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Now that I am driving this car more (and enjoying it) I have come across an issue with the brakes.

This is a right hand drive car which - as far as I can tell - was never fitted with power brakes. My concern is the physical effort needed on the pedal to bring the car to a stop.

Initial bite on the pedal is reasonably good, but much greater effort is needed on the pedal to bring the car to a stop.I'm left wondering at times whether I can pull it up if modern traffic slows in front of me. So far, so good. I realise it's a heavy car in the overall scheme of things, but light compared to some of the Packard models! Compounding that is that it's Ultramatic with no noticeable braking effect on the overrun.

Nevertheless, it does not feel right. I'm not inclined towards fitting a power booster (looks like a pretty big job). Here's a pic of the brake pedal, which at first glance looks a bit like the one used on power boosted setups, but there's no sign of a booster in the engine bay. Perhaps this was something concocted for the RHD cars?

I gather from the service manual that the standard brakes on these cars were designed to be "self energising", which I translate as a leading shoe design. This should reduce the effort at the pedal and provide good stopping power (when the car is moving forward).

I have not looked at the wheel cylinders or shoes yet, so don't know what shape these are in or what type of linings were fitted. It looks like the front brakes were overhauled about ten years ago and bonded linings fitted. (Service records fairly sketchy.)

The factory documentation prescribes riveted linings, but I'm inclined to go for softer bonded linings. This might improve the stopping power, and it has the advantage of no rivets to score the drums. Softer linings will presumably have a shorter life - not really an issue with tis car now.

I'm wondering whether the "brains trust" has experience with this setup and can suggest a way to improve it without major mods. I don't mind a fairly firm pedal and still have enough strength in the legs to give it a good shove!

Cheers Brian

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These were different from what we expect today, look for your booster under the floor/pedal area.

Search on the forum for "tredlevac" and you should find many stories.

Be cautious, from what I have read these fail without much warning.

From your symptoms, your brake booster is not functioning. With it functioning properly you should be able to lock up the wheels with not much more than toe pressure on the pedal. Without it, a LOT of effort is required. Given the alterations you note to your vacuum system, the first check would be to see if the vacuum feed to the booster is intact and functional.

You might want to checkout this link:packardinfo.com/xoops/html/modules/newbb ... um=4&post_id=183233#forumpost183233

If you click on the picture it should clear up.
Wes

The pedal setup in your photo is definitely for power brakes, not manual. You will find a fairly small diameter pushrod going through the floor to the combination booster and master cylinder. If this booster is not receiving vacuum or has otherwise been disabled you will have to push like crazy.

The standard manual setup would have a large rectangular shank on the pedal and the pedal would be higher from the floor. Please do not make any other modifications till this question has been settled.

Guys, thanks for all the helpful advice - as usual.

Sounds like I need to look harder for the brake booster. No reason why it would not be fitted to a RHD car, given the location.

Yes, the symptoms certainly sound like a failed booster. This car lost the vacuum feed for the wipers when the oil pump was converted, and now has electric wipers. Does the vacuum feed for the brake booster come from there, or from a fitting in the inlet manifold?

I think - but am not certain - that the brakes were better before!

Cheers

Brian

Booster uses intake manifold vacuum taken from the base of the carburetor via a 1-way check valve and a reserve tank to allow some limited booster action after the engine is shut down.

This was just posted yesterday, maybe some help?
youtube.com/watch?v=MlQVMBUG1OA
Wes

Well, I have moved forward a little on this mystery.

Firstly, it appears that the vacuum supply for the brake booster comes from a fitting on the carburettor (thanks Owen-Dyneto). At least in theory, because the car now has a 4-barrel Edelbrock carby, which I imagine has a similar fitting. Further investigation needed. And perhaps a call to the previous owner, who fitted the carby.

Secondly, I can just spot the top of the master cylinder in front of the bulkhead (not enough room to crawl underneath). Sure looks like the top of a Treadlevac unit. See pic. Further investigation also needed.

Will get it up on a hoist to investigate properly.

Cheers

Brian

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Ok I have spoken with the previous owner and fossicked around behind the brake pedal. It definitely has the Treadlevac brake booster, but it's not mounted to the lower firewall as in all the other references I've found. See pic - you can just spot the rubber bellows protruding into the area behind the pedal. The actuating rod is offset behind the pedal to the left.

Removed the air cleaner housing to find a vacuum attachment on the back of the Edelbrock carby. This line leads to quite a large vacuum reservoir under the front guard, then to the Treadlevac.

The previous owner confirmed that he overhauled the complete braking system about 30(!) years ago, so I guess it's time to do it again! I'm assuming that the current problem means the vacuum system is inoperative. The whole system is clearly due for an overhaul. Order dispatched to Kanters for the necessary bits.

Here's a pic of the setup behind the brake pedal. Quite odd. I assume (hope) the Treadlevac unit comes out that way.

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