The Car Challenge

[Nereus]

Is it this particular engine (block) that is unique rather than this engine range?
Perhaps it was an engine that won the Mille Miglia or similar ?

Not just this particular engine. Won many races but not sure about Mille Miglia. Was not confirned to race tracks.

[Nereus]

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[Frank Hovis]

Is the black thing at the front of the camshaft important? Is it some sort of dry sump mechanism?

[Nereus]

Is the black thing at the front of the camshaft important? Is it some sort of dry sump mechanism?

Not sure what "black thing" you are referring to? All the "bits" are important, but nothing to do with a dry sump.

[Frank Hovis]

The black thing, is the housing round what Steve G identified as a shaft drive for the camshaft, I can't imagine it needs a big housing like that if it's only for a shaft which I why I've been looking for a secondary purpose for it.
Nothing else about the engine looks particularly odd.

[Nereus]

The black thing, is the housing round what Steve G identified as a shaft drive for the camshaft, I can't imagine it needs a big housing like that if it's only for a shaft which I why I've been looking for a secondary purpose for it.
Nothing else about the engine looks particularly odd.

If you are referring to the "black thing" behind the big white disc yes, it does have another purpose! But you asked about the black thing in front of the cam shaft, which is on top of the cylinder head. (as with the white disc, disregard the odd device that is sticking up near the rear end of the camshaft, it is just a dial guage and magnetic mounting arm they are using to make adjustments during a rebuild).

[Frank Hovis]

Sorry for the confusion - the black thing was always the black thing between, presumably, the crankshaft and the camshaft, housing the camshaft drive shaft.

You must've thought I was mad that some spindly tools and a gauge and whatever else is up there could be mistaken for an alternator, supercharger or dry sump pump.

[STEVE G]

I think the odd thing about this is that it's way too small for an average 1930's racing car, most of them were huge things, 6 litre V12's and larger. I know that they also had 500cc car racing but I think they were powered by two stroke motorbike engines which this isn't.

[Ginjaninja]

I think the odd thing about this is that it's way too small for an average 1930's racing car, most of them were huge things, 6 litre V12's and larger. I know that they also had 500cc car racing but I think they were powered by two stroke motorbike engines which this isn't.

Caterham comes to mind hence the shaft-driven rear wheel drive.
??
GN.

[Frank Hovis]

The black thing is the distributor ?

[STEVE G]

The black thing is the distributor ?

That's what I think it is.

[Frank Hovis]

Black "thing" is not a starter motor. Alternators were not invented at that time.

Missed the cheeky wink, the black thing is the dynamo.

But that's hardly unique, unless having it 'powered up' using the camshaft driveshaft is a unique feature?

[Nereus]

Black "thing" is not a starter motor. Alternators were not invented at that time.

Missed the cheeky wink, the black thing is the dynamo.
But that's hardly unique, unless having it 'powered up' using the camshaft driveshaft is a unique feature?

Past my bedtime, but yes it is a dynamo. But you have it arse about, the drive to the OHC is via the dynamo. There are a couple of other things about it, but I will finish it tomorrow.

[Frank Hovis]

A google of "Dynamo driving the camshaft" bears fruit at http://www.mgmmm.com/Yearbook%20article ... amo-BF.pdf

Suggesting an MG (or possibly a Morris Minor).

[Nereus]

Yes MG. I am a bit surprised nobody picked this up before. The Mark is a British icon to this day!

The engines were developed by Morris Motors from the Wolseley engines in the early 30`s under the direction of Frank Woollard and Cecil Kimber. The engine factory was in Coventry, and later Courthouse Green. The early units were 848 cc and had a 2-bearing crankshaft, which soon became notorious for breaking. They were further developed to incorporate a 3 bearing crank and 887 cc capacity. In their original basic factory form they produced around 27 hp at 4,500 rpm.

The vertical drive via the dynamo is what is unique. It has not been used in any other engine design before or since. Properly set up it was an extremely accurate and reliable drive. The link Frank has posted shows some of it. A bevel gear drive from the front of the crankshaft, through the extended armature shaft of the dynamo, a coupling via a disc that had some flex in it, a second right angle set of bevel gears mounted at the front of the cylinder head which drove the cam shaft.

The cylinder head was a “cross flow” design, also advanced for its time. The valve rocker arms where mounted on stationary shafts down each side of the head.
The camshaft ran in bearings down the centre and directly over the rocker arms. Again in this arrangement an ingenious method was used to adjust the valve “lash” or clearance. The rocker arms moved on a split eccentric bronze bush. To adjust the clearance the tension on a clamp was released and the bush, which had a hexagon shape on one end, was turned in it’s housing, which altered the clearance.

The 4 cylinder engine shown here was produced in what was then large numbers. They were used in all of the M and J Types, PA, PB, K, TA and several other types up until production stopped with the advent of WW2.

In 1933 they added a 6 cylinder engine of 1086 cc capacity. This engine was identical except for the additional 2 cylinders. It was used in both an F type and L type, plus in later years various racing models such as the K type. Later versions were increased to 1271 cc.

And the reason I have rambled on so much about these engines is that the first car I ever had, before I had a driving licence, was an MG L1. These are very rare cars today as only 486 were ever built in a couple of different body styles. I have tried for years to trace this car and it now appears that it MAY have survived and in a restored condition in Australia.

And for interest a note about the dynamo. All of them were of a “third brush” design. They had no voltage regulator, just a reverse current “cut out”. The voltage could be adjusted by moving the “third brush”. This had to be set depending a bit on the use of the car, and how much electrical load was on it. Set too high and you would cook the battery, too low and you would end up with a flat battery!

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