Brakes almost go to the floor....HELP!!!

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318MoparGuy

318MoparGuy

MoparHokie
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Waynesville,NC
Hi All,
I am new to the site as I have just purchased a 1973 Dart Swinger, it had a 225 in it before and now has a 318 in it. Front end was rebuilt new, he added V8 torsion bars and added front sway bar, subframe connectors welded in and such. I just wish the guy would have upgraded the braking system also. The car has factory front disc brakes and drum rears (all new and new hardware too). When I depress the brakes they go almost (about 1" away) to the floor...the brake light doesn't go on, but it's a BIG safety concern to me that this is happening. Is this how brakes were in 1973 and was there a manual disc brake vs a power disc brake option? I just posted pics of the car (Yellow Dart) on the Welcome Wagon (New Kid on the Block) if you need to see the master cylinder type. What are my options to remedy this safety concern and upgrade the braking power? Does having rear drums complicate this situation? Is there an easy way to do this as I am not at all well-versed in this area. Thanking everyone in advance for taking the time to help me resolve this problem and looking forward to everyone's thoughts on this matter. You guys and gals are the BEST!!!! Thanks again...
All the Best,
Greg
 
I have to wonder if this is the somewhat typical "calipers on the wrong sides" scenario.
Can you pump the brakes and make a higher pedal ?
 
Oklacarcollecto said:
Sounds like a bad master cylinder, brakes need bled or brakes need adjusted.
Click to expand...

This is a good place to start. Plus does the pedal have a lot of free travel before you feel resistance? May have the wrong push rod ( the rod between the brake pedal and the back of the master cylinder). I would start with bleeding the brakes to make sure there is no air in the system. Find someone to help you with brake knowledge. Make sure the rear brakes are adjusted correctly.
 
RedFish said:
I have to wonder if this is the somewhat typical "calipers on the wrong sides" scenario.
Can you pump the brakes and make a higher pedal ?
Click to expand...

True. make sure the brake bleeder is located on the top side of the caliper and not the bottom.
 
Could be several things. No reason to assume that just because the warning lamp isn't on, that the lamp or the pressure switch actually WORKS

Time to dig in. Read a shop manual. Inspect it. Condition of pads? Looking at the position of the bleeders is a good idea. Have you checked fluid level? That might be a clue, if it's low. Rear brakes may be way out of adjustment, adjusters corroded/ rusted/ stuck, etc,

You don't necessarily need to upgrade anything-- just properly fix what's there.

The other thing is, you may have a mismatch of parts. If the rear axle is a swap, or the master cylinder not original, the rear cylinders may be too large bore, or the master too small, etc. You may have the wrong master/ pushrod in the pedal hanger assy.

Very first thing I'd do is check fluid level, condition of pads and position of bleeders, then tighten up the rear shoes until the tires won't turn and see if that brings the pedal up. If it does, adjust the rear brakes.
 
RedFish said:
I have to wonder if this is the somewhat typical "calipers on the wrong sides" scenario.
Can you pump the brakes and make a higher pedal ?
Click to expand...

I'll have to check that out...and I can't make a higher pedal by pumping the brakes...I just checked to make sure that I did put in original question that car is a 1973 Dart Swinger...phewww,,,glad I did...thanks.
 
SGBARRACUDA said:
This is a good place to start. Plus does the pedal have a lot of free travel before you feel resistance? May have the wrong push rod ( the rod between the brake pedal and the back of the master cylinder). I would start with bleeding the brakes to make sure there is no air in the system. Find someone to help you with brake knowledge. Make sure the rear brakes are adjusted correctly.
Click to expand...

Yes the pedal has a lot of free travel before I feel resistance...master cylinder looks to be original, so push rod hopefully shouldn't be a cause and will check rear brake adjustment...thanks for your input.
 
SGBARRACUDA said:
This is a good place to start. Plus does the pedal have a lot of free travel before you feel resistance? May have the wrong push rod ( the rod between the brake pedal and the back of the master cylinder). I would start with bleeding the brakes to make sure there is no air in the system. Find someone to help you with brake knowledge. Make sure the rear brakes are adjusted correctly.
Click to expand...

Yes it does have a lot of free travel before I feel resistance. The push rod might be wrong as I don't know if it is the original master cylinder and I will check out bleeding the brakes and adjusting the rears...thanks for your input.
 
67Dart273 said:
Could be several things. No reason to assume that just because the warning lamp isn't on, that the lamp or the pressure switch actually WORKS

Time to dig in. Read a shop manual. Inspect it. Condition of pads? Looking at the position of the bleeders is a good idea. Have you checked fluid level? That might be a clue, if it's low. Rear brakes may be way out of adjustment, adjusters corroded/ rusted/ stuck, etc,

You don't necessarily need to upgrade anything-- just properly fix what's there.

The other thing is, you may have a mismatch of parts. If the rear axle is a swap, or the master cylinder not original, the rear cylinders may be too large bore, or the master too small, etc. You may have the wrong master/ pushrod in the pedal hanger assy.

Very first thing I'd do is check fluid level, condition of pads and position of bleeders, then tighten up the rear shoes until the tires won't turn and see if that brings the pedal up. If it does, adjust the rear brakes.
Click to expand...

Will check all the basic stuff..fluid level,adjustment,pads and such. Rear axle is original to car and will check position of bleeders....need to start learning curve...thanks for your help.
 
Step 1 would be to "bleed the brakes", i.e. replace all the brake fluid until you get clear fluid, w/ no bubbles from each wheel cylinder/caliper. I know that is a pain, but should be a regular maintenance task every ~2 yrs, unless you use DOT 5 (silicone) fluid. Some who fear DOT 5 say it isn't a big deal to do this regular bleeding.
 
I agree with changing the fluid, I use a turkey baster to suck the fluid out of the MC, it saves a little time. Just be sure not to dribble any on the paint.

You just bought the car so no idea how the PO took care of it. Adjust the brakes up until you hear a very slight drag when rotating the wheel. It's also a good idea to put a piece of 3/4 inch wood or something under the pedal when bleeding, to avoid pushing the pedal tight to the floor and possible off set your distribution block.

Start at the right rear to left rear to right front to left front. In other words start at the furthest point from the MC and work your way to the closest.
 
There must be a half dozen people on this planet that change brake fluid regularly.
Yet everyone is stopping. Go figure. Changing the fluid at this stage is a waste of time and money. The first thing to do is visually inspect everything. If you don't know what you're looking at or looking for, either get yourself a service manual or let a more knowledgeable pair of eyes upon it.
In certain conditions you could bleed gallons of fluid through it and not make any difference at all in the braking.
 
You know one trick I use to find out if the rears are causing this is to press the pedal with the car running, and then set your ebrake (this holds the shoes all the way out to the drums) then see how your pedal feels with the ebrake still on.
If it feels good you need to adjust the rear shoes.
If it makes almost no difference it's something else.
 
I didn't read where you "bench bled" the MC itself first. That is essential. You often need ~50 pedal strokes to get all the air bubbles out, which you will never do just running fluid thru the whole system. You don't need to remove the MC, indeed I prefer installing it in the car first so I can use the pedal. You route special tubes from the ports back to the reservoir for this. They come in most rebuilt MC boxes, or you can buy separate or make your own metal tubes. Many videos on youtube.
 
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