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

[Big D]

More photos.

[T Creighton]

Hi Daryl,
You have overcome many problems along the way with your clever lines of thinking so I hesitate to offer this theory but it may be helpful (or not).

When the brake shoes are adjusted out to the drum, the cylinder cups will follow the shoe due to the spring between the two cups.
In a vertically mounted cylinder this could result in a cavity above the inlet port and below the uppermost cup that air could be trapped in from when the lines were first installed.
Being above the inlet port the air could remain trapped when bleeding the brakes.
If you were to slacken the shoe adjusters right back the shoe springs would draw the shoes back and move the cup down closer to the inlet to reduce the cavity and the risk of trapped air.
Then bleed the brakes.
Then re adjust the shoes out hard while holding some pressure on the pedal at the same time.
Then release the pedal and re adjust the shoes for clearance.
Best Regards, Terry.

[Big D]

Hi Terry

Great suggestion, thanks. Unfortunately we are one step ahead of you. My retired mechanic friend suggested exactly the same thing and I did that today prior to another round of bleeding. I neglected to put that in my update, sorry.

Any other ideas?

[maple_leaf_eh]

I just read through a number of recent posts, and smiled when you mentioned moving the M8 under its own power a few months ago. That is always a monumental occasion - like first flight in a repaired aircraft, or first shots downrange for a rebuilt rifle.

You are fortunate to have willing and equally clever businesses nearby who are helping you with parts and service. I could hear the voice of experience talking in the discussion of sleeved brake cylinders.

As for ergonomics, there is an acceptable modification in wartime Jeeps to notch the leftside wheel arch so the driver's seat can go back another 3-4". Otherwise, today's well fed enthusiasts wouldn't fit. Unfortunately the interior partitions of the M8 rule that out as an option. You might not have a choice except to change out the seat cushions for two thicknesses of folded wool blanket against a single thickness of curved seatback.

[Lynn Eades]

Darryl, have you disconnected the master cyl. and back bled it. Meaning using a pressure bleeder and pushing the fluid from the wheel cylinders back?

[Big D]

Hi Terry

Yes, it has often felt like two steps forward and one step back during this process.

I agree on the seat. A folded blanket maybe the best option to sit on. I have found though the fact that the steering wheel does come off nice and easy that removal is a good way to help one get in and out of the drivers seat reasonably quickly.

[Big D]

Hi Lynn,

No, reverse bleeding is something I had read about but I know little about it and I wasn’t sure how practical it was to actually do it. I guess I would need to do it at each Tee connection on each wheel but I figured by the time I did that on each wheel I might have introduced a whole lot of air anyway.

Any thoughts on how I’d go about it?

[Bruce Parker (RIP)]

Originally Posted by Big D

I agree on the seat. A folded blanket maybe the best option to sit on. I have found though the fact that the steering wheel does come off nice and easy that removal is a good way to help one get in and out of the drivers seat reasonably quickly.

The WW2 British Coventry armoured car required the driver remove the steering wheel to get into the driver's seat. The Fox only that you fold the back of the seat down and climb over it (I rarely fold it back upright and expect drivers in WW2 didn't either). So there is precedent...