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

[Big D]

More photos.

[Big D]

Hi all,

I’ve been tied up working on some other projects so it’s been a while since my last update.

My brake guy has hopefully worked out a solution for me. You might recall in his testing he couldn’t fault one of the wheel cylinders I sent him but believed the other one was leaking between the cylinder and the sleeve. He has changed tack a bit and now believes some different cups will do the job. He supplied me with 12 x English made cups and 12 x Spanish made cups. These are about 1.5mm shorter than the Japanese cups (still good quality he thinks) I was using with the new kits. He fitted these in the two cylinders and had been testing them on the bench at 100psi with no leaks. They are noticeably freer in the cylinder bores than the other cups. I have now replaced all the original pistons and cups with these new pistons, springs and full cups. I’ve made a note that I’ve fitted the English made cups on the driver’s side of the vehicle and the Spanish made ones on the other side. I bled the brakes using the pressure bleeder and I will monitor the wheel cylinders now for leaks. I have my fingers crossed!

After bleeding the brakes, I moved the M8 under its own power in the workshop for the first time today. That was quite a feeling but the elation quickly disappeared when I realised I have some tweaking to do and need to sort a number of things out.

The transfer case linkages are not right as I could only select low range today and got no movement in high range. I also couldn’t engage the front axle using the lever. Hopefully it is not an interlock problem in the transfer case but I’m more inclined to think I have the lengths of both fabricated control rods wrong so I will need to adjust those.

I’m also not sure about the gearshift lever. I mentioned this some time ago that I had two different shaped gearstick levers, and both appeared to be originals. I had fitted the one that seemed to be a better shape but it really limits where you can have your legs without clashing with the gearstick lever and the steering wheel. I am going to try the other one which has a lower profile when in the forward position (reverse/first gear).

I’d have to say to that having never driven one of these vehicles before, they appear best suited to someone smaller than me! I am 184cm and 93kg (6 ½” and 204 pounds) and it feels a real tight fit in that driver’s area. It seems there is little room between the left side of the steering wheel and the side of the hull and the right side of the steering wheel and the gearstick. It also feels like you’ve just about got your knees up around your ears when you have your feet on the pedals. I think the fact that my body is well over 50 years of age doesn’t help either! LOL. What are others’ experiences? A slightly smaller diameter steering wheel would help I feel.

Thanks to Brian for supplying me some working ammeters. I’m not quite sure what I changed with the shunt wiring but after some experimentation, I now have a working ammeter in the instrument panel.

That is all for today…

[Big D]

More photos.

[Bob Carriere]

....... similar to the CMP cab 11 Blues............. designed for depression raised teenagers who were 5'5" and 135 pounds with size 8 boots .....brave little fellas they were!!!!!!!

Bob C.

[Big D]

Hi Bob,

Yes, it wasn't something I considered when I bought the beast. Haha. I'm told that some people just sit on a blanket rather than a cushion which would lower one a bit and help with the legroom. I might give that a try.

[Lynn Eades]

Darryl, If you continue to have trouble with the brakes leaking, you could add a 3 psi residual line pressure valve. It will hold a low pressure in the lines, which will help to keep the cup lips against the bores. It will not make your brakes drag as the return springs should be enough to overcome the pressure. There is possibly a line pressure valve in the bottom of the m/c, already, but an inline one will have a higher pressure.
Were the cylinders originally fitted with cup expanders? A number of old Dodge wheel cylinders that I've opened up, had them.
What might be involved in altering the angle of the steering column? I see the dash panel is a limitation. How is the box mounted?

[Big D]

Hi Lynn,

Thanks for the reply. I don't want to speak too soon but I have yet to see any leakage from the wheel cylinders. I have my fingers crossed....

As far as the ergonomics go, I have been reminded that the armoured floor I have in the front is a bit higher than the original floor. That wouldn't help.

The foot pedal placement will also take some getting used to. I wonder how low the clutch and brake levers supposed to be with respect to the floor or throttle pedal. It seems that you have to lift your legs quite high off the floor to even operate the pedals, which gives the 'knees around the ears' feeling.

I adjusted both pedals today at the back of the master cylinders and this dropped the pedals a bit. I couldn't get as much adjustment out of the clutch adjuster though. I did wonder about putting in a thick strip of steel to act as a packer between the mounting points on the clutch and brake pedal assembly and the hull using some longer bolts. This would have the effect of directly lowering the pedals which would also help. I don't think there is much wiggle room with moving the steering box.

I will keep tinkering!