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

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More photos.

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Hi all,

Here are a few photos of what I’ve been doing on the M8 over the last few weeks.

After I completed the handbrake assembly and got that working well, I fitted the gear-change housing and rods and then the intermediate floor. I’m not 100% sure I won’t have this floor piece out again but it will make a nice change to be working over the top of something relatively flat. The body was taking a beating climbing over and over the transfer case and that large cross member that holds it.

I’ve also fitted all the drive-shafts with the exception of the main one from the gearbox (obviously) and the one to the intermediate axle. I have left one side of the transfer case protective shield off as it is too difficult to get at everything under there with that in place. As I say, some of these parts may have to come out again at some point if things aren’t quite right, but it has been a good exercise seeing if everything is fitting correctly and working. It also ensures I have everything I need now, rather than finding out later on that I am missing something. I had to buy a bunch of driveshaft universal points and bearing caps (thanks Ross) and even while I was fitting them I realised I got my count wrong and needed another four bearing caps!

I have continued the work on the 37mm shells for the turret and sponson rack using the stencils from Van at Questmasters. I’d have to say it can be fiddly work but the results are worth it. I may not have the yellow quite right on the M63 shell projectiles, but I’m very happy with the results.

I’ve been sorting out the pieces for the clutch assembly. I have a new clutch release bearing coming (Aetna A-2526). The clutch pressure plate seems fine, and will just need a clean. I have a couple of discs and a new facing so will have to do something with those. The flywheel ring gear is a bit worn. Can this be flipped 180 degrees and put back on like other Hercules engines? Judging by the looks of the tooth pattern on the ring gear, I’m not sure… Has anyone tried this?

I’ve also been working out what I have in the way of an exhaust system. According to the parts manual, I have the early model exhaust muffler for a later model hull setup, but I will make the muffler work.

I used some foam weather strip to the radiator as cushioning for when it is fitted in the hull and I need to get some thinner stuff now to go between the radiator and the fan shrouds.

A shovel and pick were the last things on the restoration list week and they are done and ready to fit.

That’s all for this week.

[Big D]

More photos.

[Big D]

Hi all,

In between odd jobs on the M8, over the last couple of weeks a friend and I have been working on the Hercules engines for my scout car and the M8. It was a good chance to look at the differences between the scout car and M8 clutches which might assist other rebuilders.

I’ve attached a picture of an M8 pressure plate on the left and a Scout Car pressure plate on the right. The M8 pressure plate assembly is 355mm in outer diameter and the scout car clutch pressure plate assembly is 370mm in outer diameter to match the bigger flywheel. Of interest is that the face plates within the two pressure plates are the same dimensions.

The other point of interest is the two clutch plates pictured in photo 2. The one on the left is for an M8 and the one on the right is from a Scout Car. The overall diameter of these clutch plates are the same. The spline configuration and sizing appears to be the same and in fact, I think the hubs are exactly the same. However, the splined sleeve is fitted in opposite ways on the hubs between the scout car clutch plate and the M8 clutch plate. Photos 3 and 4 show the Scout car pressure plate and clutch disc on the left and the M8 pressure plate (the one in primer paint) and clutch disc on the right, so you can see the differences.

This could be of interest if you are after new fibre facings for your M8 or scout car. I’ve seen some dealers advertising M8 fibre linings and some advertising Scout car linings and from what I can see, the fibre facings will interchange. In addition, a complete M8/M20 clutch disc should work on a scout car and vice versa, providing the splined sleeve is positioned in the right way in the hub when the fibre linings are fitted.

Not sure how widely all this was known but hopefully a bit of handy information for M8/M20 and scout car engine rebuilders.

We have halfway built a fuel tank for the M8. In the end, I went for alloy construction, based on the advice I got from my fuel tank guru. It is 800mm wide, 460 mm high and 200mm wide, giving a volume of about 73 litres, which will be plenty for the use this M8 will get. The alloy construction is strong. I have a new fuel sender (thanks Kenet) and matching fuel gauge (thanks Charles) coming to set it all up. I anticipate strapping the tank to the cross section steel at the front of the engine bay, but will post photos once I’ve done this.

I’ve been putting off making up the hydraulic bleed junction I had been talking about. Not sure why, but it just went into the too hard basket for a while. I’d seen someone else make up one of these and I thought it was a great idea for improved access to all bleed points. Anyway, I thrashed out version 1 over the last couple of days. It is a block of alloy, drilled for the three hydraulic lines. I tapped all the holes for 1/8” NPT fittings. On the input side, I have NPT fittings coming which are female threaded at the inputs for standard tube nuts. On the other side, I have fitted NPT female adaptors for the bleed nipples. Finding the right fittings was a big part of the battle and I figured NPT threads were the best way to go. A bit of thread sealant on all the threads should do the trick. As I say, I don’t have the female adaptors for the tube nuts here yet, but you should get an idea of how it will work. I will mount the block on a sticky paid for starters and providing it all works, I’ll glue it in place.

Can anyone suggest a modern equivalent for the spring clips for the .30 cal spare barrel? I have drilled out the old broken bolts but now need to replace the clips.

Other things I’ve been working on are fitting some WW2 stamped jerry can mounts to the rear of the vehicle, gluing some felt strips on the radiator, and overhauling the carburettor.

By the way, the Hardy/Spicer FK35GB83 universal joint is a perfect match for the smaller propeller shafts on this.

That’s all for this week.

[Big D]

More photos.

[Big D]

Hi all,

Most of my time these last couple of weeks has been in tidying up odd jobs like rebuilding the carburettor and water pump. Both are ready to fit now but I will need to give the water pump a coat of the correct grey paint. I ran out so I’ve used some other grey paint in the meantime. There are some differences between the water pumps for the scout car and the M8 as you scout car guys can probably see.

I have also made a start on the gearbox rebuild. I had been putting off stripping it until I knew parts were on the way, but they should be here in a few weeks time. The gearbox seemed to come apart reasonably easily but as soon as I started stripping it I noticed that there were a couple of very small needle rollers in the bottom of the case. I figured one of the shafts was going to have some problems but it appears now that I have everything out, these needle rollers are not from this gearbox. Phew!

The countershaft assembly looks like it will clean up nicely. There is a little bit of pitting on the gears here and there, but overall, not bad. I will replace the bearings at either end.

The mainshaft has some problems. As you can see, one of the synchro rings is broken and there is a fair bit of wear on both sets of rings. The synchro face area on third gear is also badly worn so the gear needs replacing. As I say, I have new parts coming to so while I’m waiting on those, I’ll be cleaning up the housing and making up some gaskets ready for re-assembly. I'll also fit new mainshaft bearings.

I finished off the bleeder block for the hydraulics in the engine bay. Let’s see if it leaks when I get the fluid in there!

That is all….

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I just realised I neglected to post these few photos last time.