Problematic 044 Stihl

[02BNATDI]

First off: this is great site!
I bought a Stihl 044 used ~4 years ago (sorry I don’t know the vintage of the saw) for cutting up firewood, that has always been hard to start. The saw started kicking back when I went to start it, and couldn’t even pull the start cord without it flying out of my hand. So I put in a new NGK plug, carb diaphragm kit, and reset the gap on the coil to ~.011” a business card, it was hardly off. It initially started fine with a little stutter at idle, and I ran half a tank though it. The following day it doesn’t even offer to start, with hardly any resistance on the cord, like it lost all compression overnight! I don’t have a compression gauge, Is there anything I can check / do before I shell out too much money to have a pro look at it?
Thanks for the help!

New NGK plug
New Carb diaphragm kit
93 Octane with Stihl oil
Clean Muffler screen
Coil is ~2 years old

 

[fishhuntcutwood]

Does it have a decomp valve?

 

[ShoerFast]

Pull the muffler and take a look, ,,,,, was it considarable faster running after the carb kit?

Reason I ask, was it ran very lean the last time it ran?

 

[02BNATDI]

No Decomp valve.

I have not pulled the muffler to look for any damage. I don't believe the saw was running too lean, if anything too rich the way it binding and the way the old plug looked; and the carb was set exactly 1 turn out.

I appreciate the quick responses!

 

[thompson1600]

Do you have access to a pressure/vacuum test kit? Hard starting and loosing compression could be an air leak. If you don't have access to case testers for the oil seals, start by checking the impulse line for cracks/breaks or the manifold for cracks/breaks.

Tom

 

[02BNATDI]

Do you have access to a pressure/vacuum test kit?
Tom

I do have a Mity-Vac if that's what you're referring to, however please forgive my ignorance, I don't what / where the impulse line is. Possibly the one pressurizing the the gas tank? Nothing to check the compression with, other than my thumb over the hole ;-)

 

[thompson1600]

Impulse line goes through the tank housing and hooks to one of the leads of the carb. The other end connect to the back of the crankcase, right below the cylinder.

The manifold is the large rubber piece behind the carb that attaches to the back of the cylinder.

Check these for any signs of leaks/cracks/deterioration.

The mity vac will work fine for vacuum testing the case. (does yours do both vacuum and pressure?). To do those tests you need to block off the muffler opening with a piece of thick gasket material behind the muffler, or by somehow blocking off the exhaust port. There is a special piece (part # 1128 850 4200) that replaces the carb, about 20 bucks at a dealer, that you would hook the mity vac to and then you can pressure/vacuum test the crankcase and the impulse line/manifold area. Just use soapy water to spray on areas if the pressure/vacuum does not hold. On the 044 I believe you want to hold about .5 bar of pressure for 30 seconds, and for vacuum it should hold about .5 bar (but may drop a little and be ok) too.

The most usual thing on an 044 I have seen is either the impulse line or manifold being bad, or the oil seal behind the flywheel.

1128 850 4200

 

[Lakeside53]

If you feel little compression, start there... Do a comp test. Buy a gauge (make sure it has a valve at the plug screw-in tip) or take it to your saw shop ans ask then to test it on the spot - typically no charge, at least at my or Thalls store!. If less than say 130 (bad, but should still start), pull the cylinder. No magic in compression... Piston goes up, compression happens...