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Discussion Starter #1
I was bleeding all of the brakes on the car and ran into some problems. I blead the inside if each caliper first and worked my way from furthest to closest to the reservoir.
The problem that I am having is that when the car is off the brake pedal obviously is super firm. When I start the car there is barely any brake pedal, am I missing a step somewhere? I have done quite a few brake jobs in the past and never had this problem before.
 

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Pumping it up with car off and the pedal should get relatively stiff. This because there is no vacuum assist with the car off. (all cars are like this)
Thats the best way to tell if you have air in the lines. Once you start the car it will feel somewhat more mushy with the vacuum assist vs with the car off.
It shouldn't go to the floor with car on, is that what is happening?

Edit: How are you bleeding? Gravity? Two-person? Vacuum bleed?
 

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Discussion Starter #3
It gets close to the floor but doesnt go completely down. Feels a bit mushy, I am certain I have got all of the air out of the lines.
 

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It gets close to the floor but doesnt go completely down. Feels a bit mushy, I am certain I have got all of the air out of the lines.
As long as its pretty hard with the engine off, I don't think there is much else you can do. The pedal gets more mushy with engine on because it has more force to flex all the components (lines, seals, pad, calipers, etc) theres a lot of hydraulic pressure in there
 

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Discussion Starter #7
I did a complete hellcat conversion to a 2015 300..
So I had to put new lines on the front and bleed all 4 corners.


 

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Yes I used the same master cylinder.
I just looked its same master as the hellcat, which you probably already knew that.
Thats probably where the different feel comes in. The 300 master only has to push fluid to 2 piston on each side total of 4 vs 6 per side total of 12 for the hellcat calipers. The master is going to have to travel that much further to move all 12 of those pistons (hence more clamping force due to hydraulic compounding effect) .

You test drive it yet? I bet it stops on a dime.
 

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Discussion Starter #11
I have not test driven it yet, I am going to get a new lower oil cooler line ordered today. When I start the car the oil leaking from the factory clamp is pretty significant.
 

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I occasionally get the hard brake pedal on start myself. I don’t think it’s anything to worry about.
 

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I was bleeding all of the brakes on the car and ran into some problems. I blead the inside if each caliper first and worked my way from furthest to closest to the reservoir.
The problem that I am having is that when the car is off the brake pedal obviously is super firm. When I start the car there is barely any brake pedal, am I missing a step somewhere? I have done quite a few brake jobs in the past and never had this problem before.
You want to start at the wheel furthest away from the master cylinder and IIRC the bleed screw furthest away.

If you or someone manually works the brake pedal you want to be careful you do not push the brake pedal down all the way as this will have the piston in the master cylinder moving into an area of the cylinder it has not been in before. A new master cylinder is probably not a problem. But one that has been used might have developed some rust/corrosion in that heretofore unused portion of the cylinder and if so this can damage the master cylinder piston and its seals.

Techs I have observed use a pressure bleeder setup. I have used a pressure bleeder system and it worked pretty good. I found it better to not put any fluid in the pressure bleeder but just use it to pressurize the brake fluid reservoir. 'course one had to keep an eye on the level to avoid it going too low and introducing air in the lines. By not filling the pressure bleeder with fluid there was no post clean up necessary. The techs do brake bleeds all the time and the pressure bleeder doesn't require cleaning between uses.

Besides not letting the fluid get too low the other thing to be mindful of is to not use too much pressure. IIRC for one car the max was 21psi but I kept it down around 15psi just to be safe. Brake fluid is very light fluid and doesn't require much pressure to force brake fluid out the bleed screw.

My Hellcat manifests the "super firm" brake pedal once in a while. Not often. I believe this is due to a loss of "boost" vacuum (or pressure) from the car sitting unused. But it can also arise from working the brake pedal.

(One of my previous cars has a power assist hydraulic clutch system. The way to test if the assist system was working was to with the engine off push the clutch pedal all the way down then release the clutch pedal and repeat this until the clutch pedal required considerable effort. I think the number of pedal pushes was around 30. Then once the pedal effort got hard to start the engine and let it run for 20 or 30 seconds. Then shut it off and verify the pedal effort was again light.)
 

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Discussion Starter #14
I started the car today and I sat In the drivers seat this time, my neighbor was the person who led to believe the pedal wasnt where it should be. I felt no problem what so ever with the brake system. I even took the car for its maiden voyage around the neighborhood and everything was fine!
He must not be used to a Chrysler brake pedal!
 
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