Poulan Pro PR5020 Please Help Coil Problems New Here

[brian041]

Hello All, I have been a lurker here for a while. Today I started my account I bought my first chainsaw. It was from an older gentleman who said it had sat in his barn for about 2 years still in the plastic case. I gave it a little ether and it came to life for a bit so I figured Carb just needing rebuilding. Now I'm down a rabbit hole after I installed the rebuilt Carb it ran great for about a day then nothing won't crank. So i I check for spark it has it but only when I pull the handle like I'm really trying to crank it, No spark when I pull it more lightly. It even came with a brand new oem Carb in the box so I figured Id switch that and still no luck. Basically I here these pr5020 with the 545-202-701 ignition coils are prone to failure. But when I pull the plug and crank on it I do get blue spark. Its a nice saw I just hope theirs an easy way to track down my problem. I Did check the gap on the coil it was slightly to much so i put back to 0.012 as specs say 10 to 14. Still same symtoms. Any Advice or direction would be much helpful I love these forums in this community. Thank you!

 

[Bob Hedgecutter]

Yes, you will not generate enough current to power the coil at a slow speed rotation.
From memory it requires around 600 RPM of the flywheel to generate spark at the plug.

Ether is not a good idea for a small 2 stroke that has sat a long time- the internals of the engine will be dry and ether starting fluid contains no oil- so basically the same or worse than straight gas running.

It may have sat in a box for two years because it was not running right so got shelved, you ran it for a day with the same issues and that was the straw that broke the camel's back.
These wee plastic saws are bad for air leaks.

Take the muffler off the saw and show us a photo of the piston as viewed through the exhaust port of the cylinder.

 

[brian041]

Yes, you will not generate enough current to power the coil at a slow speed rotation.
From memory it requires around 600 RPM of the flywheel to generate spark at the plug.

Ether is not a good idea for a small 2 stroke that has sat a long time- the internals of the engine will be dry and ether starting fluid contains no oil- so basically the same or worse than straight gas running.

It may have sat in a box for two years because it was not running right so got shelved, you ran it for a day with the same issues and that was the straw that broke the camel's back.
These wee plastic saws are bad for air leaks.

Take the muffler off the saw and show us a photo of the piston as viewed through the exhaust port of the cylinder.

I will pull the muffler off and post a pic of the internals. Now I did pull the plug and put my finger over the hole as I cranked it and it knocked my finger off easily, I know thats no compression test but I just wanted an idea if it at least felt like it had good compression. I know this model is known for having coil problems because of it being placed right against the head, I have come across several threads saying under compression this coil is known to fire weakly or not at all from heat damage and poor reliability from the coil. I do want to pull the coil and check it with a multi-meter I just need to find the proper way to do it and the specs it should read,

 

[Bob Hedgecutter]

In my opinion- "testing" a coil with a multi meter is pointless- it will show continuity and thats about it.
They either work or they dont. If it is failing because of heat, the saw will run as per normal for 10 minutes or so then splutter and die, checked immediately it will show no spark, only to spark again once cooled down.

My own methodology is- check spark, check fuel delivery to combustion area, confirm viability of piston/rings, check timing of spark and then pressure and vacuum test the engine for air leaks.

You did try a new known quality spark plug?

 

[Bob Hedgecutter]

What make/brand of spark plug is that and whats up with the Mickey Mouse HT lead to spark plug connector coil spring?