andypugh

Aye, I know. My Ner-a-Car has one, which is what prompted the question.

Is that an artfully aged age-related plate? If so, it's well done.

I think I know who.

I had a motorcycle with a centrifugal oil cleaner, it looks like your cranks has the same feature, but rather by accident. I suspect that the build-up would never block the oilways, but would only collect in the blind bores under centrifugal force.

I am surprised you are not suggesting machining from solid with some extreme thread cutting on a Myford :-)

I have always found Lee Spring to be helpful. They advertise that they make custom springs. I got a wave spring from them, they insisted on sending a sample, and when I pointed out that I would only ever need one, they said that was fine. I assume from what you say that you have tried putting your parameters in their spring finder? https://www.leespring.co.uk/uk_compression_spec.asp?springType=C&subType=H&forWhat=Search You could consider buying oversize and grinding down on a mandrel.

I would have no qualms putting that back in to service. Not that I am any kind of expert. But, what fraction of the bearing surface is missing? 2%?

Probably post WW1, but I just saw this on a Youtube video: https://youtu.be/MbIlBZmZ4Xs?t=333

Cast iron crank-case? I was surprised by that, so far I have only seen (or noticed the material of) Aluminium (Dennis, for example) or Bronze (FIAT) crank-cases of that period.

It seems likely that it could be made, though one might expect it to decompose again (200C, again according to Wikipedia) https://en.wikipedia.org/wiki/Phosgene And that would lead to the emission of CO and Cl, neither of which are particularly good for you either. Though all three gasses probably beat being on fire.

I think it's worse than that, the gas created is Phosgene. Though Wikipedia suggests that the direct toxicity (to the liver) is just as bad, and it's an ozone-depleting gas too.

All authentic features of a WW1 truck 🙂

My own opinion (and it is worth exactly what you paid for it) would be that if you have the early pistons then they should be kept precisely because of that. I doubt that oil consumption is a significant expense in the context in which you will be operating the vehicle.

I think that it is normal for the ring lands to taper a few thou (in steps). The area above the top ring runs a lot hotter than the skirt.

I am guessing it is too complete and not enough of a challenge for your team?