I have had an e-mail today from Bob Clare, the MMM Registrar, asking about gearbox product codes. Bob and I have discussed these in the past, but I have never found time to investigate.
Below is a photo of the gearbox in Bill Scholfield's J. The product code 51 and the ratio stamp 4/14 aren't J2 or any Triple-M so are they Morris?
I have absolutely no Minor gearbox product code data - can as many people as possible check out their boxes and post any stampings they find here? Then we might be able to deduce the Minor codes. Thanks in advance.
For reference, J gearboxes should have the serial number stamped on top of the casing just in front of the remote turret mounting and should also either have the product code 72 which went with engines up to 2500AJ or 117 which went with engines from 2501AJ. The numbers to the rear are the speedo drive ratio, which should be 8/14 for the J.
And here's an extract from an earlier VMR Magazine detailing piston markings. These A, B, C, etc. piston markings should not be confused with the engine number suffixes - A, B, C, etc., which I THINK refer to very small oversizes in original standard bores. And then there are the letters stamped on the top surface of the cylinder blocks by each bore.
"Down in New Zealand, Alex Dempster has been stripping down a SV engine which still retained its original standard pistons and was wondering about the marking son the piston crowns. Here is what the Morris Owner of June 1932 had to say on the subject:
Regarding the markings adopted for Morris pistons, the complete range of pistons comprises five groups, of which "A" is the nominal or standard size. The remainder are considered oversize and the increase in diameter between each group is 0.25 mm. They are designated B, C, D and E, the latter being obtainable only to special order.
Each group is then divided into twenty-four individual piston sized ranging from -13 to +10. These figures refer to hundredths of a millimeter, and not thousandth's of an inch as is commonly supposed. Consequently, the variation in diameter between two consecutive pistons is only 0.01 mm or rather less than half a thousandth of an inch. For example, size A-10 would indicate a standard 57 mm piston with a diameter equal to that of the bore minus 0.1 mm.
In selecting a piston at the works, the following example can be taken: The piston clearance (which incidentally, should always be measured at the skirt) for the Minor is 0.11 mm to 0.12 mm. Assuming that piston A-10 is fitted and as a result of wear the skirt clearance has increased to 0.18 mm, then the following deduction applies:
A-10 piston fitted
Skirt clearance 0.18 mm
Skirt clearance required 0.11 mm
Difference 0.07 mm
Therefore A-10 piston plus 0.07 mm equals A-3 piston needed. Naturally, it is impossible to accurately forecast the piston size which will be needed after reboring, since this is entirely dependent upon the size of the cylinder bore when cleaned up. Careful micrometer readings should be taken of each bore, when after deducting the requisite clearance, you will arrive at the piston size. The letter "P" on the piston crown indicates that the piston is of the Morris parallel type.”
Like Halbe I have found a six digit number below and to the left of the handbrake. The number is 185050. Also of significance are some digits arranged radially around the speedo drive exit hole. These are : 4 9 31, which I guess at first sight would refer to date of manufacture. If this is the case then my car would have had it's box replaced within 9 months of manufacture! Unless the digits refer to something else, which seems unlikely?
Good info so far - hopefully a picture will emerge - yes, any and all numbers on any boxes would be good.
There are also other numbers of potential interest - pareticularly those stamped on front axle beams which I'd like to investigate - if anyone has any numbers from front axles, please feel free to start a new thread!
Can't find any 3 speed stamped No. except the 19050 with M C Ltd underneath, these are cast on the side and appear to be part No.s and are not on what appears to be a hornet box which has the filler in a different position on the side bulge and a web under the rear which is not on the minor boxes. Also is a date code like Mikes for '32. 4 speed boxes have stamped No.s;- 20370 and 11075, both with 10 stamped below and are in front of the turret. The 3 speeds dont have the space in front of the turret for a number
Bill got an answer from the WHSC Registrar, Ron Turner which makes interesting reading:
"Hi Bill
Your J2 gearbox is in fact a 1932 Wolseley Hornet gearbox.
The number 51 was the Sanction (or batch) number as manufactured by Wolseley in 1932
The number 201 was normally the Chassis number linking main components to it eg. the engine /gearbox/ axles.
Sanction 51 included car numbers 105001 to 105800
The number 201 was an early number in this batch which would have been manufactured at the end of 31 early 32.
The car would have been designated a Sports Hornet - not a Special.
The numbers 4/14 refer to the speedo gearing within the gearbox to accomodate the specific speedo as fitted to the vehicle - on this car a small 3" dia smiths gauge.
We are always looking to reunite components on to Hornets!!!!!!!!!!!!!!
Regards Ron Turner - Registrar Wolseley Hornet Special Club."
But let's not stop looking for numbers on our Minor boxes - let's see if we can gather sufficient data to be able to understand our numbers.
These numbers are from what I think is a Morris box ( 4-speed constant mesh) . In front of the turret 4516 over 74. Behind the turret 4 over 17. These are stamps, but on the casing there are cast-in numbers - 4768 over 187383D
I have just acquired the correct gearbox for my Jensen a 1933 non syncro four speed box with the following numbers:- Serial No 50(3 or 5)9 , Type No 74, Speedo gears 4/17. On first inspection it appears in good order, little wear on the input splines.
the numbers on my gearbox 1133 over 110, in front of gear lever and 4over 17 behind gear lever hope this helps Colin