Lotus Europa Community
Lotus Europa Forums => Garage => Topic started by: marks on Monday,September 14, 2020, 07:33:16 AM
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I am a new member to the forum with my first post; and I am in the process of restoring a 72 Europa Twin Cam basket case. The calipers have been rebuilt with new brake pads and the brake master cylinder has been rebuilt. The brake pads do not release and I can not turn the tire with the car up in the air. The brake pedal seems hard and there is not a lot of travel. I did try releasing the bleed valve to no avail. I did take the caliper off the rotor and the discs seem to move in and out okay. The caliper was a bit tight to reinstall on the rotor. I am hoping that someone might be able to help me; before I venture to the liquor cabinet. Thanks! Mark
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- Did you replace the brake hoses? Old hoses can act as one way valves when they break down internally.
- Is there free play at the pedal? Try taking the clevis pin out at the pedal and see if that releases the front brakes
Other than that, welcome to the forum!
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Just double checking, you opened the caliper bleed nipples and they still would not turn?
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:Welcome: marks!!
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The calipers have been rebuilt with new brake pads and the brake master cylinder has been rebuilt. The brake pads do not release and I can not turn the tire with the car up in the air. The brake pedal seems hard and there is not a lot of travel. I did try releasing the bleed valve to no avail. I did take the caliper off the rotor and the discs seem to move in and out okay. The caliper was a bit tight to reinstall on the rotor.
Hi Mark, and another :Welcome:
As John says, did the wheel stay jammed solid when the bleed nipple was opened and fluid dripped out ? If so then my first thought would be sticking pistons although some brake pad materials are known to stick to iron discs if they are put away wet.
The last sentence is interesting when you say it was tough to get the caliper on. If the pistons are free then they should move to let the caliper go on. By any chance is the caliper body rubbing on the disc/rotor ?
A servo can apply/hold the brakes as well, especially if there's not enough free movement at the m/cylinder push rod/brake pedal. For reference I think I had around 4-5cm of travel at the brake pedal on the standard Europa TC setup. More than 5cm feels "wrong", less than 3cm sounds like something is wrong somewhere.
Brian
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I have had the pads stick in the calipers on Europas, (and on a Toyota Corolla GT rally car just before a very fast tarmac stage which I had to do with zero brakes).
Do the pads move freely in the caliper?
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It sounds like your master cylinder is not retracting all the way. There is a compensating port. If it is staying covered, fluid won't return to res and brakes will not release pressure.
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Thank you very much for all the responses! I should have started on this site when I began this endeavor. I did replace the brake lines with a new braided style. I did try to bleed at the bleed nipples and nothing happed. The caliper body does not seem to be rubbing. I also appreciate the spec on the pedal travel. I will try taking the clevis out. I went on the wagon in 1984 and this has almost pulled me off it. Every one stay safe! Mark
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Sorry for being repetitive:
- the wheel won't turn
- open the bleed nipple
- the wheel still doesn't turn
Correct?
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No problem on the repetitive:
The wheel does not turn
I did open the bleed nipple
The wheel does not turn
This time I completely disconnected the brake line and the wheel would not turn
The pads were new but many years old
Is it possible that they may have swollen over time; or that I may have the wrong ones in?
A possible solution might be to order new pads or grind the existing ones down?
I appreciate all the help; as this car came in boxes and nothing was labeled
I have the manual; but everything is not crystal clear in it.
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Thanks for the clarification.
You don’t have a hydraulic issue. You have a mechanical issue. Remove the pads and see what’s up.
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I'm still not clear if the problem is with one wheel or with all four wheels. If one wheel and fluid came out when you opened the bleeder nipple and the wheel still won't turn, the pads may be preventing the disc from turning. If no fluid came out, then it may be a hydraulic problem. If all four wheels are locked then look at a likely hydraulic problem.
Never mind, read the title, face plant.
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I have ordered new pads to see if the fit is better. I am hoping for the best! Thanks for the help!
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Please don't order anything just yet. REMOVE the pads and see how it is after that. Are the pads tight? All of them? Just inside ones? Just outside ones? Something else with nothing to do with the pads?
