John & Nate,
If resurrecting moribund old Honda engines is holy, then I’m on my way to sainthood. Did you know this one was seized? Not badly, as it turned out, and only on one side.
The attached pix will show you what I found as I went along.
See that one spark plug hole has been stripped, drilled out for an insert, and that has been buggered so that no plug was in the hole – for quite a while judging by what I found inside.
The heads of the screws holding the alternator cover in place were long gone. At the point of the picture, I had cut a slot in the heads of two with a small cold chisel sized to fit the blade of one of my impact driver bits. That moved them. If it hadn’t, there was one more possible move before drilling them out.
Now, with a 14mm socket on the end of the crank, I am sure that the engine is stuck.
The head came off relatively easily as I have been anointing all the fasteners with PB Blaster for the past few days.
I cleaned the debris out of the stuck cyl/piston and covered it in a pool of PBB to soak overnight. This afternoon I placed a 1″ hardwood dowel atop the piston and gave it a short stroke with 2lb. brass hammer. Tapping alternately the top of one piston and then the other eventually began to move the piston and soon I had it free enough to pull the cyls. up off the pistons.
This was likely a newly-built engine on its first overbore – the bores are roughly 64.25 mm. and have no taper or ovaling. The pistons are straight and square too. But the machinist who did the boring did not leave sufficient piston/cyl. clearance – the pistons are larger than nominal spec – and the engine had a light seizure – or two. The next thing that happened was that whoever responded to the seizure got that plug cross-threaded and stripped – or perhaps the heat of seizure stuck the steel plug hard in the alloy head.
The man with the wrench is already pissed off. His brand-new engine has just puked and now he’s gone and made things even worse. Out comes the hand-held power drill and a heli-coil insert. And you can guess the rest. The poor beaten bastard just dropped his tools and walked away leaving that cyl. open to the atmosphere.
Every engine – every machine – tells me stories about it’s history. My work is kind of archaeology – digging into the past, interpreting the traces/evidence of those who have gone there before.
I’ve 3.5 hrs. in so far inc. researching best available prices for pistons/rings/pins, tensioner, cam chain, etc. The only set of NOS Honda pistons I could find in the US was fouth-over (last overbore) and with rings sourced from elsewhere would have been more $ than the set I have ordered from the place in the Netherlands I have used before with satisfaction. They also had the best combo price for the tensioner body/small roller and the big roller. But their cam chain was twice what I can get a good one for here. The parts were 219 Euros which is around $290. With shipping it’s about $320.
Existential Motorcycles TEL: 828-6839289 Web: http://www.existentialmotorcycles.com
Alexander, NC 28701