How To: Restoration of Ford M8 armoured car US Ordnance number 7373

[Big D]

Hi all,

I have now learnt (thanks to Willy) that the conduit that runs around the hull actually carries the 12 volt power supply for the terminal box on each sponson, as well as the CO213 cordage that links the BC606's for the commander and the loader. The conduit terminates at the terminal boxes and then there is a short length of cordage to each BC606. This fits with what I was seeing in the plans.

What I was confused about were photos of some restored M8’s that had the cordage on the firewall inside the hull connecting the commander’s and loaders BC606’s. I understand now that this is a post-war change. I’m going the wartime route with the conduit around the hull, providing I can get my hands on enough of the conduit!

I’ve now connected up the four BC606’s and the FT237 radio tray using the CO213 cordage. Preparing the cordage was a bit of a tedious job. Seperating the shield on the outside is time-consuming as it is very tightly wound around the internal wires.

I wired in the cordage for the driver and co-driver BC606’s in situ, only because I wanted to be sure of the lengths of the cable required. I wired the BC606’s for the commander and loader out of the vehicle and that was a darned sight easier. I’d have to say, that despite all the drawings and plans, without knowing exactly how it was all laid out, I still needed to do lots of research and have a good think about the layout and how it was connected both before and during the installation.

I was (and still am) a bit confused by the layout of the BC606’s. The plans show that the BC606’s for the driver, co-driver and commander should be positioned with the INT/RADIO switch and Volume Control side of the unit down. I setup the BC606’s for the driver and co-driver in this way as per the drawings.

I placed the loader’s BC606 as per the drawings with the INT/RADIO switch and Volume Control up. As I say, the drawings say that the Commander’s BC606 should be positioned with the INT/RADIO switch and Volume Control side down though, which didn’t make much sense to me.

What was the logic to how these BC606’s were fitted? I have seen numerous variations in the setups in restored M8’s, and a number of pictures of M8’s during wartime also showed variations. Why not keep them all in the same layout with the INT/RADIO switch and Volume Control upwards where the crewman can see it and change it if required?

In the end, I positioned the Commander’s unit with the INT/RADIO switch and Volume Control up, as per the Loader’s unit. I guess someone will correct me if it is wrong.

Along with the radio stuff, I’ve been trying to progress the gun. We haven’t been able to remove the two screws holding the recoil system in place. These screws have an allen type head on them but they were pretty knackered and corroded. I had been soaking the screws with penetrating oil for several months but the heads weren’t good enough to get a decent bite on them with the allen screw bit. We tried welding a bolt onto one screw but even then we couldn’t get the thing to budge. As a result, I will be taking it into a metal specialist next week to get the screws removed by spark erosion.

I got the boys in the engineering shop to profile cut a tool for removing the big nut on the barrel. This will allow me to remove the sleigh. Again, this nut is stuck and I’m better off having a tool that fits it properly before trying to lever it much more. l will give this tool a try next week and see if that will shift the nut.

[Big D]

More photos.

[Big D]

Hi all,

Here are a few more progress photos from the last couple of days.

All the radio wiring and conduit is in now, some albeit temporarily. I didn't have any pictures of this cabling before I started so these photos might be handy for anyone else doing this sort of restoration.

I haven’t connected the cordage to the BC606’s for the commander and loader yet. Once I have the radios and a battery in, I will check that the system is working with the BC606’s for the driver and co-driver before connecting the other two BC606’s. I don’t see any point in complicating things until I know I have wired it right.

The mounting of the conduit and piping holding the CO213 cordage is not finalised yet as you can see by the cable ties. You probably get the idea though. I could use some of the correct conduit clamps if anyone has any. My homemade ones just aren’t quite the right shape. I am still finalising the layout and there is a possibility I will have to move the cabling/conduit in the hull to get the firewall in, as that is a tight fit, and not something I am looking forward to fitting. I still have some routing of the wiring to tidy up but I think it is pretty close to how I want it.

The steering box and clutch and brake pedal assembly are next so that I can sort out the hydraulics and instrument panel wiring. I managed to make one pushrod that I needed for the master cylinders and I have the other one coming (thanks John).

[Big D]

More photos.

[James P]

And that my friend big D is one hell of a great job you are doing, I see you got the gun off. When is the big green box getting mounted on axles and tires ?

[Big D]

Hi James P,

Thanks for that. I have the front springs ready to bolt to the hull but I am awaiting the availability of a crane in the workshop to position the hull a bit better so that I can mount the springs and axles. We didn't really have the workshop set up properly when the hull was dropped off after painting so we'll organise this first.

The front axle just needs the hubs reassembled and the brake lines on it done before it can be bolted to the springs. The intermediate and rear axles still need some work before I can fit them.

So, timewise.....perhaps the next couple of months? Fingers crossed.

[Big D]

Hi all,

Here is what I’ve been busy with over the last few days.

I fabricated a couple of pieces for the pushrods for the brake and clutch master cylinders, so I’ve now been able to mount the clutch and brake pedal assembly. The pushrod pieces aren’t my best work but they will do until if/when I source some new ones. I have some NOS return springs coming (thanks Philippe). I took some extra photos of the clutch and brake pedal assembly as I didn’t have a lot of photos of the layout. It is quite heavy and I had to use wooden blocks to hold this up while I bolted it in place. It is really a two man job to bolt it in but there isn’t room for two people in there!

The handbrake is now mounted. The mounting holes required 3/8” UNC bolts which had me fooled for a while. Most of the other stuff is UNF. The sector gear on the handbrake was pretty corroded and is not great but we’ll see how it goes.

I’ve fitted the steering box. I’ve used a grease and oil slurry in the steering box rather than just straight oil. The vehicle will be sitting around a lot and it might help prevent leaks. It has been sitting for a while now with no leaks so I have my fingers crossed.

I’ve done some touching up of the various mounting bolts in the front of the hull with the modeller’s paint but I still need to do a bit more.

I also starting routing the wiring for the instrument panel. I forgot to take the circuit diagram with me so I haven’t got this right yet and still have some work to do on it the next time I am in the workshop.

Next will be sorting out the hydraulic lines. I note in the parts manual that there are two different versions of the layout for the fuel primer pump. The version described as the ‘old primer installation’ has a fuel line from the fuel filter to the primer pump and a line from the primer pump to the fuel pump. The ‘new primer installation’ seems to have a third line for an engine setup with a vacuum pump. The old layout seems like the most straightforward way to set up the primer pump. Has anyone got any other thoughts?

I need to join a couple of pieces of brass braided conduit. What method do you guys use for that? I’ve heard of copper sheet being used to join pieces. What about the brass fittings on the end of these bits of conduit? Are these ‘sweated on’ to the braided conduit?

Does anyone recognise the single conduit with the fitting on the end of it in the photo? I’m told it is M8/M20 but just not sure what it is for.

I’m working on the markings etc to paint on the vehicle so am looking for some advice on that. I am talking to a couple of suppliers of paint stencil kits so I get the correct sized stars etc. I want the vehicle to have the markings of the US 86th Cavalry Reconnaissance Squadron Mechanised, 6th Armored Division. Can any of the experts on here advise the correct unit numbering? Presumably something like ‘6 Δ 86C’? What about Company/Troop numbering?