Repairs to the Candidi Provocatore Allard

Binky points out what looks like a piece of snapped steel carrot still in the hub

This weekend I whizzed up to Binky Towers to help make good the damage what we done to it in the Exeter Trial, namely replace the halfshafts. People in the know have told us to replace both shafts and not just the one that's broken. The theory is that the survivor is probably structurally compromised in some way and will fail before too long when subjected to the sort of stress we'll put it under. It's far better to get a pair, although I suppose we could have the unbroken one tested somehow.

The rear wheel was decidedly wonky

The Allard hadn't moved since it was put away when it came home from Ilsington so we gingerly pushed it out of Rob's packed workshop into the carport where it usually lives. This has been boxed in with scaffolding until recently to fit solar panels to the roof of their house. Once the car was in our operating theatre for the day, we jacked it up and removed the rear wheels.

And here's another for the Candidi Provocatores' Black Museum

Obviously, the offside one came off very easily. In fact we were concerned it might come off as we pushed the Allard out of its resting place. That's what a three quarter floating back axle means - there's nothing to keep the broken end of the halfshaft in the axle casing.

Fully floating axles, like the ones on trucks, have two big bearings at the outer end as well as bearings supporting the diff so the axle shaft only has to cope with the torque of the drive. Semi-floating axles as found in most car axles support just the diff on bearings so the diff is said to be floating. The axle shaft transmitting the power runs on bearings inboard of the hub so also has to bear the weight of the vehicle and any wheel wobble or skidding.

Three quarter floating axles like those on Ford V8s and Allards have the bearings in the hub, not behind it as on semi-floating types. The bearing housing takes the weight of the vehicle so the half shaft only has to bear with the torque and any wobbles or skids.

All we had to do was disconnect the brakes and speedo drive, undo the knuckle joint at the forward end of the torque tube, unbolt the dampers and springs and then remove the axle.

Removing the rear axle was relatively straightforward as none of the nuts and bolts were seized. There was then the opportunity to use some weird and wonderful special tools without which we would've been well and truly stuck.

First off was the hub puller for the nearside brake drum. This would have been required to remove the right brake drum had not the shaft broken. Because of the internal design of the diff, this side had to come off as well.

This is how a Ford axle hub puller works.

Next was the spring flattening device. This resembles an instrument of torture and pushes the inner ends of the spring shackles out so that chaps can remove the transverse spring from the rear axle casing.

It has specially shaped ends that locate against the shackles and once the tension of the spring removal is easy. Then it just takes your chumrade to whack it nonchalantly with a copper mallet and the spring shrugs off its instrument of torture and defiantly reveals how narrow it is when off the car.

Here you can see how different the spring looks when not under extension

One of the best sorts of copper mallet is a Thor hammer and it's a satisfying thing to swing. Binky's neighbour popped by with some feeler gauges (they're all good sorts where he lives) and also admired it. He said the actual company name behind the Thor copper mallet was the BBC, which stood for the British Belting Company. They made the old flat drivebelts for driving machinery in workshops and found that when old and worn out belts ones were rolled up tightly and fitted to a hammer shaft they made very good soft hammers. Sometimes they were made of thick leather to make what became known as a hide hammer but latterly copper became the preferred material.

This made me wonder if this explained the origin of "belting" something hard i.e. giving it a severe clout. If belt hammers provided a belting, did hide hammers give a good hiding?

And has anyone ever given a bearing a severe broadcasting to get it to move?

Answers on a postcard please.

I'd never worked on an axle of this design before. Here Binky has just cut the lockwire securing the nuts

Once we'd undone the nuts, the whole diff and axle shaft assembly could be withdrawn

Next we undid the nearside of the diff housing to reveal the diff with its nuts all lockwired in place. Once those were undone we could slide the diff and the long stump of the offside driveshaft out of the casing..  

No garden sheds were harmed in the dismantling of this axle although it looks like several were in destroyed in this picture. Mr Robinson-Collins is still under the influence of swinging his Thor hammer about

Fortunately, the inner ends had 18 teeth, which meant we could use the 1947 Ford Pilot halfshafts that Rob had sourced. The replacements need shortening by 3 inches to match the narrower Allard axle but Rob knows a chap who has a programme that can do this easily on a CNC lathe.

Here the surviving Allard half shaft compares to the standard Ford items.

Having achieved our objective for the weekend on the Saturday, I asked Binky if there was anything else I could help with on the morrow and the following morning he suggested we fit some Offenhauser cylinder heads that he happened to have handy.

This is the engine bay before

Of course, I said let's do it. It wasn't too difficult, either, although the nearside cylinder head needed some persuasion from our new best friend Thor.

This is the engine bay during (and pending tappet clearances to be checked while the manifold is off)

Here we have the standard heads and manifold. They'll come in for something else - have no doubt!

The Offy ally heads look fantastic and are ribbed for extra air cooling. I forgot to ask what compression ration they might give but the combustion chambers look smaller to me so we will probably get a bigger bang and blow after the suck and squeeze.

24 stud heads for a 24 stud block. Ford V8s with 21 studs aren't so sought after and performance parts don't fit 'em.

The twin carb manifold will need a shorter dynamo if the front carb is to fit but it's not actually a dynamo but an alternator, with a surprising amount of space inside. It should stand shortening without affecting its charging ability.

With a twin carb manifold the engine will look quite different

It will be very interesting to see what it runs like with all the goodies on it - and how the replacement halfshafts stand up to the withering torque the old warhorse will now have!