Kradebaugh73
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I understand that. Revb had said to check the actual plug wire.
Out of curiosity, what is that piece of equipment called?
John deere gx75, scratching my head.
- Thread starter Kradebaugh73
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Out of curiosity, what is that piece of equipment called?
Actually don’t know. Looked into getting one when they started to change over to the triggered coils while teaching and my research at the time said three things. One, most shops are not going to have them. Two, cost was not going to go down, due to different types at the time. Three, if you teach students to understand basic electricity and how the electrical system on a small engine works, there really is no need for one.
From an FC290v engine manual.....
Engine Kawasaki FC290V FC420V & FC540V SM #492-4210.pdf
Service manual for single cylinder engines 87 pages 18.05MB Part 1 of 5 25 of 87 pages 2.96MB (General info, Specs, Wiring, Maintenance, Trouble shooting, Control system, Air cleaner, Carburetor) Part 2 of 5 14 of 87 pages 4.79MB (Recoil starter, Elecric starter and charging) Part 3 of 5 13 of 87...
www.wheelhorseforum.com
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bertsmobile1
Lawn Royalty
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YEs
You buy an osilloscope , a variable intensity & direction flux generator, a pulsing signal generator & a HV pulse counter
Total cost is around $ 20,000 for cheap stuff and not much change from $ 100,000 for the good gear .
Krautkrammer are a bit behind at the moment but I can get you some demo gear pretty quickly if you really want them
Or you could just replace the $ 40 coil
I use my old lathe to spin up flywheels and mount the coil on the tool post holder if I have to test one off a mower but most times I test on mower
The modern magneto coils have no points , remember points ?
Well since 1959 they started to be replaced with a solid state switch called a Hall Effect Trigger
Google it and see all of the different electrical variations then work out how you would go about testing them .
How good is your understanding of DC circuits ?
Just in case you'd like to get way into the weeds.....here's how the coil works at the granular level.
Here is the companion video of the one I posted about "getting into the weeds" on this subject......a good explanation of coil failure modes.
bertsmobile1
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Amazing.
While TRS's videos are generally good , his magneto coil failure video is rather poor
Now I only have 11 years of experience with modern mower coils but in that time at least 75% of the failures have been because the Hall Trigger was toast and that was probably a cooked transistor , some thing that he totally ignored in both of the linked videos
I rarely link his videos because they tend to be way too long and his almost monotone presentations are enough to send the viewer to sleep which is a shame because he ( or some one at least ) does a lot of work creating all of those graphics & animations .
Before they shifted the triggers into the coil envelope it was easy to check what part had failed by substituting a known good trigger & I modified a few to use for diagnostics with aligator clips .
Again about 3/4 of the time the chip was bad which is understandable because the transistors used in the stand alone modules are quite electronically fragile
The rest of the failures are split almost equally between a short in the windings & a bad HT lead / plug cap
Note I probably have only bothered to break out about a dozen or so coils to check what actually went wrong if the HT lead ohmed out OK .
OTOH I used to pick up 50 or so Victa push mower a year when I ran the courier business & paid my driver $ 20 for every one they picked up from road side clean up piles
Of those just about every one that had a no spark problem was down to the external trigger unit or the wiring associated with it and in a lot of the cases it was nothing more than the rivet used to hold ( and ground ) the unit had loosened
I loved them a 05¢ rivet and a $ 20 ( or free ) mower became a $ 100 sale
And I have been refurbishing these mowers since 1965
While TRS's videos are generally good , his magneto coil failure video is rather poor
Now I only have 11 years of experience with modern mower coils but in that time at least 75% of the failures have been because the Hall Trigger was toast and that was probably a cooked transistor , some thing that he totally ignored in both of the linked videos
I rarely link his videos because they tend to be way too long and his almost monotone presentations are enough to send the viewer to sleep which is a shame because he ( or some one at least ) does a lot of work creating all of those graphics & animations .
Before they shifted the triggers into the coil envelope it was easy to check what part had failed by substituting a known good trigger & I modified a few to use for diagnostics with aligator clips .
Again about 3/4 of the time the chip was bad which is understandable because the transistors used in the stand alone modules are quite electronically fragile
The rest of the failures are split almost equally between a short in the windings & a bad HT lead / plug cap
Note I probably have only bothered to break out about a dozen or so coils to check what actually went wrong if the HT lead ohmed out OK .
OTOH I used to pick up 50 or so Victa push mower a year when I ran the courier business & paid my driver $ 20 for every one they picked up from road side clean up piles
Of those just about every one that had a no spark problem was down to the external trigger unit or the wiring associated with it and in a lot of the cases it was nothing more than the rivet used to hold ( and ground ) the unit had loosened
I loved them a 05¢ rivet and a $ 20 ( or free ) mower became a $ 100 sale
And I have been refurbishing these mowers since 1965
