Chainsaw Repair

How To Basics - Carb Fixes + Mods - IPL and Service Manuals => Stickys of How to Basics commonly ask questions => Topic started by: KilliansRedLeo on March 27, 2014, 12:02:25 pm

Title: How to test the coil in a two piece trigger/coil ignition setup
Post by: KilliansRedLeo on March 27, 2014, 12:02:25 pm
This from the creative mind of 3000FPS. Putting it here so that it does not get lost.

Quote
3000FPS: When I was working on my Dolmar 119 I had no spark and it was a trigger and a coil set up.

What I did was to connect a 12volt battery to the input of the coil very quickly and remove it.   With a spark plug c-clamped to the top of the cylinder I could induce a spark.    The removing of the 12v is what makes the spark.  I used some jumper wires with alligator clips from radio shack.   You have to make sure everything including the negative side of the battery is grounding through the cylinder.

I found my coil was good the trigger was bad. I might also add is the contact of the 12volts has to be quick because a car battery has enouph amps to burn out the coil if you hold it on there.  You could also try a small 9v battery. Make sure the body of the coil if not mounted in the saw is grounded also.

Attached is a schematic of the connections.
Title: Re: How to test the coil in a trigger/coil ignition setup
Post by: countryhog on March 27, 2014, 12:43:39 pm
not sure i've heard of the trigger-coil setup. got a list of saws using that? pix?
Title: Re: How to test the coil in a trigger/coil ignition setup
Post by: KilliansRedLeo on March 27, 2014, 01:01:31 pm
not sure i've heard of the trigger-coil setup. got a list of saws using that? pix?

Sometimes referred to as exciter/coil or pickup/coil. Basically a two part electronic ignition where the actual pickup is separate from the coil. e.g. there is a box next to the flywheel and the coil is mounted else where. Used on many saws from all vendors Husqvarna 288, 61 many others, lots of Homelite, Dolmar, too many to note. But I am sure you have seen one of this type, just referred to in another way.

Look here post #23 for picture of Husqvarna 281 version

http://chainsawrepair.createaforum.com/husqvarna/288xp-no-sparkle/20/
Title: Re: How to test the coil in a two piece trigger/coil ignition setup
Post by: 3000 FPS on March 27, 2014, 04:57:55 pm
Yes the terminology probably is not correct.   Tim has a better explanation of the two piece coil set up.   Here is the picture of what was under the flywheel on my Dolmar 119.

I was looking at the IPL for the Dolmar 119 and I believe it refers to that module as a trigger.

(http://chainsawrepair.createaforum.com/index.php?action=dlattach;topic=3337.0;attach=6322;image)
Title: Re: How to test the coil in a two piece trigger/coil ignition setup
Post by: countryhog on March 28, 2014, 11:21:48 am
so you're telling me my early husqy 61 rancher has this kind of setup? L I B
Title: Re: How to test the coil in a two piece trigger/coil ignition setup
Post by: KilliansRedLeo on March 28, 2014, 12:44:31 pm
Yes, all three of my 61s have a two component system. They are 'gray top' saws. The earliest IPL for the 61 that I have (1980-02) also shows the two piece system. Given the 1980 date I am guessing that that saw would have been the white top 61 Rancher. Even the last of the 61s (orange top (S/N 1070001 And Below)) were still using the two piece ignition system. Saws after the above serial number use a single piece system.
Title: Re: How to test the coil in a two piece trigger/coil ignition setup
Post by: countryhog on March 31, 2014, 11:05:46 pm
L I B
Title: Re: How to test the coil in a two piece trigger/coil ignition setup
Post by: Al Smith on April 21, 2014, 05:04:46 pm
I've got a 281 Husky in the shed that uses a trigger unit .If I'm not mistaken J-red 630 perhaps, one of the only three of that brand I ever worked on .Whatever it was the trigger unit was up near the carb which I thought an odd place to put it .
Title: Re: How to test the coil in a two piece trigger/coil ignition setup
Post by: KilliansRedLeo on April 21, 2014, 05:10:02 pm
The 242XP, 281 and 288 had them on top, for what reason I'll never know but the 61, 66 161 and 266 had them down low under the starter.
Title: Re: How to test the coil in a two piece trigger/coil ignition setup
Post by: gregh on January 28, 2016, 10:11:55 pm
Definitive way to test a regular magneto for chainsaws?


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Title: Re: How to test the coil in a two piece trigger/coil ignition setup
Post by: 660magnum on January 28, 2016, 11:34:41 pm
Ignition system testing . . .

This does not talk about testing the coil itself. It came from the Dolmar 340/420 service manual. This saw had a single piece coil setup.

With the present day single piece coil pointless ignitions . . .

Accurate testing of the ignition module is only possible with sophisticated test equipment.

For this reason it is only necessary to carry out a spark test in the workshop.

A new ignition module must be installed if no ignition spark is obtained (after checking that wiring and stop switch are in good condition).
Title: Re: How to test the coil in a two piece trigger/coil ignition setup
Post by: 660magnum on January 28, 2016, 11:55:41 pm
With the old points type ignitions here are some typical parameters . . .  This is for an old Stihl 010

Condenser value .17 uf

Coil primary resistance .8 -1.3 ohms
coil secondary resistance 7.2K - 8.8K ohms

Point gap .012" - .016"

23 - 24 degress BTDC

Spark plug gap .020" - .025"

Coil to flywheel gap is the thickness of an appointment or plain business card - about .010"

Title: Re: How to test the coil in a two piece trigger/coil ignition setup
Post by: gregh on March 27, 2016, 01:48:26 pm
I have a home lite brush utter xl, that has a magneto and points as a peice part, and it won't fire. I set the points to .015 and still won't fire.


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