Help/advice needed with Honda GC160 engine

[Spurry]

I have one of these engines fitted to my power washer. I understand many portable machines can utilise this motor too. Long story short. Started the washer and the motor seized solid after a couple of minutes. Oil level was fine.
Removed and stripped down the engine to find that the crankshaft had picked up on the crankcase bearing surface area. It is a four-stroke engine which depends for lubrication on oil being sloshed about by a small finger on the big-end shell. As the washer is used infrequently I guess the oil had all drained off the crank.
I have polished the crank with impregnated diamond tape (beloved of plumbers) and the evidence of pick-up is gone. I am not sure what to do with the crankcase though. There are no bearings only the line-bored cases.
Has anyone had to deal with such an instance, and could offer any advice?
Thanks
Pete

[hermetic]

Hi spurry, unusual failure on what is usually a very reliable engine, no reason you cannot bore it out and put a pb bush in it, providing there is enough meat there to support it. but look carefully, if there was sufficient oil in it, there is another problem, like a blocked oil hole, or some other reason for a seize up. is the engine very old or well used?

phil

[Spurry]

Thanks for the reply Phil. I think the motor dates from 2002, but I doubt it's been used more than a dozen times. It's spotless inside and out. Although the oil was quite clean and up to level, not sure when (if) it was changed.
I will have a good look round for any blocked holes or other cause, but am at a bit of a loss at the mo.
Pete

[Sid_Vicious]

From what I've seen poking around on the net, newer versions have ballbearings in the housing. How is the condition on the surfaces on the linebored bore? It should be possible to bore it up and put in a bushing of another metal. Some of the "experts" said to don't use sandpaper or like it on the crank but to use battery acid to dissolve the alu that have welded it self to the crank because of the heat.

[Spurry]

Appreciate the reply. Unfortunately I have already cleaned the crankshaft. There were only a couple of small spots of aluminium on the shaft which polished off quite easily. It's a bit difficult to be subjective on the crankcase, and it's very awkward to try and photograph.
Pete

[Sid_Vicious]

Then I would give a quick polish of the bores and put it back together and give it a try to see if it runs. If it does it will maybe drop a few drops of oil from the bearings but afterfilling will take care of that. If that doesn't work you must do something more drastic

[John Rudd]

Pete,
I've stripped and rebuilt a few of the 'clone'engines that have been attached to generators...
Usually these have been bearinged engines, with proper roller bearings for the mains....

I can only suggest going with the advice given.....but before you do....
1) check the bearing bore, make sure its clean, if it has an oil way make sure that is clear.
2) oil the crank journal, trial fit in both bores, makes sure it turns nicely...
3) re-assemble the engine, plenty of oil on the rotating parts as you go.
4) fill crankcase to level with new oil....

Now cross your fingers and hope it runs ( preferably longer than it did before..... )

Finally, good luck with it..

[Spurry]

All noted thanks. I think it's rather ironic that the 'genuine' Honda has plain bores for the crank, where the clones have proper bearings. 
Pete

[hermetic]

Hi Pete, most of the Briggs and the like engines have a bearing at the drive end and a bush at the  mag flywheel end, I must admit I did think the Honda were bearings all round, but as long as it is oiled, the bush should be ok. Let us know how you get on!
Phil

[awemawson]

The early Honda motorcycles (C90 etc) had the mains running in the crank case - we laughed and expected them to fall over in short order, but they didn't.

It's ok I suppose if the pressure die casting is made from a suitable material 

[Spurry]

It's the mag/flywheel end that had the problem. It's all a bit strange as that side has (IIRC) 5 great holes to give access to the sloshing oil, whereas the drive side has one small hole....but it does have the timing belt whizzing along just next to it, so that must help.

Interesting point about the C90, nearest I got was a Chaly (for my wife) I hasten to add. Never gave an ounce of a problem during the time we had it. Our daughter used to love riding round the lawn on it. ( I steered as she was only about 18months old. )
Pete