Brake issue-how can this happen?

I bought a '40 plymouth touring sedan today, I was all set to drive it home since the guy said she drove fine for him - obviously not for me as you'll see.
I got about 4 miles out and the there was smoke coming from under the car so we pulled into a hardeys so the wife and kids could eat while I checked the problem, two "nice car pal" and a helpful gent who owned a '52 hudson later and the problem was the brakes were hanging up...the car had a high hard peddle with the brake lights stuck on and the driver's rear somewhat hot while the p***enger rear has really hot. The PO said he had the MC replaced with a reman, new rubber lines, rebuilt wheel cylinders and new shoes...and the "brake springs were fine" his mechnic told him{man, I question that since I aways toss in the hardware kit with any drums I do}.
So, I have to ask- how can the brake peddle be at full extention{rest position}, hard as heck to even try and push{I tried}, the brake lights are on since there was trapped pressure in the system and then 20min later after sitting in the parking lot the peddel had about 2" of travel before engaging the brakes and the brake lights were off now...oh, that 2" of free peddel travel wasn't there when I left with the car 4 miles earlier.
Bad residual check valve in the MC?...
After I figure this one out I'll worry about how to shift the car into 1st gear easily every time...she doesn't like to go from 3rd to 1st...or why she shudders only in 1st...

While the ride was short and troublesome, it was a blast!..can't wait to find a transport and get it hauled home

 

Sounds like the brake pedal isn't actually returning to the rest position as the return spring is bad, OR the retrofitted master cylinder is somewhat different and the pushrod needs to be adjusted somehow to compensate.

Basicly the return port in the master cylinder isn't getting uncovered and thus heat in the system expands the trapped brake fluid in the lines to the point that the brakes eventually activate.

When things cool the fluid contracts and lets the shoes pull back a bit and the wheels turn again.

 

What does it have for brakes? Sounds like self adjusting brakes installed backwards or it could be non self adjusting set up too tight. The brakes expand when hot which heats up and expands the fluid. Does it have cable parking brakes on the rear or a transmission brake?

 

After I figure this one out I'll worry about how to shift the car into 1st gear easily every time...she doesn't like to go from 3rd to 1st...or why she shudders only in 1st...

is this an original car? the way to easily shift into first every time is to be stopped or nearly stopped. once you get used to the car you may be able to shift from 2nd down to first while slowly rolling.

 

This. I'd put money on it.

 

THIS HAPPENED to me last year on my original 40 ford sedan . I don't know how the chrysler cars are set up, but on the old fords the pushrod linkage on the master cyl. is adjustable, there has to be a certain amount of freeplay in the pedal or the brakes will lock up when they get hot or warm. usually after a few miles of driving . after I adjusted the linkage for more freeplay I had no more issues with the brakes. check your shop manual for the correct freeplay. my symptoms were exactly like yours. hope this helps

 

most old transmissions that I know of are not synchronized in first gear. This means you have to be stopped before you down shift into first gear. don't try and shift into 1st unless you are stopped completely. this is pretty much how they were until mid 60's.

 

My guess is either the brakes are adjusted too tight, or the pedal pushrod is too long for the new master cylinder.

The right drum being hotter could be that drum is adjusted tighter, or maybe his ace mechanic got both the "trailing" shoes on that side.

Best of luck to you on fixing it.

 

Had a similar problem on an old 54 Merc I had.

Turned out to be the rear rubber brake hose from the body to the diff was perished inside and a "flap of rubber' on the inside of the hose was holding the pressure to the rear brakes.
Slowly the pressure would bleed off and the brakes would return to normal until the next time I pushed the pedal!!

Maybe have someone wiggle that hose while you depress the pedal. If the brakes release then thats the cause.

Not a common cause I know,but it happened to me!

 

If the brake lights are on, there is pressure in the system that can't release. The most
common cause, as mentioned, is the brake push-rod adjustment. When you check/adjust it you need to actually "feel" the clearance, work the pedal with your hand, don't try to just go by free play with your foot. Not to say there couldn't be other problems as advised; but those problems don't keep pressure on the brake light switch as an un-released master will.

Trans is non-syncro low, downshift to second when slowing, and shift to first when
stopped. In traffic, second will usually get you going again, unless you have come to
an almost dead stop.

Check the motor mounts, bad ones can let the engine move when releasing the
clutch causing clutch chatter.

 

Bill, the peddel was fully out, but I think you may be right about the ord/brake adjustment.

 

She's stock drum/drum...parking brake is off the trans tail{stock}.

 

shorten the rod between the pedal and the master cylinder.

 

yeah, shes all origonal....I kept trying to shift from 3rd to 1st and was starting to find it didn't want to pull back forward enough to engage 1st...kept hitting 3rd...by going to 2nd and then back to 1st seemed to work most of the time....there were a dozen stops at least before we hit that hardeys.

 

When I 1st took off there was no free play,that came 20min after we stopped at the hardeys...I'm starting to think it was hanging up before I even left - I'm surprised she even got that far at that rate.
Thanks for the input on the "stop before you shift all the way down"...I'm only 46...I haven't yet driven any of these old girls much...about 4 miles so far!

