Husqvarna chainsaw Help Needed

[4rfam]

First let me say Hi to all since I am new to this forum. I am not a small engine repair expert, I have worked on and repaired things for myself and friend all my life. I have one now that leaves me scratching my head. My neighbor asked if I would look at his Husqvarna 141 chainsaw saying it would not start. I have check everything and it will not start. Hear is a list of what I have checked and done.
Checked to see if plug was firing, it was but replaced it anyway and is still firing.
Removed and cleaned the carburetor, still would not start, installed a new one still would not start.
Replaced the fuel line, carburetor is getting fuel
Found the impulse tube was bad replaced it still would not start.
Checked the compression with throttle wide open it was 115 and pressure holds.
Removed the muffler, cylinder and piston not scared looks good same from carb side.
Thinking ring my be stuck because I found carbine build up on the piston, soaked for 24 hours did not help
Checked the on and off switch works fine disconnected it anyway still would not start.

I am at a total loss, it has now become a challenge for me.
Next step is remove the cylinder and piston unless anyone out there can offer me some advice.

Help is needed open to any suggestions.

Thurman

 

[Medic21]

That is on the very low, possible not enough compression. 125 is the low end of normal.

My first thought was buy a Stihl .

The other thing is the crank seals, vac test it.

 

[dougand3]

I agree with marginal compression. Try a tsp of fuel in the plug hole and see if you can get a burp, maybe 2 sec run. If no joy, pull the jug and examine P, C & R. May only need P&R - cheap at $8. Pay attn to 40mm vs 38mm.

 

[4rfam]

That is on the very low, possible not enough compression. 125 is the low end of normal.

My first thought was buy a Stihl .

The other thing is the crank seals, vac test it.

I thought that might be the problem, what to get some other ideals before I went through that trouble

 

[4rfam]

I agree with marginal compression. Try a tsp of fuel in the plug hole and see if you can get a burp, maybe 2 sec run. If no joy, pull the jug and examine P, C & R. May only need P&R - cheap at $8. Pay attn to 40mm vs 38mm.

I tried the fuel in the cylinder and it would not fire, but I have not check the crank seals will work on that today.

 

[4rfam]

I agree with marginal compression. Try a tsp of fuel in the plug hole and see if you can get a burp, maybe 2 sec run. If no joy, pull the jug and examine P, C & R. May only need P&R - cheap at $8. Pay attn to 40mm vs 38mm.

This saw was built in 2003 according to the ser#, from what I can tell it takes the 40mm is there a way to verify that. By the time I finish this project the saw will be like new. And yes I agree get a stihl that's what I have myself never gave me a problem over 30 years old now.

 

[dougand3]

This saw was built in 2003 according to the ser#, from what I can tell it takes the 40mm is there a way to verify that.

With muffler off, insert a stiff piece of paper (or long matchstick or similar) marked at 38mm and 40mm. See which mark is just inside exhaust port. Much simpler after disassembled - measure piston with ruler or caliper.
The 14x saws are usually 40mm and 13x are 38mm.
Topends are quite cheap for this saw. - I'd change the whole shebang if any scoring or wear on cyl walls.

I tried the fuel in the cylinder and it would not fire, but I have not check the crank seals will work on that today.

If you pour fuel on top of the piston and can't even get a burp - crank seals aren't the problem. Well, MAYBE if there is a dime sized hole and all the fuel leaks out but that's a stretch.

 

[StihlKicking]

Have you checked to make sure the muffler screen isn’t plugged up?

 

[Corey]

I tried the fuel in the cylinder and it would not fire, but I have not check the crank seals will work on that today.

Well, there are only two reasons an engine won't run... either you're not getting fuel, or you're not getting fire. If you trust this fuel is good, then that rules out the fuel part.

 

[salecker]

Well, there are only two reasons an engine won't run... either you're not getting fuel, or you're not getting fire. If you trust this fuel is good, then that rules out the fuel part.

Need the third most important part...
Compression.
You should never start working on a questionable saw without looking at the piston.Pull the muffler and look through the port at the piston to see if it is scored. 115# compression is very low,but it could be your tester.Visual inspection of the piston is the first thing i do before i even pull a saw over if it is new to me.

 

[Zack R]

Is the inside of the cylinder wet from fuel? If its flooded pull the spark plug, open the throttle and pull the starter cord about 6 times to dry it out.
How old is the fuel mix? If its not fresh I'd start with a fresh batch.
Check that the spark arrestor is clean (propane torch will clean it quickly).
Verify the spark is good and the spark plug gap is correct.

 

[Corey]

Need the third most important part...
Compression. ...

That is part of 'fuel'. no compression means no vacuum, no fuel drawn through the carburetor, no fuel held close to the spark plug. Same way a dead battery / dead magneto is part of 'fire'.

The OP mentioned 115 psi, so that should at least run. Tablespoon of fuel in the cylinder should at least go 'poof' even if the spark plug is just held near the plug hole. (Don't ask how I know that to be true!)

If the saw isn't popping and sputtering with good fuel directly applied, I'd look on the ignition side.