Thanks Mick
I will go over the fuel system and try fresh plugs.
SG

With my walk behind B&S powered also u/s at the mo, I am beginning to think sheep might be an idea....

Hi Shortgrass24, and welcome to TGMF

Those Honda's are notorious for coils dying, but like you said not normally both at the same time unless there was a major wiring fault on the machine.

As you said, the thin wire from each coil does the job of stopping the engine when grounded.  That wire is split into three via a diode module between the coils.

The engines are also very fussy on spark plugs, I have seen plugs that spark on one engine and not on another. So if it hasn't had a new set for a while I would try that first before throwing money at coils. Also make sure it's getting fuel, especially as it's not been run for so long.

I would probably recomend the honda izy too, the 18" I found to be a better machine, I use a toro now, but I have come away from mowing lawns and gone down the root of repairs.

Hiya Mick, I tell everyone the same, I was working on a strimmer a friend brought me today and wouldn't run, first thing I did was check fuel and it was like jelly in the bottom of the tank, I cleaned that and cleaned the carb and it worked like it should.

My first plea for help, so be gentle..
I have a Honda ride on, left here by a friend after selling their nearby house. It did work, but has been stored for about a year.
Put some fresh petrol in and battery. Doesn't want to start, so looked at the usual, but found that there appears to be no spark after I put a spare plug onto one lead.(plug works, checked)
Now, I always assumed that the leads off the ignition coils from such small engines were earths, to stop them.
So I disconnected them, but still no spark? Tried to check the switch wiring and that agreed with the earthing idea.
So, bit puzzled. One coil might fail, but both? Looked on line for wiring, but diags don't help much.
SG

New here, as looking for a bit of advice.
Live halfway down France on the left side.
Interests:
Restoringt our old pile and keeping the vegitation under control. Time off, like to muck around with wooden sailing boats, but small enough to trail to different places. Currently finishing a small cruiser.
Have spent time with small aircraft and building road/track cars from scratch.

Hi Mick, thanks for the suggestion. No I have not tried that - I will give it a go 👍

Mick I'm looking forward to giving it a good smack tomorrow lol, it is frustrating, but I'm learning as I go,
The smaller lawnmower engines like a Mountfield are so easy to repair, but this is way past my skill set, with help from you like this put my mind at ease.

Once it's off I will give it a clean and see what happens. Didn't want to give in to easy yet.

Cheers

Andy

Hi Will, and welcome to TGMF.

Have you tried removing the spark plug and see if it spins over ok like that.  Sounds to me like the decompressor on the camshaft isn't working, so as soon as it hits compression it stops. You could also try turning the engine backwards by hand half a turn or so, and then try engaging the starter again.

It could be valve clearances need adjustment, but to be honest this doesn't normally just happen suddenly unless something comes undone.

 

I have a husqvarna tc138 and am struggling to get it to start.
When I turn the key the starter motor activates and does an initial attempt at spinning the engine but quickly grinds to a halt. The battery voltage is fine - fully charged. I have bypassed all wiring with jump leads and the same issue occurs ( I have also done this and removed the positive connecting cable to check this was no grounding out). I have taken the starter motor off and appears to be working fine, spinning freely and fast under the battery voltage. I am now thinking it might be something to do with the flywheel. When the starter motor spins it sort of grinds to a stop (very quickly). I have to manually release it by moving by hand. This seems to release the pressure in the piston and then I can try it again but then same problem.

It was working fine last year but at the end of the season the belt came off so I have just put that back on. It has been sat under a cover over the winter (not ideal) hence my thinking it was an electrical issue. I am at a bit of a loss now. Anyone have any ideas?

Thanks!