I answer a lot of posts on here about mags, and have worked on LOTS of them over the years, especially the H-4's.
I don't do it as often as I used to.
A customer had "dies when hot problems" with his "A", and I needed to put a coil in it.
<img src = "http://i167.photobucket.com/albums/u125/27Grainfield/061008_144800.jpg">
I yanked off the cap, rotor was pointing straight up. GOOD ENOUGH. Easy enough to put the mag back on that way.
I took the mag with me, and proceeded with replacing the coil. As usual, the coil was STUCK on it's laminated "armature". I should have just sawed it off, but tried to press it out, "delaminating" the core!
Fortunately, I had a "donor" mag handy, and grabbed it's coil core.
Got the coil all in place, installed new points, and CAREFULLY set them to .013", using a dial indicator, rather than taking a chance on touching them with a feeler gauge with possible oil residue.
I took a look in the little rotor drive gearbox. Someone had set the gears up with the rotor one tooth retarded,so I corrected that.
I went to the customer's place today, and re-installed the mag.
Someone had previously installed the cap upside-down, and it was "cocked" a little, not sitting down on the locating pin, so I turned it 180º and swapped the sparkplug wires accordingly.
I had made a match-mark on the mag flange and mounting flange, so the timing was back where it was. I then tried to find the timing mark on the flywheel, to no avail.
Just to verify it was CLOSE, I started the tractor, which INSTANTLY fired up, and ran pretty well.
Shut it down, and tried AGAIN to find the timing matk on the flywheel. NO USE.
I pulled the #1 sparkplug, and used a length of wire to follow the piston travel, and find TDC.
THEN, I took another look for the timing mark, and there it was, the most faint line you could ever see. I marked it with a red paintpen, then proceeded to check the timing. The mag was tripping quite a bit AFTER TDC, so I reset it to trip JUST after TDC (in case they ever crank-start it).
Boy, does that little engine PURR now!
It's been rainy here, I hope the weather holds, as they plan to mow with it in the morning. I HOPE the new coil fixed the "dies when hot" problem!
I don't do it as often as I used to.
A customer had "dies when hot problems" with his "A", and I needed to put a coil in it.
<img src = "http://i167.photobucket.com/albums/u125/27Grainfield/061008_144800.jpg">
I yanked off the cap, rotor was pointing straight up. GOOD ENOUGH. Easy enough to put the mag back on that way.
I took the mag with me, and proceeded with replacing the coil. As usual, the coil was STUCK on it's laminated "armature". I should have just sawed it off, but tried to press it out, "delaminating" the core!
Fortunately, I had a "donor" mag handy, and grabbed it's coil core.
Got the coil all in place, installed new points, and CAREFULLY set them to .013", using a dial indicator, rather than taking a chance on touching them with a feeler gauge with possible oil residue.
I took a look in the little rotor drive gearbox. Someone had set the gears up with the rotor one tooth retarded,so I corrected that.
I went to the customer's place today, and re-installed the mag.
Someone had previously installed the cap upside-down, and it was "cocked" a little, not sitting down on the locating pin, so I turned it 180º and swapped the sparkplug wires accordingly.
I had made a match-mark on the mag flange and mounting flange, so the timing was back where it was. I then tried to find the timing mark on the flywheel, to no avail.
Just to verify it was CLOSE, I started the tractor, which INSTANTLY fired up, and ran pretty well.
Shut it down, and tried AGAIN to find the timing matk on the flywheel. NO USE.
I pulled the #1 sparkplug, and used a length of wire to follow the piston travel, and find TDC.
THEN, I took another look for the timing mark, and there it was, the most faint line you could ever see. I marked it with a red paintpen, then proceeded to check the timing. The mag was tripping quite a bit AFTER TDC, so I reset it to trip JUST after TDC (in case they ever crank-start it).
Boy, does that little engine PURR now!
It's been rainy here, I hope the weather holds, as they plan to mow with it in the morning. I HOPE the new coil fixed the "dies when hot" problem!