to no oil in the gas, or overheating due to no load on the saw (dull chain, running it without bar and chain at full throttle (never recommendable) etc.) Let us know what you find out, please.