Nippy 3 bearing engines

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…)

Chris Gould has seen one of these engines before. There is a groove in the crank web and the flat plate covers it instead of having the aluminium castings like the earlier engines. They have 1 5/16″ big ends. The con rods are the same as Ulster ones with an 1/8″ machined off one side of the big ends. There is a danger that the drillings in the webs can be exposed when the crank pins are reground. The normal Ruby crankcase was used, probably without the oil jet drillings. Packing pieces were used under the mounting feet to tilt it to the sports angle. According to some of the parts lists it had the roller centre camshaft bearing, but he surmised that this was just a printing error. Ian Williams confirms this; a Nippy profile 3 bearing engine camshaft in his ownership has a plain centre bearing.

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.

One owner of a late Nippy that could have had a sports 3 bearing originally noted that as his – quite original – car had a 5.25 axle so it may have originally had a standard engine, not a pressurised one. He commented:
“I have only ever seen one sports  3 bearing engine which Dave Wilkinson had at 750 Beaulieu years ago. He had got it from Wayne Rushton and was asking £6k for it so I didn’t take up his offer of removing the sump to
have a look at the internals”.

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?

Ian Williams’ photos below:
Left is a three bearing Nippy, note the plain centre bearing and high lift lobes.
Middle is a Normal Nippy roller bearing and high lift lobes.
Right is a Standard cam for comparison – notice roller centre, low lift lobes and much smaller front bearing.
Both the Nippy cams use a special front bearing and timing gear.
If you study closely the for sale engine at the top of the post, it is possible to see it has a plain centre bearing and high lift lobes, the flanks of which are concave and visible in the pictures:
other information; old ebay ad text
Rare item! Austin Seven sports model pressure fed crank and rods for three bearing engine incl. centre bearing shells – as fitted to late model Nippy/Speedy cars. This is different from the standard three bearing crankshaft and rods – see photos. Oil feed to big ends is pressure fed via centre main – not “spit and hope” as on standard Sevens. I believe it will fit a standard three bearing crankcase with modifications to the oil feed arrangements to bring it up to sports “spec” but I can’t provide details.

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