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I had to grind small bits off the metal backing plate to make the pads move in the calipers.
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I removed the pads; and they all seem to be tight; both sides.
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They should move along the two pins freely, but not too freely. .
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Pads removed, are the wheels now free?
You can sand excess pad thickness off with sandpaper and a flat surface.
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Pads removed, are the wheels now free?
You can sand excess pad thickness off with sandpaper and a flat surface.
My problem was the metal backing plates were rough and didn't slide in the calipers properly, not the thickness of the brake pad material.
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I solved one of the problems on my brake issue as the pads were too thick for the rotors. Second problem: I have rebuilt the brake master cylinder and there is pressure coming out of the rear port (closest to the firewall) but no pressure coming out of the front port. Suggestions?
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I solved one of the problems on my brake issue as the pads were too thick for the rotors. Second problem: I have rebuilt the brake master cylinder and there is pressure coming out of the rear port (closest to the firewall) but no pressure coming out of the front port. Suggestions?
Air! Are you trying bench bleeding?
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Yes, I am trying bench bleeding.
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35 year as a mechanic and I don't rebuild brake masters anymore. I only fit new. When I'm screaming down a mountain pass, I want them to work. If you are restoring a trailer queen then originality comes into play. Driver? Just fit new.
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35 year as a mechanic and I don't rebuild brake masters anymore. I only fit new. When I'm screaming down a mountain pass, I want them to work. If you are restoring a trailer queen then originality comes into play. Driver? Just fit new.
46 years as a mechanic - ditto
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I appreciate the feedback buying a new brake master cylinder. It seems like originals are not out there. Is there one that I can use with the same port line set up, that will work as an original? Thanks for the help!
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What is the bore size of your original master cylinder?
Do you have twin brake boosters?
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He says it's a 72 TC, so the unobtainable MC. There are on this forum several alternatives. I have a Triumph Spitfire MC with remote reservoirs. I think there's a Grumblebuns post listing alternatives people have tried.
I had fitted the Datsun MC, lovely light bit of kit, but eventually it failed and can no longer be found. Shame!
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Still want to know exactly what "Marks" has before making a recommendation.
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I do have the 2 brake servos.
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Do you know the bore of the master cylinder?
Are the boosters still hooked up?
Myself, heretic that I am, I would remove the boosters and "miles" extra piping.
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The boosters are still hooked up; and I will have to check on the bore. Thanks!
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With dual boosters, the master has an 0.875" or 7/8" bore. Without the boosters, they used a 0.700" bore. Here's an article one fitting Spitfire master cylinders to Europas:
http://www.lotuseuropa.org/LotusForum/index.php?topic=1818.0
My advice would be to ditch the 50 year old boosters and go for a 0.700" master.
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I bypassed my boosters in my 73 twin cam special. I used a Tilton 74 series master cylinder 3/4" bore. Part number 454-74-750U. I bought it from JEGS. It cost $75.65. I did not need a proportioning valve. The master bolts right up, you don't even have to change the bolts or the rod. I did not use the remote reservoir. I have driven the car for only 500 miles but the brakes felt good. You will also remove about 25 lbs. from your car. I put stainless bolts with stainless washers and stainless dome nuts in the six vacant mounting holes. Plus, I now have extra room so I mounted a radiator over flow bottle connected to the swirl tank.
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That's a single circuit master. Nothing wrong with that. I run one myself. Just wanted to make sure Marks knew. Lots of people sell Girling, or Girling-clone, single masters in sizes from 5/8 to 7/8. If you go that way, I would recommend at 0.70 master. It gives slightly longer travel than a 3/4" but is easier to modulate at the limit.
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Thank you very much for all the information! You guys are great! I am presently trying to unstick the front cylinder of the master cylinder. I am keeping my fingers crossed; hoping that I only need to hone the front part of the master cylinder to get it operating without sticking.
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I would not run a single circuit master. Loosing your only circuit in a Europa is probably death.
I'm far from stock but I'm running a 5/8 front and 3/4 rear and then re drilled my pedal arm to get a better ratio and feel.
If you go unboosted with a larger bore you will need to increase the pedal ratio to get decent feel and modulation.