Here are pictures of an engine 262214 currently for sale in August 2017:
The 3 bearing crankshaft came in at engine number 249052 Engine number, chassis 247765.
The 3 bearing crank on Sports models arrived at chassis 257842. (so presumably, that means 3 bearing Sports engines would have been nearly 260000…)
One owner, comparing the picture with his pressure-fed Speedy engine:
It appears that the oil supply to the crank is through the central bearing rather than from the front of the crankshaft, as in the Speedy type crank. But the question arises, how does the oil get from the centre bearing to the big ends 2 and 3? I wonder what is under those plates on the crank webs. The standard pressure fed crank has bolt on aluminium oil transfer channels. Maybe the webs have gouges which are covered by the plates to form channels The camshaft centre bearing is a shell bearing; is the camshaft standard? No pinch-bolts on the con-rods so I presume the gudgeon pins are of the floating type.
Another former Nippy owner recalls:
“The “standard” spit and hope engines appear completely as in one’s Ruby. I have only ever seen one such engine that I think was genuine, in the Windley’s scrapyard circa 1968. The car (steel, 1937) was utterly complete but so frightful that even I couldn’t contemplate a rebuild. I recall it had the sidedraught manifold. At that time, knowing little, I couldn’t believe the standard 3 bearing was original to the car. I knew Tommy Windley quite well (he had a 3 litre Bentley) and he went and got the logbook which seemed to confirm this. What I can’t say is whether the transmission line height was the same as a Ruby but I don’t think it could be that different. I do recall that someone had found two 3 bearing cases with different drive line heights”.
Other evidence (known engines) seem to suggest that:
1. the pressure fed 3 bearing is 1 5/16″ and smooth-sided, and the same as the standard non-pressure engine casting with the exception of no oil jet drillings/setscrews, and a larger aperture for the high lift camshaft.
2. one crankcase has been numbered 1A; one other is remembered as 9E…
3. [Nippy 3 bearing crank] is pressurised through centre main alone, not as per the Grasshopper spec article (end of this post) to front and middle.
There has been some discussion on the drivetrain height i.e. on some crankcases the feet being different. This could be a red herring, unless anything emerges to support.
Can anyone elucidate further, with evidence? Can you add more to the debate?