1 5/16 shell bearings

[Steve Clare]

Why doesn't anyone make 1 5/16 rods with shell bearings to fit a phoenix crank ?

[David Cochrane]

Because you would probably have to commission hundreds of them to make it viable. And the demand for that quantity simply isn't there! Are you volunteering?

[Steve Clare]

Unfortunately I don't have the means or the skills required. (Or come to think of it the inclination).
I asked the question in case someone said- 'yes they are available' , or conversely 'because they wouldn't work on a 2 bearing crank'.

[Steve Clare]

So no comments on the viability/ availability of shell bearing con rods for 1 5/16" 2 bearing cranks?

[Howard Wright]

Hi Steve

I note your puzzlement at the lack of response so here are my comments for what they are worth (I’m no expert by the way).

On a 1 5/16 two bearing crank some whip is expected and white metal bearings can be scraped to relieve the edges and allow the whip not to be constrained. Shell bearings tend to be a constant diameter, slightly harder and would provide a hard edge to any whipping which may expedite failure of the bearing or crank!!

White metal on an Austin rod is relatively thin, replacing it with a shell bearing would entail boring out the aperture and weakening the rod.

I have a 1 1/2” crank in my special with Nippy rods and white metal bearings. If (I hope not soon) they wear out I will probably change to Hadley rods with Renault 4 bearings. There is much much less whip with a 1 1/2” crank. If you are determined to use shell bearings a 1 1/2” crank is probably the way to go. It does fit in a standard crankcase with some fettling!

I’ll leave it to the experts to comment if my views are right or wrong!

Cheers

Howard

[Colin Wilks]

I too was waiting for an expert response to this one, but I think shells would not perform as well as white metal in a splash fed engine, where the flow of oil through the big end, which means it has to get in and out easily, would be less. Be interesting to know why you want shells, and what benefit you expect from them. Pressure fed engines are a different world beyond my ken.

[Stuart Giles]

So no comments on the viability/ availability of shell bearing con rods for 1 5/16" 2 bearing cranks?

That's probably because most shell bearing conversions start with a suitable 'off the peg' shell bearing and work the crank journals and rods around that. The shell bearings used on the 1 1/2" Phoenix etc cranks are standard fitment on  Renault "Billancourt" motors including the (non TL) 4 and 6 cars. The journal diameter is actually 38mm which is a few thou short of 1 1/2" obviously the cranks are machined to suit.

Would be perfectly possible to do something similar for a specially machined Phoenix forging using an 'off the peg' shell from a motorbike or such, but the crank would almost certainly need to be machined with much narrower journals to suit the available bearing shell as modern bearing materials are such that you aren't likely find any shells of somewhere near a nominal 1 5/16" journal that comes close to the metalled A7 bearing width. Having said all that, it would be simpler (and almost certainly cheaper) to just use a new splash fed 1 1/2" crank and rods which are available "off the shelf"

Lots of vintage motors have had this kind of stuff done, so often don't look quite so vintage on the inside. Here's one I prepared earlier.



20's Chevrolet crank I had made to take early Ford shell bearing conrods; the narrower big journals are clearly visible.

[Steve Clare]

Thanks for these informative replies.
I had simply thought that shell bearings would be easy to assemble, and replace, so more straightforward and probably cheaper than white metal.
It had crossed my mind that as I'm intending to commission some modern conrods which would pass down the bores, why not have them machined to take shell bearings to fit my 1 5/16 splash fed phoenix crank?
It seems however from your comments that this might risk the crank and rods due to whip.
It's all interesting stuff, but it sounds like white metal is the sensible option.
I like the Chevrolet crank, extremely nice. I ran a 1923 Chevy Superior for some years, which was a great car, exposed valve gear and wooden wheels with beaded edge tyres. Wandered around the road too much for comfort, but felt like it would chug clear across America without a glitch.
Thanks again for the replies