Echo PB580T backpack blower

Dsawyer44

Member
Joined
Sep 27, 2015
Threads
6
Messages
17
How can i tell if the fan keyway has moved throwing the timing off?
 

StarTech

Lawn Royalty
Top Poster Of Month
Joined
Feb 19, 2020
Threads
120
Messages
12,836
You have to disassemble the fan housing to get to the flywheel but I doubt the woodruff is sheared.

What the problem making think it could be sheared?
 

Dsawyer44

Member
Joined
Sep 27, 2015
Threads
6
Messages
17
I can't get the blower to fire at all. I bought it used. It has spark,compression 90 lbs,fuel. I even put gas in after taking the plug out. I also checked the muffler for a blocked spark arrester. Any help will be appreciated. Thank you. The blower is only a year old.
 

Tiger Small Engine

Lawn Addict
Joined
Dec 7, 2022
Threads
3
Messages
1,644
I can't get the blower to fire at all. I bought it used. It has spark,compression 90 lbs,fuel. I even put gas in after taking the plug out. I also checked the muffler for a blocked spark arrester. Any help will be appreciated. Thank you. The blower is only a year old.
If you are using the correct compression tester with a Schraeder valve, then 90 psi is low for a 2- stroke. Pull the muffler and check condition of piston, rings, and cylinder.
 

StarTech

Lawn Royalty
Top Poster Of Month
Joined
Feb 19, 2020
Threads
120
Messages
12,836
Probably been straight gassed. Check as Tiger suggests.

BTW the rule of thumb here is if the compression is below 100-110 psi it will not start. Need a tester with the correct Schrader valve at the end of hose at the cylinder; not at the gauge.
 

Auto Doc's

Lawn Addict
Joined
Sep 7, 2024
Threads
21
Messages
1,894
How can i tell if the fan keyway has moved throwing the timing off?
Pull the plug and the crank start head and then rotate the motor by hand with the flywheel to see where the flywheel magnet meets the coil. It should be at top dead center as the magnet just meets the coil. If it is off by a little bit, the key is sheared.

Also try to start it with the muffler removed to make sure the muffler is not heavy with oil coking. You cannot see what is inside the muffler. I have had to heat a few mufflers with a torch red hot to burn them out before. Customers who make their own oil/fuel mix tend to get carried away with the oil.

If you can look in the muffler head hole and see piston scoring, it has been run on straight gas in most cases and will need a cylinder and piston kit.
 

StarTech

Lawn Royalty
Top Poster Of Month
Joined
Feb 19, 2020
Threads
120
Messages
12,836
Question Auto. How do you see the flywheel?, since it is on the blower fan side of engine and it requires separating the backpack frame from the motor then fan box opened, the fan removed, and back half of fan box removed just get where you can see the flywheel. Even then you may not see the flywheel to coil
alignment.

Maybe some trick in the service manual.
 

sgkent

Lawn Addict
Joined
Sep 27, 2017
Threads
35
Messages
1,981
how did you test for spark? A plug can fire outside a cylinder but with compression fail. Were it me, I would buy a new fresh plug from a known good source and not Amazon. Then blow the cylinder out with compressed air to make sure it is not flooded. Pull it over a few times with the plug out, blow it out again THEN put a TINY amount of new gasoline in it thru the plug hole, put the new plug in gapped properly and see if it fires once or twice. Also, a plug can have spark when it screwed in but the center electrode be shorted to ground by carbon etc..
 
Top