Husqvarna 445 only runs at WOT. STUMPED!!!

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dawgslife

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I just purchased a Husqvarna 445 a few days ago. Seller said it may need some carb work. It started exactly like my 450 then stalled so I purchased it for $80 figuring all it needed was a good carb cleaning. Cleaned the carb which was spotless and had the same issue. Swapped carbs with my 450, same issue. Almost seems like its shutting off. Primer bulb is good. Fuel lines and fuel filter are like new. Tried adjusting the carb, same results. The low adjustment did nothing. The high adjustment worked as it's supposed to. Swapped fuel caps with the 450, no change. The strange thing is it will run at WOT, but thats it. It's running hot and lean at WOT. New spark plug is white. I sprayed carb cleaner around the intake at WOT but that didn't do anything. Compression is 122 cold. The saw literally looks brand new. Another issue I noted is that the bar oil is literally pouring out of it especially when its running. Additional info: no scuffs or scrapes on the piston on the exhaust side, impulse line, intake boot look perfect. This one has me stumped! Would a bad seal on the crankshaft cause this kind of running issue? What is good compression for this saw?? Any help would be greatly appreciated!
 
These are pretty easy to get apart...id run the cylinder off and do seals and reseal the cylinder.

Sent from my LM-G820 using Tapatalk
 
Do what RED said.Also remove inlet manifold to check the fine seals in there.
 
I agree. Has to be an air leak somewhere. Thanks for the responses gents. I'm going to disassemble the entire saw tomorrow. I'll post what I find.
Thanks Again
 
Pulled it apart, inspected everything all looks literally like new. Hone marks in the cylinder still visible. Need some input on what to replace. I was going to order a new ring, base gaskets and seals. Am I missing anything? On a side note the base gasket is hard as a rock and the crankshaft seals slid off with ease if that means anything.
Thanks for any input
Dave
 
Seals and a gasket..youre there why not.

Sent from my LM-G820 using Tapatalk
 
Sure sounds like an air leak to me as well. Good luck getting it sorted out. Next time before you tear it down, spray some WD 40 around the crank seals, intake boot/gasket etc while running and see if RPM changes
 
Thanks for all the great advice. Still waiting on the parts somewhere in USPS limbo. Hopefully get the soon!!!!!!!!!!
 
What you should do when an air leak in suspected is pressure test the crankcase and go around the saw with a soap solution BEFORE taking anything apart. Can't tell is a seal is bad by looking at it afterwards.
 
Are you sure you had the throttle linkage hooked up correctly? Did you try backing off the idle screw? Just a thought but It sounds to me like the throttle wasn’t returning to the idle position. I’ve never had a motor rev uncontrollably because of an air leak.
Typically an air leak will cause hard starting, slow return to idle, heat, and pinging.
Was there any sign of damage to the piston?
 
Also remember this saw is stratocharged and sometimes the plate for the strato can stick open
 
Hey Gents

SOLVED - Replaced the ring, base gaskets and crankshaft seals. Runs perfect. I don't know if it was a combination of all three or not. I believe it was the crankshaft seals. Both slid off very easily. The new ones I used some oil and pushed them on. The others were sloppy compared to the new ones.

Thanks for all the help!!!

Dave
 
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