Humber Pig 31BK44, rear axle issue

[Hans]

My name is Hans and I live in The Netherlands. I recently bought a Humber Pig. It drives well, but only 1 rear wheel is driven. On the RH side the shaft between diff and wheel drive is in bits and pieces. Now I try to replace the original shaft for a modern version made from two homokinetics. De original part from the wheel hub and the part from the diff will be reused for this. At least, this is the plan.  Does anybody know whether this has been done before?

And are ther usefull tips to get the part out of the diff? The part from the hub was easy to get out.

My car data:

vehicle nr: 31BK44, FV1612A, chassis nr 33144

Thanks, Hans

[fv1609]

Hans welcome. It looks as if the damage was done some time ago & it is difficult to interpret everything from your photo when you bear in mind it should like this:

The damage may have been done by the driver moving off in 2nd gear putting too much strain on the rear joints. The preferred way is to move off in 1st gear which automatically spreads the load to the front axle as well.

The above joint is the Chobham joint fitted to the rear axle of armoured Humbers (Pig & Hornet) although it was considered stronger than the simpler Tracta joint fitted to the rear of unarmoured Humbers, it was less reliable. The problem was generally failure of the spring clip holding the articulating pads in place.

With respect I doubt that they could be rebuilt to original specification. It was a problem for the British Army in Northern Ireland who at one stage had 80 Pigs off the road with failures like yours. Their solution was to use the "weaker" Tracta joint fitted to the rear of unarmoured Humbers that had been scrapped & when they ran out of those re-manufactured them, this was not a long term solution until the Birfield joint was fitted to most of the so called Mk2 Pigs.

Your Pig was struck off census on 13/11/70 at BAOR which predates the up-armoured Pigs, the so called Mk2.

You refer to your Pig as a Mk2 & I'm afraid anyone looking at your Pig is likely to say that it is a Mk1 as it predates Mk2 that first started to appear in 1972.

I would be interested to see your chassis plate because I assume it states Mk 2 & probably was built under Contract No. 6/VEH/2755. I am sure you are 100% correct to call it Mk2.

The problem is that the Army failed to remember there were 20 Pig prototypes FV1609 built in 1956 that were designated Mk1. When Pig production got under way most plates just left the Mk blank, but some quite correctly were marked as Mk2.

When the up-armouring process came along the real Mk1 FV1609 had long since been forgotten and the current fleet of Pigs were incorrectly taken to be Mk1.

There is some coverage in this article:

https://hmvf.co.uk/topic/718-pig-in-a-poke/#comment-5957

 

[robin craig]

There is a guy in the south of England who just saved some Humber pig axles. I'm friends with him on Facebook and can make an introduction

 

[Hans]

5 hours ago, robin craig said:

There is a guy in the south of England who just saved some Humber pig axles. I'm friends with him on Facebook and can make an introduction

 

Hello Robin, I just just the FB group Humber Pig Humber 1 tom enth grou

[Hans]

If you can introduce me to him, I really apricate this, thanks, Hans

[Hans]

Goodmorning Clive, thanks for the reply. I have checked the chassis plate and found the following data:

contract nr: 6/VEH/27210

MK2

1953

Chassis nr: 33144

FV1612A

I tried to make a picture, but the plate is a a bad state, the figures are very hard to read.

I hope it helps, Hans

[Hans]

Clive, I managed to get some kind of readable picture of the chassisplate

[robin craig]

Hans do you want to buy the axles?

[Hans]

1 hour ago, robin craig said:

Hans do you want to buy the axles?

I just sent a personal message

[fv1609]

Hans yes thank you for the picture of the chassis plate & I agree with you that it certainly states that it is Mk 2. Although people who don't understand about the original Mk 1 FV1609 will say you have a Mk 1, but technically they are wrong & so were the Army in calling the up-armoured Pig Mk 2 when they should have called it the Mk 3.

I am suspicious of the 1953 date stamp, I think this is something a previous owner has done in the belief that it was made in 1953. There were no Pigs in 1953, your FV1612(A) was built around 1959 on what was an unarmoured CT Truck FV1602(A), when the chassis plate was changed from FV1602(A) to read FV1612(A)

Besides that as a FV1602(A) it entered service on 2/5/55 not 1953. Whoever stamped 1953 made a mess of it as '5' was placed out of line originally, I doubt that any workers in an ordnance factory would have done that.

But the critical thing is that Date marking if it is ever stamped should be on the first of those three spaces and dated when a repair has taken place. The date should line up with the column on the left that is marked Class of Repair. 

So the stamping of the year 1953 is wrong for several reasons.

It would be interesting to see the contract plate for the armoured body conversion which is directly below the passengers front window. It is about 3cm x 15cm it will give the contract number for this conversion & a serial number which may be prefixed by 'S' or 'ROF/N' or 'ROF/W'

 

 

 

[Hans]

Hello Clive,

here it is.

Very interesting to see some of the history of this vehicle, thanks!

[fv1609]

Hans thank you that is a nice clear picture. S 472 indicates the armoured body was supplied by Sankey. Note that the contract number for this conversion will differ from the contract number for the chassis supplied by Rootes.

I suspect that all chassis plates that refer to the Pig as Mk 2 were armoured conversions by Sankey. This is entirely logical as it was only Sankey who produced the Mk 1 which was designated FV1609.

The other two contractors for the Pig conversions were the Royal Ordnance Factories at Nottingham & Woolwich. The chassis plates for ROF conversion are of a slightly different layout that does not incorporate the Mk, but reserves a space for the Mk to be stamped in. I have never seen a ROF Pig with the Mk recorded.

As Wally has pointed out there were 3,700 Humber I ton vehicles. But of those 1,700 were converted to Pigs. I have never been able to establish how many were built by each of the three contractors, maybe Wally can put his finger on those figures?

The highest serial number I have seen for a Sankey is S 949.

[Hans]

All, a brief update on my rear axle problems. I managed to obtain a rear and front axle for my Humber Pig. However these axles are not in such a state that I can just swap them and start driving around. I need to disassemble them and make one usable rear axle out of two. Now the problem kicks in, I do not have any documentation how the rear axle is to be disassembled and re-assembled again. Is there a possibility to get some kind of documentation for this? Even a cut away drawing of the rear axle would be very helpful. If anybody can be of some help here? Many thanks, Hans

[fv1609]

Hans from what type of Humber did the donor rear axle come? There are 3 types of rear axle that will limit the degree of interchangeability.

Should be no problem with interchangeability on the front axle.

When changing the axles you'll need to slacken off the tension in the torsion bars before disconnecting them. You will need a set of strong "axle" stands to support the body as the full range of torsion adjustment can raise or lower each wheel station by nearly 12 inches.

[fv1609]

On 10/21/2023 at 6:50 AM, Hans said:

I do not have any documentation how the rear axle is to be disassembled and re-assembled again. Is there a possibility to get some kind of documentation for this? Even a cut away drawing of the rear axle would be very helpful. If anybody can be of some help here?

Yes I can help but I need to know which of the three types of rear axle joints that you have. Some photos should help to determine the type of axle you are proposing to use to rebuild your axle & if they are compatible.

[Hans]

Goodmorning Clive, thanks for the offered help so far. Currently I need to fix my other vehicle (Land Rover Lightweight) in order to have an MOT after changing the chassis. When this is finished, I can work again on the Humber. I will get back to you as soon as possible. Thanks, Hans

[fv1609]

Hans yes there are always so many things to do, I now only have one MV but jobs still pile up. I was afraid you had maybe given up on the Pig but glad that is not the case.