Hi, an update:
It's actually a 1 5/16" splash feed engine, lightly tuned. I've extracted the crank and cleaned it up. The marks were due to corrosion, which is evident to a lesser degree on some of the other journals and has effectively written off the camshaft (severely rusted around all the bearings, particularly the centre). The crank looks much better after cleaning (sorry, don't have a photo at present); it is hardened and I would use it but my friend is considering the options:
1) New crank and new metalled rods
2) New crank and new shell rods
3) New crank, re-metalled Austin rods
4) Regrind existing crank, new shell or metalled rods
5) Regrind existing crank, re-metalled Austin rods
6) Leave existing crank alone, use re-metalled Austin rods, crack test them first
7) Leave existing crank alone, use a set of 2nd hand, standard Austin rods, crack test them and then scrape them in to fit
Now, me personally, I'd go with option 7) or possibly 6) but that's with fifty years of experience and access to the BA7C spares shed collection of rods, quite apart from being a cheapskate! The rods that were in the engine are sadly U/S with badly oversize little end holes.
I don't have good feelings about using modern, thin-flashed shells on a splash crank that is subject to whip but can anybody comment? I've used thick, white metal shells on a three bearing engine but that was eons ago
Which option would you choose?
It's actually a 1 5/16" splash feed engine, lightly tuned. I've extracted the crank and cleaned it up. The marks were due to corrosion, which is evident to a lesser degree on some of the other journals and has effectively written off the camshaft (severely rusted around all the bearings, particularly the centre). The crank looks much better after cleaning (sorry, don't have a photo at present); it is hardened and I would use it but my friend is considering the options:
1) New crank and new metalled rods
2) New crank and new shell rods
3) New crank, re-metalled Austin rods
4) Regrind existing crank, new shell or metalled rods
5) Regrind existing crank, re-metalled Austin rods
6) Leave existing crank alone, use re-metalled Austin rods, crack test them first
7) Leave existing crank alone, use a set of 2nd hand, standard Austin rods, crack test them and then scrape them in to fit
Now, me personally, I'd go with option 7) or possibly 6) but that's with fifty years of experience and access to the BA7C spares shed collection of rods, quite apart from being a cheapskate! The rods that were in the engine are sadly U/S with badly oversize little end holes.
I don't have good feelings about using modern, thin-flashed shells on a splash crank that is subject to whip but can anybody comment? I've used thick, white metal shells on a three bearing engine but that was eons ago
Which option would you choose?