Help Stihl 201 tcm

[steele_109]

Hi I have 2 stihl tcm saws that belong to a tree service. Both were dropped or thrown from a bucket truck (I heard today one was thrown against a barn because it wasn't running right.)Sadly it's my job to fix them.I put a new top handle on it with wiring,new air filter and air filter cover. When I tried to crank it it ran and died over and over. I Thought it might be the carb so I took the carb of the other saw and put it on this one. It wouldn't even pop so I put the original carb back on it and nothing.So my question is did I screw something up in the coil.

 

[singinwoodwackr]

Hi I have 2 stihl tcm saws that belong to a tree service. Both were dropped or thrown from a bucket truck (I heard today one was thrown against a barn because it wasn't running right.)Sadly it's my job to fix them.I put a new top handle on it with wiring,new air filter and air filter cover. When I tried to crank it it ran and died over and over. I Thought it might be the carb so I took the carb of the other saw and put it on this one. It wouldn't even pop so I put the original carb back on it and nothing.So my question is did I screw something up in the coil.

Lol, sounds familiar…and why the service I work with switched to 355 Echos.
I fixed one that took a long trip as well. Wound up having to replace the carb as 3 rebuilds later, no joy.
you replaced the wiring harness so that’s fixed…that kind of abuse severs the wires.
how was the intake boot? Those can rip with that kind of trauma and it won’t run.

the ‘ran but died’ symptom sounds like new carb time to me…same problem. I talked to my local stihl guy where I get parts and he told me of the known carb issues. So, added another $90 to the rebuilds
I kept the old carbs to some day try and figure out what is wrong.

 

[steele_109]

Hi thank you for your reply. The boot was tore in half,replaced it. I talked to the dealer today he said try a squirt and see what happens.I ordered new fuel lines today. I will try them because when you pull them off the carb no fuel comes out it should squirt and it doesn't.

 

[singinwoodwackr]

Hi thank you for your reply. The boot was tore in half,replaced it. I talked to the dealer today he said try a squirt and see what happens.I ordered new fuel lines today. I will try them because when you pull them off the carb no fuel comes out it should squirt and it doesn't.

Pressure test the tank...may be a hairline crack.

 

[steele_109]

That's very possible but wouldn't at least seep a little with a full tank? I'll vac test it tomorrow.The dealer also told me to check the vent.

 

[ZeroJunk]

Check behind the little cover on the front of the saw where the connector attaches to the ignition module and make sure the connector is not broken or damaged.

 

[steele_109]

Hi thank you for your reply.The new top handle I put on the saw had new wiring in it that conection is new.It caused me to have to search for a tiny bit to change it.

 

[singinwoodwackr]

Hi thank you for your reply.The new top handle I put on the saw had new wiring in it that conection is new.It caused me to have to search for a tiny bit to change it.

Changing that harness is a pain

assuming you rebuilt the carbs…did you sonic tank the carb main body?
I’ve had a couple of late that had tiny bits of crud that just carb cleaner and blow-out didnt get.

 

[steele_109]

Hi no I have not cleaned the carbs yet.I did take them apart and everything looked good very clean.When I get it to pop off again,I will very possibly put a new carb on it.

 

[stihltech]

Using an inline spark tester, check to see if the ignition shuts off before it shuts down

 

[steele_109]

I did some more test on the saw.I popped the vent line nipple out the fuel tank and put pressure in the tank and it held,so the tank is good.I then put the tester in the tank vent line, if you vacume it no pressure, but if you put pressure in it would hold pressure. I put it back together and primed it and it fired.Now it's back to running for a couple seconds and dying. It acts like it's not getting fuel. The new fuel lines should be here by the end of the week.I should know more then.

 

[steele_109]

stihltech thanks for the reply. If I get time this afternoon I will try that, and let you know.

 

[sawfan123]

Does the saw have impulse? When the manifold tears, there's a good chance the impulse hose is damaged. You have to vac/pressure test it before you go any further.
The WERE solenoid problems, not carb issues. That's been addressed and fixed.

 

[ZeroJunk]

That impulse line does run a rather circuitous route.

 

[steele_109]

Just took it back apart tested it for vac and pressure it is good.The impulse line has no leaks.

 

[steele_109]

I checked the spark it dies out as the saw shuts off.

 

[SteveSr]

I checked the spark it dies out as the saw shuts off.

This would tend to indicate that the M-tronics is not happy. It will kill spark if it senses a problem with the wiring or other components like the solenoid.

Sure wish someone would share the M-tronic theory of operation / troubleshooting information (PM if necessary).

 

[singinwoodwackr]

I did some more test on the saw.I popped the vent line nipple out the fuel tank and put pressure in the tank and it held,so the tank is good.I then put the tester in the tank vent line, if you vacume it no pressure, but if you put pressure in it would hold pressure. I put it back together and primed it and it fired.Now it's back to running for a couple seconds and dying. It acts like it's not getting fuel. The new fuel lines should be here by the end of the week.I should know more then.

Carb issue, imo.
do you have a sonic tank? HF has them cheap. I’ve had 4 carbs in the last few months that a normal cleaning didn’t get fine crap out of the passages that the tank did.
if that doesn’t work you will need new carbs.
.02

 

[steele_109]

I'm hoping the fuel lines fix it,but if they don't then I'll put the carb in the ultrasonic.If that doesn't work new carb.But this carb is really clean inside not a spec anywhere nothing in the screen.But at the end of the day that doesn't mean anything.

 

[angelo c]

1.Change the solenoid. If that doesn't work...
2.Change the solenoid again. If that doesn't work see #1

Almost all the TC issues I've had were solved with a wiring harness replacing or an new solenoid and a RESET OF THE NEW SOLENOID.