power DRUM brakes...

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Mar 18, 2004 | 03:50 PM

pward76

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Elder User

Joined: Sep 2002

Posts: 622

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From: Urbandale, Iowa

power DRUM brakes...

Someday I will do discs, but my current parts truck has power drums, and my current driver doesn't. Sooo.....

I know I need the firewall bracket, the booster, and master cylinder - should I take the proportioning valve as well? Anything else?

(both are 69 F100)

Mar 18, 2004 | 06:21 PM

Laughing Gas

Joined: Oct 1999

Posts: 1,165

Likes: 3

From: central Alberta

As long as they're both drum setups, you shouldn't need anything else. Easy swap.

mike

Mar 18, 2004 | 07:52 PM

4x4Subaru

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Joined: Feb 2004

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I was told that the valve is different from manual drums to power drums.

The manual valve is only a block and the power one is an actual working proportioning valve.

Get the valve while you are there just in case.

Mar 22, 2004 | 01:56 PM

bigric

Fleet Mechanic

Joined: Aug 2001

Posts: 1,526

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From: Round Rock, TX

When I did the swap I just snagged the bracket, booster, and master cylinder. I seem to remember that the pushrod length had to be changed, but I forget.

Mar 23, 2004 | 10:43 AM

rebocardo

Post Fiend

Joined: Jun 2002

Posts: 13,873

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From: Atlanta GA

> The manual valve is only a block and the power one is an
> actual working proportioning valve.

My 1971 with four wheel (power) drum brakes has a central/equalizer valve. If you loose pressure in one brake circuit it cuts it off and uses the other circuit (back or front).

There is no proportion valve and your master cyl. should have the front and back circuits split 50/50 inside under the cover.

It probably has a wire attached to the valve, take that part of the harness and take the little red lamp that sits on the lower part of the dash near the brake release handle. It is suppose to light up when there is a brake failure.

Since master cyl are $18 and less at Autozone, I see no reason to use the old one unless it is fairly brand new or you need an extra core.

Mar 25, 2004 | 06:35 PM

Laughing Gas

Joined: Oct 1999

Posts: 1,165

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From: central Alberta

Not sure about that difference between power and manual distribution blocks but you should only need an actual proportioning valve with front discs.

mike

Mar 25, 2004 | 07:23 PM

roadgemF100

Freshman User

Joined: Dec 2003

Posts: 27

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There is NO difference between manual and power drum distribution blocks. When you convert to power drum brakes, all you need is the power booster and brackets. When you upgrade to discs, then you'll need the proportioning valve, since you now have uneven braking front-to-back, and it'll need to be balanced out, which is the proportioning valve's duty.

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Mar 25, 2004 | 07:47 PM

Phinxter

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Joined: Feb 2004

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From: Saratoga, NY

I don't own a truck in these years but I just got done doing this swap on my 77. Since nobody mentioned this be sure to grab the pedal and mounting bracket from the donor truck, they should be different. Manual pedals have a different leverage ratio than power, usually man has 5:1 and pwr 3:1. If you were to use the man pedal on a pwr setup your brakes would be very touchy, until you got used to them if it worked at all. I couldn't use the original pedal bracket because it only had 1 set of holes drilled in it for a manual pedal, the donor had 2 (a '79) meaning this bracket could be used for both, cant understand why Ford would take so long to make a 'universal' bracket, I also agree with leaving the valve alone, I didn't change mine it works just as good, except I dont have to push the pedal as hard, but for sure if you do upgrade to frt. disks you'll have to change it since disks need loads more pressure than drums.