New Flywheel & pump eccentric

Just fitted the new STW second batch flywheel to my engine. The old MW flywheel was badly centred on the casting, was eccentric and wobbled. The new flywheel is in cast steel, 1" smaller diameter and 1lb heavier. It has a run out of 2 thou on the diameter & 10 thou wobble. Good enough I think!

Also just made & fitted a smaller throw water pump eccentric, as per Julia. Looking forward to seeing how it all performs in Pompey next weekend.
Tim

Have just fitted a new eccentric as per Julia's design and steamed the engine. No more bang, bang, bang just whoosh,whoosh,whoosh! when revved hard. I tried it at various pressures, mainly it used to bang at high pressure, and it's sweet as a nut. Well done Julia for solving this problem, I think the banging must have come from backpressure with the pump trying to push more water through than the clacks could cope with as it only happened when driving or reving fast. I've now turned my attention to getting my flywheel running true, it seems to me that the grubscrews want to push it one way and the cotter pin the other. I've drilled and tapped a couple of extra holes for grub screws opposite the existing ones and that has helped a lot ( its down to 1mm out of kilter now) the engine just gets better & better

Steve
Did you fit a spacer between the pump rod and the eccentric strap? I haven't yet, as I think it will work OK without it.
Tim

Just back from Portsmouth. Terrific time there. We had 3.5 MW/STW Burrells pulling 3-4 waggons around giving passenger rides.

The new flwheeel & ground crankshaft is a huge improvement. The new water pump eccentric puts much less strain on the engine, but I think I need to revisit the ball clearances. The titanium piston that I fitted last December (2/3 rds the weight of the steel version) allows the engine to tick over very slowly indeed.

Next outing Gunpowder Mills next w/e.

Tim

Hi Tim

Yes I fitted a 5mm spacer so the piston is at the bottom of the cylinder, this roughly corresponds to the amount of reduced travel.