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Posted by: jeremiah98125 Feb 19 2010, 06:25 PM

So I took my 1.7 out on it's maiden voyage today and having some issues with the brakes.. They worked okay for the first 10 miles, good pressure at the pedal but didn't really slow the car down all that great. Then all of a sudden I totally lost pressure and had to pump them about 5 or 6 times to regain the pressure. Kind of scary here in the city.. So I headed home pumping the brakes a bunch before every stop. As I started pulling into the yard the pressure came back and the felt fine again. And sitting in the yard they feel okay again.. It kind of seemed like a hose burst or something but I don't see any fluid dripping on ground and the level in the master cylinder hasn't dropped any. Any idea what happened and how to fix em? The last service report which was 1,000 miles & 12 years ago said "free up calipers, replace pads, repack bearings". Also, manual says use "J1703" brake fluid, what is that? thanks!!

Posted by: rick 918-S Feb 19 2010, 06:30 PM

Master cylinder died. That would be my guess.

Posted by: yeahmag Feb 19 2010, 06:32 PM

Agreed. Without any external leak your master cylinder is shot. Replace it before you drive it again.

Posted by: dr914@autoatlanta.com Feb 19 2010, 06:38 PM

this is an easy one. The flex lines are clogged or a caliper piston is sticking causing the brakes to stick and boil the fluid losing pressure. As soon as the fluid cools the pedal is back to normal. Could also be a sticking brake pedal but I am sure that you checked that. Master cylinder is probably ok, and certainly not causing the problem you are experiencing.

Posted by: yeahmag Feb 19 2010, 06:39 PM

Interesting take on that... I like it.

Posted by: Dr. Roger Feb 19 2010, 06:42 PM

MC for sure.

Also the pads are probably hardened to the point of losing their friction coefficient. Happened to me with similar time/mileage circumstances.

Just glad you didn't die. =)

Posted by: yeahmag Feb 19 2010, 06:44 PM

Oh yeah... Replacing my old pads made a HUGE difference. You had to stand on the brakes to get the car to stop.

Posted by: jeremiah98125 Feb 19 2010, 08:22 PM

Thanks for the replies. Sounds like I'm gonna be checking out the whole brake system next week.. Any recommendations on what brake parts commonly need replacing? I like to have the new parts before I get into a job.. It's such a pain in the arse for me to work on anything down low on the car since I've only got a dirt/gravel yard to work in. I hope to use the car as a commuter so I want the brakes working awesome

Posted by: Dr. Roger Feb 19 2010, 08:44 PM

i can't imagine any wheel cylinder or MC not being corroded and half locked up if not full locked up after that long.

Posted by: underthetire Feb 19 2010, 09:16 PM

If your gonna do it, call eric and get everything. rubber lines, caliper rebuilt kits at least for the front, some good pads then maybe a master.

Posted by: detoxcowboy Feb 19 2010, 09:19 PM

Brake Problems fixed first is the best idea, even if they work they should be freshly gone over if your the new owner.. You got home safe perfect, perfect first issue.. After this you will be able to stop the car no matter what goes wrong next,, or at least have confidence to do so..

Posted by: jeremiah98125 Feb 22 2010, 09:55 AM

So I pulled off all the calipers, turns out both the rear calipers were dragging from sticky piston I assume.. Probably from sitting with the P brake on for so long.. The brake fluid was black like dirty engine oil. I flushed it out with new fluid and I'm going to work some more on them today and put in new pads.

Posted by: Rav914 Feb 22 2010, 11:04 AM

Any 914 new to me is a complete brake job. Eric does the calipers, I change the lines, and a new MC is a must. Even if the car sits for some time while I collect the $. The ability to stop is more important than the power to go. Just imagine coming around a corner and some little kid is in the street.....

Posted by: Vacca Rabite Feb 22 2010, 11:37 AM

Expect to need to replace the hard lines as well as the soft lines. I have yet to come across soft lines that are removable from the hard line connections w/o destruction - even with line wrenches.

Zach