benaford

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New poster here. I've enjoyed reading this forum over the years, but never made any posts, but I'm in need of some advice.

Background: A few years ago, I bought a Husqvarna YTH2348 with a Briggs engine for $500 from a guy who was moving away and needed to offload it. Right up front, he told me that it would not start without a shot of starter fluid, and that was true. It never started easily. I used the mower for grass cutting and leaf mulching for two seasons and then it just stopped starting all together. I attempted to rebuild the carb, but I could never get it to start and run again. I ran out of time an mental bandwidth to keep messing with such a fussy mower. Fast forward three years, the mower has been sitting idle, gathering dirt and rust under my deck because I just never got the energy tackle the repair.

Now, to the present day. I've decided to either get this thing running again or sell it as salvage. I pulled the hood, seat, and removed the deck and pressure washed the dirt and debris from the chassis. Then I parked it in my garage where I can spend time cleaning and digging into the motor. Yesterday, I pulled the carburetor, spark plugs (2), fuel pump, coils (2), valve covers (2), battery and starter. My plan is to work through a troubleshooting flowchart beginning with battery and working my way through the ignition system.

Engine Start Troubleshooting Flow:
1. Battery voltage: yes/no
2. Spark plugs: firing yes/no
3. Coils multimeter check: within range yes/no
4. Fuel pump pushing gas: yes/no
5. Carburetor (after getting a rebuild) sending fuel: yes/no

What else should be in my troubleshooting process? Should I remove the flywheel and sand it down? It's very rusty - see images.

Images

Thanks in advance for any wisdom you can offer. I've seen quite a few posts on here about this particular mower, but none about bringing one back from the dead. I thought it might be an interesting thread for someone else down the line.
 

Rivets

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Checking coil with multi meter NO. Today’s coils cannot be tested with a multi meter. After you reassemble everything, make sure that you throttle control cable is completely closing the choke butterfly. Can’t count the hard starting problem is caused by a cable which is not completely closing the choke on startup. Let us knew what you find.
 

benaford

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Wow, I didn't realize that you can't test these with a meter. What about videos like this one ? I've used multimeter to test coils on my pushmower - they aren't new but definitely not ancient.
 

Rivets

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Any ignition system which does not have points has a Hall Effect trigger embedded in the coil. You need a very, very $$$$ piece of equipment to test them. I know that everything you see on U-tube videos is the absolute truth, but this is the one time those idiots got it wrong.
 

ILENGINE

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Honda is the only one that I know of that list testing the coils with the meter and gives resistance readings.
 

benaford

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Any ignition system which does not have points has a Hall Effect trigger embedded in the coil. You need a very, very $$$$ piece of equipment to test them. I know that everything you see on U-tube videos is the absolute truth, but this is the one time those idiots got it wrong.
"I know that everything you see on U-tube videos is the absolute truth..."
This part got me laughing out loud - Thanks for the info. I'm learning something every day.
 

benaford

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What is the best way to get a replacement carb that will fit my exact model of mower?
 

Rivets

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Post all engine numbers, model, type and code and we should be able to find you an exact replacement.
 

StarTech

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First a lot times just the throttle cable needs readjusting as it might not be fully closing the carburetor choke.

And here is some info the new Briggs Magnetron Coils.

The configuration of new Magnetron coil may look like they removed the triggering device but in fact
it is just a redesign. Now to answer your question what is inside the coil.

1 ea 13mm x 34.5mm single sided circuit board.
5 ea SMD transistors.
8 ea SMD resistors, inductors, and/or capacitors.
(SMDs were destroyed upon board removal so actually identification wasn’t possible.)
1 ea D13003 transistor.

Primary Winding reading is 1.5 - 1.7 Ω.
Secondary Winding reading is about 6 KΩ +- several hundred ohms.

The kill terminal is directly connected to the non-ground side of the primary; hence, explains why you
or anyone else can NOT test the primary trigger circuit. Otherwords this means you can not test to find
out if a Magnetron coil is good or not without installing it in most cases unless you have a specialized
coil tester.

The D13003 emitter is connected to non-grounded side of the coil’s primary via two SMD resistors in
parallel with total resistance value of 1.0 Ω. (One these SMD resistors marked with the 1R0 code for a
1.0 Ω resistor was ½ watt size.) The collector is connected the coil’s primary winding that is grounded.
The base is connected to the rest of the trigger circuitry.

The coil’s transformer turns ratio is approximately 1 to 18 with secondary closest to the core.
In theory if the output D13003 transistor should short the collector-emitter junction and the coil’s
primary winding is still good the ohms reading will drop to 0.5 Ω - 0.7 Ω. If the coil’s primary winding
should short then the ohms reading should be near zero. If the coil’s primary winding should open then
the reading will be well above 1.7 Ω. Applying any voltage to the kill terminal would result in either
coil’s primary winding shorting or opening due to high current experienced. And this don't cover other electrical failures.
Applying voltage also can short out the electronics thus making the coil useless. It is also expected that a cold solder joint
connecting the external kill terminal to circuit board would lead to a non kill operation.
Also the high tension lead can be replaced if you wish to fight the glue considering the price of
aftermarket versions of this coil.

This info was acquired through the destruction of the new OEM version of this coil. It also explains the
configuration differences as they have gone to SMD trigger version.

Now for those that wondering why we put diodes in the kill circuit of the dual coil models it because of
the feedback loop created causing one coil to kill the other. This explains why they are destroyed when
12V is applied as these is no built-in reverse bias protection. Now with this in mind you might think
Kohler coils would be the same wiring. Not so as these diodes are incorporated into coil itself thus
preventing many of the problems that the Briggs have because they don’t incorporate these diodes.
 

benaford

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Post all engine numbers, model, type and code and we should be able to find you an exact replacement.
I apologize for my ignorance if I'm saying something dumb here, but I looked at the tag under the seat and this is what I have:
Product: 289571 Model: YTH2348 Serial: 042210A001055 (bottom right hand of tag is another number: 199684)
 
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