RickBetterley

I use a pressure bleeder on the track car (1995 993 with stock calipers). Each winter year I flush the system.
This winter it seems that the flushing is extremely slow; there is no obvious obstruction, bleeder nipples are open the usual amount, and pressure on the bleeder is the normal level. Same slow rate on all 4 wheels.
Any suggestions as to why the fluid would be flowing so slowly?
Thanks in advance.

chris walrod

I often times find 964's and 993's with this sort of trouble while bleeding brakes. With a bleeder open and the pressure bleeder connected, I'll ask someone to tap the brake pedal to give the system a little push. This usually clears-out any sludge or that milky white coagulated brake fluid, as I tend to call it.

After a tap of the brake pedal while at each corner of the car, it usually makes the next round of bleeding like normal. By next round, I mean I will go around the car one more time for a final bleed.

dcdude

I was taught to start the engine briefly for the pedal tapping at each corner. Not certain of the incremental benefit. The other problem might be the MA winter...go Giants!

clubsport1

I had this and the technician said it would make sense to change the bleed nipples next time to make things easier/

RS man

I agree with Chris,

I used my hand to gently push the pedal rather than using foot to avoid excessive pressure as you only need a small amount of pressure to get the flow going.

Harry

RickBetterley

Great advice; thank you.
CHRIS - what's with Knightsbridge? I'll be there there in a few weeks. I love the variety of cars parked along the streets (exotics); what a waste.
Chuck - I knew somebody would comment on the winter, but the car is in a warm (though not heated) garage - 50+ degrees.
Who are these Giants to which you refer?

Bill Verburg

I've never seen that waxy build up seen in the brake fluid in a 993 in other cars no matter how poorly maintained. Anyone know what causes it?

Sound like Rick has it in a very well maintaned system.

RickBetterley

Bingo - I tried this today and worked beautifully. I was a bit surprised to see how much crud came out.
In the future I think I will include the brake tap with the pressure bleed.
Thanks, Chris and everyone else that helped.

chris walrod

Good work. Glad it helped. I maintain a RSA for a friend and quite a famous vintage racing motorcycle collector, that I ended up completely removing a bleeder nipple with 10psi on the system -- still no fluid flow! I applied a little hand pressure on the brake pedal, still no flow. Had to climb in the car and use my foot -- after pressing quite hard, it finally blew out -- wow!

The Knightsbridge avatar I had last week was from a picture I shot while in the 'tube' system in downtown London. Quite a system they have there that seems to be a pretty efficient way to get around. My wife and I enjoyed the experience!