Cbody Bob's 1966 Chrysler 300 coupe

Do you get a pedal when you pump the brakes a few times?

You'll probably need (at least) to do a pressure bleed or bleed it with a vacuum pump, but if you don't get a pedal at all, there's another issue.

Even if it's a bad booster, and it might be, you still should get a hard pedal.
 
Do you get a pedal when you pump the brakes a few times?

You'll probably need (at least) to do a pressure bleed or bleed it with a vacuum pump, but if you don't get a pedal at all, there's another issue.

Even if it's a bad booster, and it might be, you still should get a hard pedal.
I get a little bit with engine off. Start car & pedal easily pushes down. I might try a pressure bleed.
 
The hissing sounds like a bad booster, but like John said even if it's bad you should still get pedal.
 
I’ve got a little pedal with engine off. Say about half of what it should be. Engine on & I have about %20
 
View attachment 248659 View attachment 248660 Well I finally got good fluid comming out of all 4 bleeders. Did a gravity bleed on all 4 corners. Only air I got was on the right rear. Tightened all the bleeders & topped off the master. Still no pedal. When I start the car I can hear a hissing sound under the dash when I press on the brake pedal. Does that mean my brake booster is bad ?
Air in the system for no pedal. Isolate the vacuum hose for the HVAC to assure the hiss is from the booster... and give serious thought to a dual master cylinder.

Finding where the air is coming from can be a PITA. If you gravity bleed with a clear hose, it's a little easier to find the bubbles and isolate...You might have a crappy master cylinder too... it sucks when you can't find a fluid trail.
 
My neighbor came over today & helped me bleed the brakes again. With engine off the pedal feels decent but not quite right. Remember I have the D440 with power brakes. The 66 Belvedere with power brakes & the 77 Fury drag car that’s been converted to manual brakes plus countless other old cars I’ve owned over the years. The 300 just doesn’t feel right. When I started it up it has some pedal now but about half what I think it should. The factory vacuum gauge on the center console reads just under 15 at idle. Press on the brake pedal & the hissing sound starts & the vacuum needle drops to just above 12. So pretty sure the booster is bad. I took the hose off & I have manifold vacuum but it didn’t affect the engine. Cover the hose with my thumb & remove & no change in the engine. So I may have a clogged hose. Anyway I yard drove it & it does now have some brakes. I’ll isolate the booster hose & see what that does. I feel like I made progress today. Get the power brakes working & my dash lights working & she should be ready for some Road time.
 
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Well I took her out for a spin today & she performed very well. I drove her over to the sub division behind me first because there’s no traffic in there yet. She had a little stumble but not too bad. I put a gallon of fresh gas in her first. Then I decide to drive up & down the road I live on a few times. The stumble got better as I drove. May have been the good gas mixing in or the carb warming up. The car is 52 years old & drives like a dream. I’m blown away at how well it drives. I never felt it go into high gear but it doesn’t seem to be reving that high. I got it up to 55. The engine pulls much better now with the new distributor. Still need to do some tuning. I never hit passing gear so I may need to adjust the kickdown linkage. Possible I didn’t hold it down long enough. I don’t think they had part time kick down in 66. Also the hood latch doesn’t hold. The hood popped up but the safety catch caught it WHEW! I do have brakes obviously & I’m now convinced a booster will fix it. I had to hold the brake pedal hard & a little throttle as the vacuum leak affected it in drive at a stop sign. All in all it was a good outing. A guy in one of those Copper colored Ram GTX trucks tried to follow me. I think he wanted to talk with me. I had to jump start it so I didn’t want to stop & talk in fear it wouldn’t restart. I have something to build on now. I’ll order my booster soon. When I got her back home & switched her off she said thank you, thank you, thank you Bob for saving me. You’ve spent more money on me than anyone & im going to reward you for it. Kinda neat that she would say that
 
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View attachment 251829 View attachment 251830 View attachment 251831 View attachment 251832 View attachment 251833 Well I took her out for a spin today & she performed very well. I drove her over to the sub division behind me first because there no traffic in there yet. She had a little stumble but not too bad. I put a gallon of fresh gas in her first. Then I decide to drive up & down the road I live on a few times. The stumble got better as I drove. May have been the good gas mixing in or the carb warming up. The car is 52 years old & drives like a dream. I’m blown away at how well it drive. I never felt it go into high gear but it doesn’t seem to be reving that high. I got it up to 55. The engine pulls much better now with the new distributor. Still need to do some tuning. I never hit passing gear so I may need to adjust the lockdown linkage. Possible I didn’t hold it down long enough. I don’t think they had part time kick down in 66. Also the hood latch doesn’t hold. The hood popped up but the safety catch caught it WHEW! I do have brakes obviously & I’m now convinced a booster will fix it. I had to hold the brake pedal hard & a little throttle as the vacuum leak affected it in drive at a stop sign. Al in all it was a good outing. A guy in one of those Copper colored Ram GTX trucks tried to follow me. I think he wanted to talk with me. I had to jump start it so I didn’t want to stop & talk in fear it wouldn’t restart. I have something to build on now. I’ll order my booster soon. When I got her back home & switched her off she said thank you, thank you, thank you Bob for saving me. You’ve spent more money on me than anyone & im going to reward you for it. Kinda neat that she would say that

Bob: I love the patina. . . Also, regarding the kick down, etc: The FSM has a simple procedure for the adjustment (you need a 3/16 bolt). I just recently adjusted the linkage on my '66 coupe, and it now shifts and kicks down perfectly.
 
Bob: I love the patina. . . Also, regarding the kick down, etc: The FSM has a simple procedure for the adjustment (you need a 3/16 bolt). I just recently adjusted the linkage on my '66 coupe, and it now shifts and kicks down perfectly.
Ok thanks. I’ll check that.
 
With it running and holding your foot on the brake, does it seem like it's missing and just basically runnin like crap? Yep, that's your booster doin that. My 300, I've never really cared for the pedal myself. I've even upgraded to 4 wheel discs and dual vacuum booster and still don't like the pedal, but the action of stopping sure feels good!
Your hood latch? I'd have to look, but I believe that there's a spring that controls that? You've either lost it, or it's come undone.
66 didn't have part throttle kickdown.
That's not the prettiest of paint jobs, but nice to see it on the road.
 
With it running and holding your foot on the brake, does it seem like it's missing and just basically runnin like crap? Yep, that's your booster doin that. My 300, I've never really cared for the pedal myself. I've even upgraded to 4 wheel discs and dual vacuum booster and still don't like the pedal, but the action of stopping sure feels good!
Your hood latch? I'd have to look, but I believe that there's a spring that controls that? You've either lost it, or it's come undone.
66 didn't have part throttle kickdown.
That's not the prettiest of paint jobs, but nice to see it on the road.
The idle gets just a bit choppy. About 2-300 rpm helps it out. I adjusted the hood latch today. It’s a lot better. All the springs & parts are there. It’s likely just wore out. Yea she’s got patina. I can’t afford a new dress for her right now.
 
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