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Goober
29-06-2009, 10:28 AM
What is about chainsaws and them being hard to start.......

Anyway...I have a trusty Husqvarna 45 Special that has served me well to date, however at my last outing I may have got the fuel/oil mix a bit lean and each time she ran out of fuel, she was hard to start on refueling(usually was a good starter)till after about the third refueling she failed to start at all and lumberjacking was abandoned for the day.

Took the saw home and completley stripped down and thouroughly cleaned every componant. Only thing of note was some slight scoring of cylinder and piston in the area of the exhaust port. Fully reassembled and fueled her up. Still unable to start her. There is compression, there is a spark, and there appears to be fuel getting into the cylinder. But do you think she'd start, No siree!! There is just a hint of a cough of possible start then nothing.

There are two carbuerattor adjustment screws, but I have tried every adjustment to no avail.

Any suggestions from the combined knowledge of all my fridgee brothers?

Brian_UK
29-06-2009, 11:45 PM
OK, you have a spark, is that with the plug removed?

Q. Do you get a spark inside the combustion chamber under compression?

Are the carburetter jets worn?

Other than that I'm lost too.

Goober
30-06-2009, 04:08 AM
Spark is with plug removed from cylinder but making contact with cylinder block. Plug has been replaced.

No idea if it's sparking in the cylinder, would assume so.

Carbureter was striped and cleaned and no wear or tear noticed...

Thanks for the reply, was beginning to feel like I had swine flu or something....

TRASH101
30-06-2009, 08:44 AM
Hello goober

Whats the spark like i.e. bright blue, yellowish is it centered across the electrodes of the plug.

What deposits are on the plug when you take it out after trying to start it i.e. wet, dry or oily.

Is the choke working properly

Is the primer full

Goober
30-06-2009, 12:09 PM
Bright blue and centered

Wet

I believe so

Yes

Brian_UK
30-06-2009, 05:05 PM
Give it another twenty tugs and then throw it as far as you can. :D

Goober
30-06-2009, 09:40 PM
Oh believe me that it's getting close to being biffed, it sits in the corner of my garage and challenges me everytime I pass it. I give it a couple of pulls everytime I pass it in the vain hope that it'll have fixed itself....hate to give up on it.:)

Brian_UK
30-06-2009, 10:48 PM
Is the fuel fresh ?

Goober
01-07-2009, 02:23 AM
Yes, fuel is fresh.

TRASH101
01-07-2009, 12:01 PM
Hello again goob

Does it run fine when its started?

If so is it a reed block motor (warped reeds)

Check for leaky inlet manifold.

throttle position in start up.

Failing that it sounds like its a strip or skip job.:eek:

Have you tried heating the plug and a splash of fuel straight in the cylinder to get it started?

Goober
01-07-2009, 12:22 PM
[quote=TRASH101;151032]Hello again goob

Does it run fine when its started? Haven't been able to start it since it failed....

If so is it a reed block motor (warped reeds) ??????? No valves, reeds or any sort of inlet/outlet valve control...

Check for leaky inlet manifold.Not sure what your refering too?

throttle position in start up.As per previous starts when working ok

Failing that it sounds like its a strip or skip job. Have stripped it, but yes! is looking like more like a skip/biff job.:eek:

Have you tried heating the plug and a splash of fuel straight in the cylinder to get it started?Yes

My problem is......carberettors(or however you spell it) are a total mystery to me.....I understand the fuel/air mix ok, but don't get all the intricate chambers and diaphrams that make up a Carbere....