 

Yeah, I had this exact same problem with my 37 Chev PU. I was on my way to Mcormick Place in Chicago and I had to pull over every 10 or 12 miles and crack a bleeder to be able to continue on. Good thing I always carry brake, trans fluid and oil and coolant with me. Same thing, brake lites and all. Once or twice when I pulled over I didn't even have to step on the brake pedal to stop. It was the wrong adjustment on the pedal rod, wasn't letting fluid back into the M C. Adjusted the rod at the World of Wheels show and all was good on the way home. The guy who told me what the problem was even gave me some extra brake fluid for the drive back home Sunday night, I have no idea who he was.

 

Good morning, there is a special tool that is used to adjust these brakes properly....really hard to do by "feel", also the rear axle is tapered so you will need a huge puller to get the rear drums off, just leave the axle nut on after you loosen it so the drum doesn't take you out when it pops off. Anything you need to know about this brake system and its components are on this site, doesn't matter your model is earlier....it is the same systemGood luck.

http://www430.pair.com/p15d24/mopar_forum/forumdisplay.php?s=&daysprune=&f=2

 

Reading your further info on the shifting problem, it sounds like you should take a look
at connections on the shift rods. Worn bushings, pins, yokes, or a combination of them can cause that too. It's even more fun when you get the shifter in one gear while the
transmission is in a different one. Had to get out and pull the levers under the hood more than few times to get it back to neutral, so I could start over.

 

Yeah, that was the weird part for me was how it could have a high/hard pedel and have pressure on the system.
Thanks for the hint on the motor mount...she wouldn't shudder on 2nd, 3rd or reverse...just 1st.

 

Learn to double clutch. There is usually about 500 rpm between gears. A little practice and you can shift by the sound of the engine.

 

I'm getting the idea it's the rod adjustment...the guy with the hudson said the same thing.."crack the bleeder" and you'll be ok - only problem there is she'd be fine till the next time the brakes were used, as you said. Hind sight was that in the guys driveway with a slight decline backwards, she didn't roll back at all when I hit the gas and feathered the clutch...that should've been my 1st clue I guess - but I was caught up in the moment of the old car and obviously not paying attention.

 

The PO said he had all 4 lines replaced because he'd heard things like that can happen or inner linings could collapse.

 

Check the pedal return spring. All cars have one. If it is broken or missing, the weight of the pedal can keep the M/cyl from returning all the way keeping the brakes applied and the brake lights on. If you can lift the pedal up even just a 1/4" then that is probably the cause. The return spring should keep the pedal against the floor board and the weight off of the piston. The spring is external and not inside the M/cyl

 

PO said he had taken it back already because the pedel was too high with no clearance....laughing at it now I remember he told me his mechanic owned a ford and the PO has a model A and a model T still....maybe they don't know or like mopars ...just joking! Hmmmm....

 

I'll have to check the spring...thanks for that!

 

Sounds like all your issues have been addressed. Please go to the P-15/D-24 site listed earlier. They will have a ton of info you need to read and understand to get this car to daily driver status and so you are karma-connected to it.

Just to finish the brake thing, heat=expansion. Too much heat and not enough adjustment or release of fluid will heat things up and produce a high, hard pedal because the components and fluid have expanded.
The shifting is a combo of doing something wrong (trying to shift into non-syncro first
without understanding the process) and old, worn, unlubed linkage. Take the time to figure out how the shifting linkage works, check for slop, lubricate it so it moves freely, and adjust it so it's working properly.
Most if not all of this is covered at the site, plus a lot of other stuff.
Best of luck getting it working right and bonding with it.

 

The guys gave good advice on the brake problem. It may be that there is no return spring on the pedal to bring it back up.

The shudder when letting out the clutch in first may mean that there is oil on the clutch or that there are hard spots on the flywheel/pressure plate or that the disk is slightly warped. Lots of people who are used to automatics think that the clutch pedal is a foot rest for driving down the road and cause problems that way. My sister is the queen of that brigade and could kill a clutch in 500 miles when she was in high school.
The guys pegged it on the trans not going into first. Non-syncro first gear means that you need to stop completely before going into first or learn to double clutch to do it. It just usually means that you need to wait until the car is at a full stop and is idling before putting it into first or reverse and is no biggie.

 

Somehow I missed this one...thanks for the info and the link. I'm not sure as to how much of a purist I'm going to be with this car and I'm not usre how well they may take that @ p15d24, but I just joined anyway. Thanks- Bob

 

The shifting thing is all me and I'm going to have to conquer that when the car gets here...as well as the brakes....the whole Karma thing just didn't happen yet as we were only aquainted for a short while, but I intend to fix that. Thanks for the input!

 

The PO said he never did anything to the clutch while he owned it, so I figured a pressure plate and clutch were possibly be in order...flywheel will depend on what she looks like and if there's enough meat to fix any problems via machining. Time will tell.....