Echo PB-403T Blower Shut Off After 5 Min WOT

[izzrock68]

After I replaced a bad carburetor on my Echo blower PB 403T and adjusted it would now run. However, when I run it at WOT it runs perfectly but it will bog down after 5-6 minutes and then shut off. I can restart it most of the times pretty quickly. I cleaned spark arrestor, muffler to motor opening, new gas filter, gas line, new gas/Echo oil mix and a new plug. I ran it with the cap off to avoid any air lock issue with the same bad result. Any help would be appreciated.

 

[bertsmobile1]

Firstly the cap has to be on because the fuel pump pressureises the fuel tank to PUSH the fuel into the carb
People think the pump sucks but it does not .
I like to use an in line spark tester to establish if it is a fuel or ignition problem
If the tester flashes till the engine stops then it is a fuel problem
If it stops flashing then the engine starts to slow down & stop then it is an ignition problem.

If it is a fuel problem it could be a plethora of things from a bad fuel line, partially blocked INTERNAL fuel strainer , hard metering diaphragm, air leak ( cube carbs & fuel tanks are a closed circuit pressuried system ) stuck / dirty metering needle, partially blocked H jet, leaking impulse circuit etc,etc,etc,etc etc
The Echo manual is 44 pages & I have no intention of retyping it here

 

[izzrock68]

Firstly the cap has to be on because the fuel pump pressureises the fuel tank to PUSH the fuel into the carb
People think the pump sucks but it does not .
I like to use an in line spark tester to establish if it is a fuel or ignition problem
If the tester flashes till the engine stops then it is a fuel problem
If it stops flashing then the engine starts to slow down & stop then it is an ignition problem.

If it is a fuel problem it could be a plethora of things from a bad fuel line, partially blocked INTERNAL fuel strainer , hard metering diaphragm, air leak ( cube carbs & fuel tanks are a closed circuit pressuried system ) stuck / dirty metering needle, partially blocked H jet, leaking impulse circuit etc,etc,etc,etc etc
The Echo manual is 44 pages & I have no intention of retyping it here

Wow, thanks so much for your quick reply...I think?...you were pretty wordy with your reply so why not type the 44 pages for me.... thanks Mr. Wonka, you were a big help!