[wygs]

Where can I find an ignition coil (new or used) for a Honda HT3810 lawn tractor? Nobody seems to make it anymore, although there are lots of the tractors out there, still in good shape. (It was very well built!) Someone might have one still in stock or in a "bone pile" somewhere.

[crigby]

Hi,
First of all there is a serial number break on the engine, not the machine frame. The two number I come up with are 30500-890-951(up to serial #1414934) and 30500-890-952.
The location I used is:
All Years HT3810 SA LAWN TRACTOR, JPN Honda Lawn Tractor IGNITION COIL (HT3810-K1-K2) Diagram and Parts
Peace,
Clarke

[wygs]

Hi,
First of all there is a serial number break on the engine, not the machine frame. The two number I come up with are 30500-890-951(up to serial #1414934) and 30500-890-952.
The location I used is:
All Years HT3810 SA LAWN TRACTOR, JPN Honda Lawn Tractor IGNITION COIL (HT3810-K1-K2) Diagram and Parts
Peace,
Clarke

It's hard to know how to respond, given this ASK system. We'll try this.

Yes, the engine is a "K1", with serial number G400-1402429. Are you suggesting that there may be parts out there if only we can get this determination right? Everything I've tried suggests that, no matter which classification it fits in, nothing is available.

[crigby]

Hi,
It would seem that you need the first part number. To double-check, there is a silver and black tag on the side of the engine, should have some other alphabetic characters on it that will make certain of the part number. There were also units with points/condensor and solid state.
Peace,
Clarke

[wygs]

Hi,
It would seem that you need the first part number. To double-check, there is a silver and black tag on the side of the engine, should have some other alphabetic characters on it that will make certain of the part number. There were also units with points/condensor and solid state.
Peace,
Clarke

I don't quite get it. I did not think finding the right part number was my real problem, since neither part is available. Someone told me Honda makes parts for 7 years which just fulfills US law requirements, then walks away from their equipment. This was made decades ago, but is in great shape. It seems a shame to make something so it will last for 40+ years but to support it for 7 years. Why would anyone pay top dollar for something built that well when the obsolescence built into it has to do with lack of support? No me; no more! As you might tell, I'm a little upset with Honda's approach to this. Anyway, if there is such a part out there, I'd love to hear about it.

[crigby]

Hi,
First do not assume that the part is not out there on someone's shelf. As far as I know the law is 10 years for engine-driven equipment. To my knowledge both of the numbers I gave you are available, but there are others.
I have been in this business for over 35 years and know how to locate parts in North America and Europe.
Please try to find the tag I spoke of and to ascertain whether your engine uses points. Those numbers go to the later model engines used on the machine, there are others.
Peace,
Clarke

[unaimedarrow]

I've run into the same problem as crigby. The ignition coil for either the K1 or K2 cannot be found.

I have a HT3810-K2. I had to pull the engine out of the chassis to get at the ignition coil (it involves a lot of dismantling). There are no points. It's an ignition coil period. There's probably some electronics in the plastic molding surrounding the coil but you can't get at the electronics without destroying it. I have the ignition coil off the engine sitting in front of me so that I can match it up visually with what may be found on the internet.

There markings on the left side of the engine (as you sit in the driver's seat) that identify it as a Honda G400 engine.

Tom

[crigby]

Hi,
I will give a link to a breakdown with the two part numbers on it. Please look for a flat area on the back or right side with letters and numbers stamped into it and provide those. See:
All Years HT3810K2 SA LAWN TRACTOR, JPN Honda Lawn Tractor IGNITION COIL (HT3810-K1-K2) Diagram and Parts
Peace,
Clarke

[unaimedarrow]

Clarke,
Appreciate your efforts. However, I placed an order with Boats.net (the link that you provided) for the part more than a month ago and after a week received an email from them indicating that they could not fill the order. Since then I have received the same response from a number of sites. The sites that list the ignition coil have not updated their web sites to reflect the unavailability of the part; although their websites show that they have the part ---- in reality they don't have it. From what I have found, Honda has discontinued the part and no one, as of yet, has picked it up in the after market to manufacture a replacement.
Regards,
Tom

[Stratmando]

There is a Guy on Ebay parting one out, you might find that and more for your Tractor:
Honda HT3810 lawn tractor | eBay

Did you do any Test on the Coil(Primary and Secondary Resistances)?

[unaimedarrow]

I did measure the resistance of the coil and spark arrester. The coil was about 7.5K ohms and the spark arrester was 10.2K ohms. However, I don't know what the resistance should be; so for all I know the two parts of the ignition coil could both be bad or both be good or one of them is bad and the other good.

By the way, I don't know how a spark arrester works so for all I know it should be 10.2K ohms or thereabouts. Also, I am pretty certain that there are electronics in the assembly of the ignition coil so that 7.5k ohms might be the correct resistance as well. If the ignition coil was a straight coil with no electronics then the resistance should be zero at first and then build up to infinite as the coil charges.

Tom

[Stratmando]

Never seen them climb, most I see have a high and a low resitance for primary and secondary windings, a capacitor will charge, then slowly drop.

Yould could build a little coil tester with the old style capacitor's used in the older ignitions(points), a normally closed switch, or set of points, a 12 battery source, and your coil with plug and plug wire attached.
After you apply power, the plug should fire when you OPEN the points/connection.
I would test before replacing.

[unaimedarrow]

Hi - the picture shows what the ht3810 ignition coil looks like. Two wires, one to the ignition and I assume the other goes to the regulator where it supplies the power to charge the battery.

There are no points, there is no visible condenser. There must be electronics in the ignition coil assembly to perform the function of the points and probably a condenser is in there as well.

It's hard for me to see that a tester could be built to test it outside of the motor. When it was in the motor, I connected an ignition timing light to it. When I could get the engine to run, I would see the timing light fire. When I couldn't get the engine to run and I was turning the engine over with the started the ignition timing light did not fire. Now I can't get the engine to run at all and the ignition timing light does not fire. Hence, I think I have a bad ignition coil (as you can see it's got to be more than just a coil).

Tom

[Stratmando]

Ignition system - Wikipedia, the free encyclopedia

After you are there, scroll down halfway to the color diagram and it shows how you could test the coil, instead out of the coil to the distributor, test out of the coil directly.
It is a coil to fire your Plugs, they don't charge the Battery, That would be your Rotor and Stator at the end of your crankshaft.

[crigby]

Hi,
As is sometimes the biggest problem with Honda, at times the part number can be superseded. Often it is not apparent except to an old Honda Pro(which I am not.) After some time searching and the assistance of someone who worked for a Honad dealer for many years, I came up with a part number that some change to; 30580-890-732 which seems to be available for a usual Honda price, about $250 and at:
Module-Ignition Control- Cdi [30580-890-732] - $230.82 at eReplacementParts.com
Peace,
Clarke

[unaimedarrow]

Clarke,
Appreciate your efforts again, but there seems to be a world wide conspiracy to make this part unavailable. I went to the link you provided to find this message: This part is no longer available from the manufacturer.

Tom

[Stratmando]

Did you contact the guy on Ebay that was parting out that same model?