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ECHO Chainsaw Problem????


Giles's Avatar
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01-01-13, 11:03 AM   #1  
ECHO Chainsaw Problem????

I have worked on small engines for over 50 years and have never seen an engine, of any type, that I could not get running----until now!!!
As many of you are aware, major changes and improvements have been accomplished with ignition systems.
That's where I think my problem is.
The chainsaw is a CS330t that was given to me by a friend. He knew nothing of the history. and the saw is in above average condition.
Here's the situation---
Compresson is 160#
Ignition spark will jump 1/4"--STRONG
Carburetor is new and getting fuel. No different then the Original that I rebuilt.
Crank seals passed test.

This is the FIRST engine I have ever seen that will not make the first effort to start!!! Not even a "fart"!!!!! Not even with different volumes of starting fluid.
This absoluteny makes no sense and I strongly believe it is in the ignition.
I guess I would like a little education about how these new coils work and what controls the Ignition Before Top Dead Center?

 
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01-01-13, 01:44 PM   #2  
The current ignitions, referred as ignition modules are simply coils with a provision for doing what the point condenser did on the old style. The condenser was there to bleed off excess current to protect the points. The points provided for the ground/break ground. The latter triggered the release of the spark from the coil which was saturated from the magnetic field of the flywheel magnets passing through the pickups.

The setup in the ignition module prevents the backflow of the current to allow coil saturation before the release in the form of a high voltage spark.

If you are using original parts on the saw, so the timing of the flywheel is energizing the module as designed and there is fuel available in the combustion chamber, you problem is either the spark isn't strong enough to jump the gap in a pressurized environment in the combustion chamber, or you have it flooded, which happens often.

Starting fluid is not a good idea for a two stroke. I would shut off all the gas, empty the tank of fuel, then, with full choke, full throttle spin it about ten pulls.

Then, with no choke, full throttle another ten pulls. Then put a dribble of gas directly into the spark plug hole and with full throttle, no choke, see if it will sputter.

If it does, put the gas back in the tank and see if it will start with half throttle, half choke.

 
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01-01-13, 02:11 PM   #3  
I understand and agree with all you are saying. I have used compressed air to clear the system after suspected flooding.
I do not like to use starting fluid an any engine---but sometimes it is necessary.
I might add that I have discovered that if a "newer" engine hasn't been run in a while, these eloctronic coils can DIE.
You can lubricate the cylinder, remove the sparkplug, and spin the engine over with an electric drill and the coil will sometimes be "reserected".
Even tried this with this saw.
I bought a Makita DPC7311 concrete saw that had a bad ignition module.
I set the flywheel and coil up in my metal lathe and spun the flywheel at 2,000rpm and after app. 30 seconds, the coil started firing.
I installed components back on saw and it cranked in THREE pulls.
I have used the saw many times since.
Makes you want to go back to the old days when things were simpiler

 
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01-01-13, 08:55 PM   #4  
Certainly simpler in design, but I'd say the electronic jobs are a lot better. With fewer moving parts and a quicker coil saturation/fire sequence you can get the timing more accurate. Plus maintaining the points on engines was always an ongoing process. A set of points dealing with 8 - 10,000 rpms had about all it could handle in wear and point float.

The newer jobs have their problems, but nothing too chronic. It's just a matter of fixing them when they give out, I guess.

I can see where you might give the capacitor another chance with spinning it like you're talking about. It would depend how dead it was. Usually when the coil itself has gone south, you just about have to give it a funeral and buy another one.

 
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01-02-13, 03:56 PM   #5  
I rarely see a coil that sparks but is bad. Almost never happens, but it's possible. Two things I would suggest first: Check the flywheel key. I would suspect it to be sheared. Also, use a champion or autolite spark plug, even if the current one is sparking fine. Japanese and chinese plugs (especially NGK) often cause problems in small engines and appear to be working fine even when they aren't.


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