Slightly O/T.. Lawnmower problem

Maybe the spark plug needs replacing.

"Cold Ethyl" > wrote

No, it`s not the spark plug unfortunately.(Already changed)

There`s no spark arriving on the spark plug lead ( proved by using a neon timing light tester )

Thanks anyway

Scott

This is the point I give up, and send it in.

Unless its a simple broken plug lead?

If it wasn't electronic, I would say it was the contact breaker or capacitor. I've no idea what replaces these in an electronic magneto, but it probably isn't repairable other than by a new electronic unit. Another possibility is moisture has got into the HV coil and the insulation broken down, but they are usually pretty well waterproofed.

I had a problem similar to this several years ago where the lawnmower sometimes ran erratically and then finally falied to start. I proved that it was due to no spark by taking out the spark plug, resting it on the metal engine and looking for a spark when the starting cord was pulled..

I eventually traced the fault to the switch that controls the switching off of the engine . This is connected via cable to the operating lever on the handlebars that you have to hold ON when you are using the mower.( When released , it earths the spark plug lead via this switch preventing firing at the sparkplug and also applies a mechanical brake to the flywheel)

It was fairly easy to prove using a multimeter and if I remember correctly , it was due to a sticking plunger that operated the microswitch. I cured it by cleaning it up and lubricating it with a small squirt of WD40.

It`s ran OK ever since.

If that`s not the problem , then I would suspect the magneto , but magnetos are usually very reliable.

If you want any further info then email me and I`ll see if I can help as I`m still using the mower.

Vic

I have an ISEKI mower with a Honda engine, I have had the electronic 'Ignitor' chip fail twice.

There is no spark at the plug when it happens - I know there are loads of other reasons that could be the cause, but as it has happened twice, maybe they are unreliable on Honda small hp motors

Rick

Thanks for all the suggestions , especially the last one.

The fault was due to the operating spring on the engine on/off switch being undertensioned.

This meant that the switch was never fully operated , even when the handle was pulled in the full on position.

I`ve taken it off and retensioned it and it now runs OK.

Thank goodness for that. I had visions of faulty electronics in the magneto circuit so it certainly doesn`t pay to jump to conclusions.

I bought this version of lawnmower mainly because of the well known reliability etc. of the Honda engine

Thanks everyone.

Scott