68 300 power brakes

AlVal74

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good morning!! So, I'm going to be picking up my first 68 300 tomorrow(getting a little antsy). Anyway, the question I have is when I took it for a test drive the brake pedal went to the floor and I had to practically put all my weight on it to get the car to stop. The guy said that he redid the brakes a few years back and probably just didn't bleed them enough. I think that sounded a little sketchy but who knows. Its got power brakes (4 wheel drums). So, what do you guys think is the issue? I plan on converting to discs in front but would like to drive it around a bit before it goes on stands for teardown. Thoughts? Suggestions? Thanks!!
 
good morning!! So, I'm going to be picking up my first 68 300 tomorrow(getting a little antsy). Anyway, the question I have is when I took it for a test drive the brake pedal went to the floor and I had to practically put all my weight on it to get the car to stop. The guy said that he redid the brakes a few years back and probably just didn't bleed them enough. I think that sounded a little sketchy but who knows. Its got power brakes (4 wheel drums). So, what do you guys think is the issue? I plan on converting to discs in front but would like to drive it around a bit before it goes on stands for teardown. Thoughts? Suggestions? Thanks!!
Congratulations!

Inspect the brake fluid and look for leaks around the master cylinder, wheels. Brake fluid should be relatively Amber (not dark brown or black). my hunch is that the master cylinder or brake booster has issues.
Air in the lines usually exhibits a squishy pedal.
Pics of it when its in your possession, please!
 
Thanks! I'll give it a good once over when I get it. Pics will be up when I bring her home
 
Get the discs on sooner than later. You gotta be able to stop these cars. If you don’t have confidence I the braking power, it’s hard to fully enjoy driving them. And I second the notion for pics. Welcome to the ‘68 300 family!

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Would love to. But the conversion kit is rather pricey and I have to wait until its financially feasible.
 
Would love to. But the conversion kit is rather pricey and I have to wait until its financially feasible.

When you get the car, just go through the brake system and make sure everything is in good repair and adjusted properly. The drum brakes on these cars are actually pretty decent for the era from which they come. You can install a dual master cylinder (if not done already), and you may want to replace the booster: If its original, it is probably done or about to be done - same for the wheel cylinders. Also, get a brake shoe adjusting tool and adjust the shoes on all four wheels. If you don't drive like a maniac, the properly set up / repaired drum brakes should do fine until you get the scratch and the parts to do the disc conversion.
 
After years of driving a '67 Imp (with discs), I was a little apprehensive about driving my '67 NY'er with drums. After getting the car the brakes got a good going through, and I got used to them easily. Yes, they're different, but for the driving I do (city/suburban cruising) they're just fine. If you're having to stand on them though, there are some issues, and air in the line might be it. These "final generation" (as I refer to them) drum brakes seem to be better than people give them credit for. Also, make sure you're front end alignment is good to minimize pulling to left/right when braking. Good luck! and we look forward to "seeing" it.
 
Welcome and congrats. Is the pedal hard to push all the time? Or does it push with normal effort and go to the floor? Air in the hydraulic line makes it go to the floor or spongy mushy pedal.

If it always takes both feet to operate the pedal the problem is a bad brake booster. Or no vacuum getting to it. So check the hose and valve for suction in that case. ALL 1968 and newer cars had a dual master cylinder by law.
 
No resistance. Goes straight to the floor and then 2 feet to get it to stop.
 
So, anyone have a link where I can get a reliable MC/Booster combo thats not gonna break the bank and will work when I convert to discs?
 
So, anyone have a link where I can get a reliable MC/Booster combo thats not gonna break the bank and will work when I convert to discs?

Looks like your stuck with a rebuild of your current booster, rather than being able to buy a new one. The Cardone rebuild stuff is sketchy: 1968 CHRYSLER 300 7.2L 440cid V8 Power Brake Booster | RockAuto

Since you will likely have to rebuild the one you have, you should go with Booster Dewy: Power Brake Booster Exchange | Providing Parts for Classic Cars
 
Looks like your stuck with a rebuild of your current booster, rather than being able to buy a new one. The Cardone rebuild stuff is sketchy: 1968 CHRYSLER 300 7.2L 440cid V8 Power Brake Booster | RockAuto

Since you will likely have to rebuild the one you have, you should go with Booster Dewy: Power Brake Booster Exchange | Providing Parts for Classic Cars
I hit the I agree button on Rips post about Booster Dewy, and I will say that hiz word "sketchy" is too kind and to STAY AS FAR AWAY FROM ANYTHING FROM CARDONE AS YOU CAN. ALL THEIR STUFF IS CRAP, Jer
 
So, if I get a drum to disc conversion, do I still need to get the booster rebuilt, or does the kit come with a replacement?
 
Thanks!!! That was a very informative read. Now, the fun of looking for a spindle assembly. I was considering one of those kits, but after reading that, its gonna be built overpowered, not under.
 
If the hydraulic system has air the pedal will go to the floor with a perfect working booster.

Brake shoe adjustment, then bleeding and leak check is first priority.
 
Thanks!!! That was a very informative read. Now, the fun of looking for a spindle assembly. I was considering one of those kits, but after reading that, its gonna be built overpowered, not under.
Unless things have changed recently Sir, Most Kits will have you using parts from General Motors or Phord. In doing a little research you can more then likely build your kit with Mopar spindles AND ALL MOPAR PARTS. Why would you want Brand X junk on your beautiful '68 300 Slabby? Spindles and steering knuckles are all cast iron and I mentioned earlier they're are ah couple guyz on this site with 2000+ C-Body inventories in their back yard. Find Murray Park in Tiffin, Ohio and ask him what you need to convert your '68 to Disc's. And BTW, those cast iron parts can be cleaned up and made shiny again with a little effort. FYI I used '76 '77 '78 New Yorker Spindles and Knuckles to put discs on the front of a 1961 New Yorker 9 Passenger Wagon. And added a '70 300 Hurst 323 Sure Grip on the back end just by moving the spring purch's 3/8" inboard on each side. And I won't bore you with all the other mods I made work on that old Long Roof, Jer
 
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Oh, im not going with a kit anymore, but it seems like finding the spindles (gonna get the rest new, if possible) is gonna be a pain.
 
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