I have some questions about adjusting the drum brakes on my 64 F600. All things seem to start with this:


The breaks on this gal are NEW.
Rear is a complete overhaul including new lines.
Brake shoe size is 15 X 5.



The front have new drums on them with the paper tag still attached! Front wheel cylinders, from the back, may not have been replaced. Lines between font cylinders were not changed.



Hydrovac age is unknown but it still is fully painted and not at all rusty. The master cylinder looked old until I opened it up and could easily see bare clean metal on the inside - no rust what so ever and what fluid was in there was clear - very likely also new. Add to that I found a new push rod boot under the front seat (I'll put it on someday.)

The day I bought the truck it barely had any brake pedal. About an inch from the floor I suddenly had brakes. At that time, visual inspection seeing new lines and cylinders on the rear I figured the brakes were just way out of adjustment. It wasn't till I got her home I discovered the master cylinder was empty. I filled her up, disconnected the brake line and bench bleed the master cylinder. Reconnected the brake line (bleeding the fitting during connection) I had a much better pedal but not as good as it should be.

Following the break bleeding procedure for hydroboost I bled the system - no air at the hydroboost, no air found at any wheel. Still pedal wasn't quite what it should be but the ol girl would put your nose on the windshield if you wanted to. Engine off, the pedal was down and hard about 3 inches from the floor which seems low to me. When running 1st brake was about the same as engine off but you could pump the pedal up to what I would expect as normal. I hauled a few loads, brakes were adequate but not stellar.

About this time I developed a bad rear wheel seal leak (90wt, different thread). I ripped that side apart and was delighted my initial guess about the rear brakes was correct - they had been overhauled. Shoes on that side had very little 90wt grime on them so I cleaned them up and put her back together. Putting her back together I initially adjusted the brakes on that side a bit snug and after a few loads - they would hold the truck on a slight incline. Brake adjustment. Pedal movement was the same as before doing the wheel seal.

I've readjusted the rear brakes to drag the drums like I did long ago in the military - both rears in the air, parking break off, out of gear, just tight enough to keep the wheel from spinning when the opposite wheel was spun but loose enough so rapidly spinning a wheel would cause the opposite side to rotate a few inches. Pedal movement is still the same.

Went to adjust the fronts - one side drags as expected but the other is not anywhere close to the drum and is freely spinning on the bearings. I looked at both fronts - no holes to adjust the front drum brakes! It doesn't pull left or right like one would expect so brakes on both fronts must be working (or not working). I've not yet pulled a front wheel or drum but since the paper tags are still attached to both front drums and all that money was spent in the rear I can't imagine at this point the fronts were not overhauled at the same time. At this point my low pedal problem is likely the one front wheel being way out of adjustment.

I can tell from the drum casting the font brakes are 15 inch diameter but can't tell you what the width is. Researching the Webb part number (64449F) the drums are 3 inch width. Part number for front drum is in pic above and also cast into the drum.

Without pulling the wheel/drum how are front brakes adjusted?

 

No idea, but that's a neat trick on rear brake shoe adjustment!

Those retracting springs look kinda smoked though. If I could find good NOS I'd want new ones just because.

 

The "2-cylinder" front brakes have an adjusting cam...you should see two spring loaded 'bolts' at 3 and 9 o'clock on the backing plate.
It's just a wag, but turning the bolts/pins clockwise should adjust the shoes tighter to the drum, hopefully they aren't stuck!
All this from staying at a Holiday Inn Express last year, but I hope it helps.