Replacement Engine project

[peteracs]

Had a call from Jon at Stanwood to say all done on the parts he still had which was a shock given how long it took to get the block sorted. I collected the parts today.

First up was the head which he has skimmed, apparently he took 10 thou off to clear the imperfections. He also checked the clearance on the valve guides and volumes one of the chambers which came out at 53cc which is close to what I had measured originally. I need to now go back and revisit the piston dome volume to get a more accurate CR value.

Next was skimming the VX flywheel I obtained from Alan C and then sending it off with the crank and clutch cover for balancing. Jon does not do this, but uses a company in Sheffield (see photo of report, only some of which I can understand…).

He gave a crank a final polish for me and now I can get on with a dry build to confirm if the pistons need any modification re crown and valve cutouts. Then it is put all away until I can see when I am likely to need the engine, most likely 2026 at the rate we going!

Peter

[peteracs]

A while ago I bought some new pistons and rings for the engine (+0.40). When I originally measured the oil ring set (2 flat outer and the middle rippled one), I measured it at approx 5mm where the slot I bone piston was 4mm. I had thought for a while that the set, although correct part nos from Hastings, had incorrect oil rings.

Thinking I had to buy a new set, I revisited the rings today, partly to look at the oil ones and partly to see what the gap would be when installed. The gap was 15 thou on the upper two rings which is pretty much where GC was looking for according to his book. I also had a good look at the oil rings and realised my mistake. The middle ring has raised locating pieces to align the two outer rings and when you correctly assemble the three the size comes to just under 4mm which is exactly the spec by the piston manufacturer, so purchase avoided!

Peter