Disc Brakes Releasing Slowly

[VTHealey]

I have a problem with front disc brakes on my 66 MKIII. They are releasing very slowly after brake pressure is released. Someone mentioned that old brake hoses can swell or slough off internally and act like a check valve. Anyone heard of this? Once the brake fluid pressure is released, what causes the fluid to return. This may be brakes 101, but I missed that class!

 

[Keoke]

Yes it is possible that the old hoses can fail on the inside and shards of the hose will act like a gate as the fluid attemps to return to the canister.

 

[Lotuswins]

VTHealey,

The hoses could be the culprit, how old are they? It could also be a sticky piston in the caliper, have you changed your fluid religously every two years? Its the rubbers in the calipers which retract the pistons, so that too could be the culprit.

Anyway you look at it, you should tear it down and get it fixed before they seize up.

Jerry Rude
BJ8
Lotus Europa

 

[TimK]

Old brake lines need to be replaced! Mine dragged and wore out one pad. I also rebuilt the calipers so don't know which or both were the culprit.

 

[VTHealey]

The brake fluid was changed about a year ago. The hoses are original I think. I'll start by changing them and see what happens and post the result. Thanks for your input. Nice picture of the hose, I hope mine aren't quite that bad...!! If the problem goes away after changing the hose, I'll cut them open and see what's going on and try to get a picture.

 

[tahoe healey]

May as well change the clutch hose as well as you have to replace and bleed the fluid. Three for the brakes and one for the clutch. Not all that expensive for safety. All these hoses can collapse on the inside and look fine on the outside. It can work like a one way valve allowing fluid to flow one way.

 

[DougME]

My Old Saab had the hoses collapse. Proof it out by jacking car, removing suspect wheel, activating brake then immediately cracking bleed screw. See how much fluid comes out and if this frees up wheel. If wheel frees up it's the hose blocking the fluid. If the brake is still on it's a sticky caliper piston,.