No Spark

[Syncro]

My lawn tractor suddenly stopped yesterday and I think it may be the ignition module. It has an 18 hp horizontal Briggs twin, about 13 years old. Its a simple machine and everything is easy to reach. I checked the three safety interlocks and they are working fine, the engine spins good so the starter circuit and battery are good. No spark to either cylinder, so now what? The manual refers to an ignition module, can anybody shed a little light on this? I never got into small engines so kinda lost where to start. I may have to take it in to our local small engine shop, sure like to fix it myself, but gotta so something soon as the lawn knows the mower is broke and is growing extra fast

 

[jinman]

All the safety interlocks do is send a ground to your ignition module, the same as turning off the key. If you can find the wire going to the ignition module, it probably has a connector in it. Disconnect that and see if the engine will start. If it does, it's in the interlock/ignition system somewhere.

I have an old MTD mower and a more modern TSC Huskee with a twin-cylinder Briggs. Both of them have had to be disconnected from time to time due to intermittent interlock malfunctions. I'd give disconnecting a try before you start taking the engine apart to get to the module. When you want to kill it, just reconnect the wire.

 

[Syncro]

All the safety interlocks do is send a ground to your ignition module, the same as turning off the key. If you can find the wire going to the ignition module, it probably has a connector in it. Disconnect that and see if the engine will start. If it does, it's in the interlock/ignition system somewhere.

Thanks for the idea, but I've already tried that. For a while there I thought that might be the problem because when I un-plugged the seat switch I still had ground, but I discovered that there is a small micro switch inside the connector that makes contact as soon as the connector is unplugged, I gues to thwart off people disconnecting on purpose. Anyways, all the interlocks are OK. I asked my local repair shop about it and he says that the modules seldom outlast the engine, so I bit the bullet and brought it in. I'll post the outcome.

 

[Syncro]

Spark problem was the module, as I had supected. Not a cheap fix though, $120, but it did the trick.

 

[chabat124]

Spark problem was the module, as I had supected. Not a cheap fix though, $120, but it did the trick.

You say not a cheap fix. Maybe not, but sometimes it is just worth it to have someone else figure it out and get it done pronto. I can't tell you how many times I have overspent and become very frustrated throwing parts at a problem.

I am pretty frustrated with a water leak under a rent house right now. They fixed one leak and a new one sprang up. (galvanized pipe). I am hunderds in and now will be hundreds more. I would do it myself but there is very little room in the crawl space and as much as I hate to spend the money, I would hate being under there even worse.

I had an ignition module go out on our Civic one time $270.00.

I feel your pain.