Where did my brakes go?
6 posts
• Page 1 of 1
My breaks are all gone. Lucky enough, this happened today in the garage as I was going for a ride. I have been searching in the archives, and I suspect the servo. I would be very greatful if any of you experts could help me...
The breaks have been fine the two last years. However some months ago, they became a bit soft, with a short pedal travel before they became effective. Simultanously, a soft hissing sound was heard from the brake system beyond the torpedo wall. Thid did however not affect the effectiveness of the brakes, and the car passed the MOT in June. I did not take this seriously.
Soon after, I started bleeding the breaks as I suspected air bubbles had entered the system. My plan was first to recycle the brake fluid, but when I noticed the brake fluid included various nuances of black and brown, I decided to change fluid. Except for the brown and black part of the fluid, which settled in the bottom of the bottle I used, the fluid had a tint of yellow-green. I had no information on what type of fluid was used. Dot 4 or Dot 5? I made a test and as it blended fairly with water, I decided it was not silicone-based, and I filled the system up again with Dot 4 fluid. In a test drive shortly after, I noticed brake effect was perfect. But there was still a hissing sound, with little brake effect in the initial pedal travel.
This was made two weeks ago, and I spent my time wondering if I did a bad job exchanging the fluid until this afternoon. What happened today was that I started my engine and started rolling out of the garage. But when I applied the brakes, there was absolutely no resistance in the pedal, but still a hissing sound in the end of the travel. When I opened up I found that there was no fluid in the container, but no puddles under the car! Where did the fluid go?
I have a late +2 with dual brake circuits and two servo units, and with the twin cam running I localized the hissing from one of the servo unit. Could it be that servo is the cause? I have also noticed that an oily fluid have dropped from the brake peda = brake fluid? Could it also be that I have filled the brake system with wrong fluid, so that the soft components of the system have disintegrated (= black part of used brake fluid), or is it the master cylinder that has failed. And where is the brake fluid hiding???
/Ulf
The breaks have been fine the two last years. However some months ago, they became a bit soft, with a short pedal travel before they became effective. Simultanously, a soft hissing sound was heard from the brake system beyond the torpedo wall. Thid did however not affect the effectiveness of the brakes, and the car passed the MOT in June. I did not take this seriously.
Soon after, I started bleeding the breaks as I suspected air bubbles had entered the system. My plan was first to recycle the brake fluid, but when I noticed the brake fluid included various nuances of black and brown, I decided to change fluid. Except for the brown and black part of the fluid, which settled in the bottom of the bottle I used, the fluid had a tint of yellow-green. I had no information on what type of fluid was used. Dot 4 or Dot 5? I made a test and as it blended fairly with water, I decided it was not silicone-based, and I filled the system up again with Dot 4 fluid. In a test drive shortly after, I noticed brake effect was perfect. But there was still a hissing sound, with little brake effect in the initial pedal travel.
This was made two weeks ago, and I spent my time wondering if I did a bad job exchanging the fluid until this afternoon. What happened today was that I started my engine and started rolling out of the garage. But when I applied the brakes, there was absolutely no resistance in the pedal, but still a hissing sound in the end of the travel. When I opened up I found that there was no fluid in the container, but no puddles under the car! Where did the fluid go?
I have a late +2 with dual brake circuits and two servo units, and with the twin cam running I localized the hissing from one of the servo unit. Could it be that servo is the cause? I have also noticed that an oily fluid have dropped from the brake peda = brake fluid? Could it also be that I have filled the brake system with wrong fluid, so that the soft components of the system have disintegrated (= black part of used brake fluid), or is it the master cylinder that has failed. And where is the brake fluid hiding???
/Ulf
1974 Lotus Elan +2 130/5
- Uboat
- Second Gear
- Posts: 170
- Joined: 21 Sep 2007
I had exactly the same thing with my sprint when reversing out of the garage many years ago - empty master cylinder
Cause: Servo failure. Some fluid was in the Servo - I'm sure some had been burnt through the engine via the vacuum feed.
Was the engine running rough or was there white smoke trail the last couple of times you used it ?
Richard
Cause: Servo failure. Some fluid was in the Servo - I'm sure some had been burnt through the engine via the vacuum feed.
Was the engine running rough or was there white smoke trail the last couple of times you used it ?
Richard
Richard
'72 Sprint
'72 Sprint
- richardcox_lotus
- Coveted Fifth Gear
- Posts: 1098
- Joined: 11 Jul 2004
When I read the post initially it sounded like the seals had gone on the master cylinder and the fluid had been dumped into the driver's foot well which has happened on my plus 2 once. I do agree with the other posts about there being a good chance that one of the servos has blown, however, it is very strange on a dual system that you should have had no brakes at all. I would therefore still suspect the master cylinder. Would be good to check both servos and to renew the seals on the master cylinder as a matter of course.
Cheers
Andy
Cheers
Andy
Live life to the fullest - that's why I own a Lotus
- handi_andi
- Third Gear
- Posts: 392
- Joined: 04 Feb 2006
6 posts
• Page 1 of 1
Total Online:
Users browsing this forum: No registered users and 14 guests