Engine problems.

Since getting home, I've had the chance to sort out my outboard once and for all. I hope...

The problem has been ignition-based. During the trip various "repairs" had made a difference. Cleaning up and setting the points, insulating the cracked wire to the condensor, new spark plugs, etc.

At home I'd got an almost complete engine for spares, the snag was that it had electronic (CDI) ignition where mine was the old points and condensor setup.
So I thought it would be better to upgrade the one I was using with the CDI setup from the old one. Couldn't use the other engine, it had a cracked engine block.

A quick look and things appeared fairly simple, the extra bits bolted onto the block, the pulser coil fitted where the points went, etc.

I might have been a bit wrong again!

Pulled off the camshaft pulley to swap the points out. The pulser coil didn't fit - the casting on the cylinder head was different, only slightly, but different.
So that'll be a change of cylinder head as well then!

The donor engine had a cracked block, this had been due to a seized and broken stud in the cylinder head. That meant I first had to drill out the broken stud, another job on the list...
While doing that I worked out why the previous owner had been trying to remove the head. The internal water passages were blocked with salt/calcium deposits, this had probably caused overheating and failed head gasket.
So cleaning the passages out was added to the list!
A couple of days later and I had a usable head.

I didn't have a head gasket for a rebuild (still waiting for that) so decided to leave what was left of mine in place and bolt the thing together temporarily so I could at least get the electronic ignition together and working.

So, head back on, pulser coil fitted, cam pulley bolted on.

The flywheel had to come off next, so I could change the ignition coil under there.
It actually came off easily and the parts swapped without a problem!

Then there were a couple more bits to fit. The CDI unit bolted onto the inlet manifold. Mine didn't have the casting to bolt to, so had to swap that with the one from the other engine...

Then there was the reverse switch. Of course, mine didn't use one at all. Fitting that included swapping the gearchange linkage and pivot arm!

Minor one, the stop switch connector was different, so chopped  off mine and fitted a bullet connector to match.

Eventually the wiring matched the diagram I had, so I fitted the spark plugs into the leads, held them against the engine and pulled on the starter cord.

It sparks!!!

Good big sparks, for the first time since I've had the engine.

So yes, you can convert an old Honda 10hp 4 stroke to electronic ignition.
But you need the cylinder head, cam pulley, inlet manifold and gearchange linkage as well as the complete CDI setup and wiring loom to do it...

Now I need that head gasket....