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Posted by: carcus Oct 26 2016, 09:55 PM

Brakes sucked when I got the car, leaking caliper, bad master. Got all new wheel bearings, new rotors, pads, master. No leaks in the system. I have to mash the brake pedal down and it still takes lots of effort to stop. My last 914 was not like this. The mechanic adjusted them but think he forgot to check the pedal adjustment. Any tips to this? Am I missing something. This is about the brake pedal movement to stopping the car. Even at a red light I need to use alot of pressure to keep the car from rolling. The brake pedal should not have that much effort. Really makes the car not fun to drive. And there is really no bite to the calipers to slow it down if I have to slam on the brakes.

Posted by: Dave_Darling Oct 26 2016, 10:22 PM

Get rid of that Mercedes 23mm master cylinder. Switch back to a 914 17mm one.

Actually, I'm guessing you have a 19mm one? The 17mm one will require about 25% less effort for the same stopping force. Also check that the floor that the master cylinder bolts to isn't flexing--McMark and Racer Chris both make braces to help keep the MC from moving. And check your brake lines when someone stands on the pedal.

--DD

Posted by: Elliot Cannon Oct 26 2016, 10:28 PM

What break pads are you using and were they bedded in properly?

Posted by: Philip W. Oct 27 2016, 09:52 AM

I have a 19mm MC and I do not have an issue at all with stopping or having to apply that much pressure- calipers were rebuilt by PMB performance, I installed everything but had issues bleeding them- you have to adjuste the venting clearance in the rear and then bleed them - I got help with that from local PCA member and aircooled shop here and they grab hard and stop fast now!!!

Posted by: McMark Oct 27 2016, 11:53 AM

Clarification- Does the brake pedal move a little or a lot?

I suspect, from your wording, that the pedal moves quite a bit before it does anything. If I'm right and that's true then you have air in the system and you need to bleed the brakes more. For whatever reason, 914s are notoriously difficult to bleed fully.

Posted by: pbanders Oct 27 2016, 12:00 PM

From my experience, bleeding 914 brakes and getting all the air out of the proportioning valve borders on being an art form. I could never get it to where I wanted it. It wasn't until I had a mechanic here in Phoenix (Jack Doverspike at Stuttgart Southwest) do a full brake job and bleeding that I ever had a really firm brake pedal. How does he do it? No idea, but I'll bet there are people here who can give you a foolproof procedure that completely purges the system of any air.

Posted by: carcus Oct 27 2016, 12:26 PM

The brake pedal does not go down that far. There is not that great brake bite. You really have to push the pedal hard with a quick stop.

Posted by: carcus Oct 27 2016, 12:27 PM

I had a 19mm one that I bought from Auto Atlanta but it leaked. It was replaced with a 17mm one I believe.

Posted by: Cracker Oct 27 2016, 01:34 PM

From the sound of it I believe you have a faulty MC...with a 17mm MC the pedal should be very compliant.

Tony

Posted by: carcus Oct 27 2016, 02:52 PM

The first one was faulty and leaking. This is another one I had to replace it. I would think 2 bad ones would be kinda rare. There are no visible leaks in the system and the fluid is full. Auto Atlanta mentioned it might be the flex lines. I have not replaced them. I am trying to send the first leaking master cylinder back to Auto Atlanta in exchange for some new flex lines. I will then have those replaced and the system bled again to see if issue is fixed. Auto Atlanta has always taken care of me in the past.

Posted by: The Cabinetmaker Oct 27 2016, 03:02 PM

Nice job. If that doesn't spark a debate nothing will.

Posted by: stugray Oct 27 2016, 04:44 PM

If your flex lines are restricting the flow so much that it is making a "hard pedal" then they are restricted enough to cause the calipers to bind after release.

Jack up one end of the car and spin a wheel and press the brakes.
See if the brakes grab abruptly or slowly.
Then once they have grabbed, release the pedal and see if they release immediately.

Posted by: Dave_Darling Oct 27 2016, 05:06 PM

How is the clearance adjustment on the rear pads?

Use half of the spec; I suspect the published number is intended to be "total clearance" and not "per side".

--DD

Posted by: Mike Bellis Oct 27 2016, 05:45 PM

You are within a few hours drive to PMB. Take it there and have them fix it.

Posted by: jcd914 Oct 27 2016, 06:03 PM

Years ago, I replaced the brake pads (frt & rr) on a 914 and the car just would not stop well. The pedal feel was fine, no air, no slop, nice firm pedal when you stepped on it.

The pads were a no name brand, came in plain white box (we had a service manager that kept trying to save a buck or two) and they just had no bite to them. I went thru the bedding in process, still no good.

I finally convinced the Service Manager that we needed to put in different pads. I swapped the pads out for some Textar pads and we had good brakes again.

Jim

Posted by: zipedadoo Oct 27 2016, 06:22 PM

Does your parking brake work ?

Posted by: 6freak Oct 27 2016, 07:33 PM

you can compress air but not brake fluid there for i dont think its an air issue,,peddle dont move as designed its the MC or peddle gluster.IMO..did you bench bleed the MC to make sure it actually worked before install....dont say its new hahaha the other one didnt work out for ya..id start at the peddles its that or next in line...JMO good luck

Posted by: carcus Oct 27 2016, 09:53 PM

Parking brake works well.

Posted by: carcus Oct 27 2016, 10:01 PM

I did not do the install myself. It was done by a local mechanic. The first failed MC was sent back to Auto Atlanta today and the braided lines will be coming soon. I will take it this time to a brake specialist and get it looked at. Snow season is coming so the car will be under a cover when the snow falls and I will work on it after the season ends. I have bedded in several cars brakes before and know how to do it. I do not think it is a disc or pad issue. I understand these are not power brakes but there is no difference when I got the old seized rear caliper off and had a pair of rebuilt rear calipers installed with the new brake parts. It could be an adjustment issue as well. Right now I have pretty much replaced everything.

Posted by: carcus Oct 27 2016, 10:04 PM

One more thing, when I got the rear calipers, I did get the rubber brake hoses replaced at the same time. Just so confused. I still thing it might be a bleeding or adjustment issue. I have spent way too much money on brakes when I need to get the body work done and pan replaced.

Posted by: 6freak Oct 28 2016, 08:37 AM

its something simple that somebody missed IMO ..when you get going again the first thing id check is peddle movement and MC..good luck you`ll get it worked out

Posted by: carcus Oct 28 2016, 10:14 PM

Yes sir, I think with the right person who knows how to adjust the brakes and the new lines, it should work fine. Funny thing, it seems mechanics now that are younger seem to lose the old mechanical tech and go for all computer scan, replace part. If you bring an old Chevelle or Corvette with a carb.....they get confused. What..........a computer can not tell me what the problem is? What part do I charge the customer for and what part do I replace with the OBD codes? I did this game with a car stereo install today, I have installed at least 10 car stereos on older cars and the one in the 914. Now, take my 2004 Jaguar in for an install, all dash kit, all wires, double din.....$550 labor with rear camera install. But that is an example of new tech vs the old install and stuff we had to deal with.

Funny thing, it seems with these older cars, I traded in a 1987 Maserati Zagato Spyder for the 914, twin turbo....the newer the cars get, the more the cost of repair, but the lack of craftsmen that work on the older cars.

Even body shops hate working on older cars...and damn, if you show them some rust, they shy away. No insurance money quick turn for them.Your car sits in the back of the shop as some old piece of junk till they have time to work on it and fiddle...sorry, just venting.