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alexandervdr
12-03-10, 07:09 PM
I finally put the oil in the brake system and did the bleeding.
Cause this is my first experience ever, I don't have a clue if end result is ok or not. Pedal feels spongy in the first half or so but then starts firming up. Brakes do work.

Brakes are from 1993 Granada/Scorpio (5 bolts) and vacuum servo is from Sierra

My question:

1. I needed only 500ml (about 17 fl ounce) or so for bleeding on an empty system. That seems very low, or not?
2. What is the total throw from zero to lock of the pedal if everything is done fine? Mine is about 12 cm (5 inch)

Gazzab
12-03-10, 09:03 PM
I finally put the oil in the brake system and did the bleeding.
Cause this is my first experience ever, I don't have a clue if end result is ok or not. Pedal feels spongy in the first half or so but then starts firming up. Brakes do work.

Brakes are from 1993 Granada/Scorpio (5 bolts) and vacuum servo is from Sierra

My question:

1. I needed only 500ml (about 17 fl ounce) or so for bleeding on an empty system. That seems very low, or not?
2. What is the total throw from zero to lock of the pedal if everything is done fine? Mine is about 12 cm (5 inch)

Do not forget the brace on the pedal assy, it supports the top of the assy from above, this was missing from my sumo which I purchased as a part built project. If the brace is missing the pedals flex the bulkhead and this gives the feeling of being spongy.

Gary

Purple AK
12-03-10, 09:22 PM
A new system will feel spongy untill the brakes have been bedded in for a mile or two.

steve_h
12-03-10, 09:24 PM
make sure the front calipers are the right way round ie: bleed nipple at the top

Steve

chedz
12-03-10, 09:25 PM
Hi,
I had a similar set up and found the brakes very spongey. After many hours of bleeding and effort from myself and others I found the main issue was that it was new pads, new disks and new fluid....it all just needed bedding in. After a short drive and a few applications of the brakes it all stiffened up nicely. An eazi-bleed helped a lot. If you are confident all the air is out of the system and things are fitted the right way, best to give it a drive up and down..after a safety check of course.
You might find its fine.. I did.
Good luck
Graham (pished and on a train)

Vidge
12-03-10, 09:28 PM
I finally put the oil in the brake system and did the bleeding.
Cause this is my first experience ever, I don't have a clue if end result is ok or not. Pedal feels spongy in the first half or so but then starts firming up. Brakes do work.

Brakes are from 1993 Granada/Scorpio (5 bolts) and vacuum servo is from Sierra

My question:

1. I needed only 500ml (about 17 fl ounce) or so for bleeding on an empty system. That seems very low, or not?
2. What is the total throw from zero to lock of the pedal if everything is done fine? Mine is about 12 cm (5 inch)

Hi Alexander

I think you'll find that there is still air in the system. Did you have assistance when bleeding or did you use one of those easy bleed kits.

Also make sure the bleed nipple is at the highest point on the caliper when bleeding so the piston fills with fluid before coming out of the nipple, bleed from the furthest point first and always bleed with two people. I've only got about 3cm of travel on the pedal before it firms up.

Cheers

Andy

bitsilly
12-03-10, 09:38 PM
Presuming the air has been expelled (this is frequently due to some kind of magic rather than science, so get someone who has done it before to help!) the amount of travel depends on pivot points, fulcrum length (of pedal) capacity of master vs slave etc, what is important is that the pedal does not bottom out. If it doesn't then you'll be fine. I hope.
But as Andy says, it sounds like there is still a bit of air left. You can't bleed them too much, so just keep going as long as you can afford, there will usually be a few bubbles that come out later than you would think!
If youre worried, just take it for an MOT.
Good luck.

Sidecarbod
13-03-10, 09:36 AM
I would have thought that 12cm of pedal movement is way too much, but like Graham said they can feel a bit spongy with new components but 12cm!

My pedal moves about 1cm. (Everything is bedded in)

I use a cheapo easy bleed, the one that uses tyre pressure to pump the fluid, I've modified it so that I can use a push bike pump.

You can pump one litre through each caliper without wasting it, that way you can be sure that the whole system is free from air.

wilf
13-03-10, 10:21 AM
Pete - LOL.

Is there anything you haven't modified? :p

Sidecarbod
13-03-10, 10:34 AM
Pete - LOL.

Is there anything you haven't modified? :p

I don't mention the things that I've broken! ;)

alexandervdr
13-03-10, 12:31 PM
thanks all for your well appreciated feedback. I am sure now that something is wrong in my set-up, definitely some air that got trapped.
I used a bleeding kit using tire pressure to pump oil through the "vanes and vital parts", but probably did not insist enough...

alexandervdr
13-03-10, 02:56 PM
Well, if it does not feel right, it probably isn't...

After the bleeding yesterday, when even after insisting no more air came out, I did it all over again today (actually twice around , wheel after wheel). A lot more air came out immediately on the wheel where no more air appeared yesterday. I assume trapped air needs some time to find it's way to the ends. Pedal has been firming up nicely, and end to end throw is now about 2 inches. I may do some more tomorrow. Spongyness is gone, except at the ends where more foot pressure pulls the top chassis metal sheet down (I have a 3rd attachement point of the pedal box here)! That may not be a problem once the vacuum servo does it's job (is this assumption correct?), but I still feel the need to correct. It just does not feel right (see above;)). Plan is to rivet a metal L or U profile at the underside of the top sheet from left to right next to the fixing bolt.

I have now a car with a running engine, suspension, brakes, gearbox, cooling, instruments, most electrics. Time to put the body on!

Sidecarbod
13-03-10, 03:05 PM
Well, if it does not feel right, it probably isn't...

After the bleeding yesterday, when even after insisting no more air came out, I did it all over again today (actually twice around , wheel after wheel). A lot more air came out immediately on the wheel where no more air appeared yesterday. I assume trapped air needs some time to find it's way to the ends. Pedal has been firming up nicely, and end to end throw is now about 2 inches. I may do some more tomorrow. Spongyness is gone, except at the ends where more foot pressure pulls the top chassis metal sheet down (I have a 3rd attachement point of the pedal box here)! That may not be a problem once the vacuum servo does it's job (is this assumption correct?), but I still feel the need to correct. It just does not feel right (see above;)). Plan is to rivet a metal L or U profile at the underside of the top sheet from left to right next to the fixing bolt.

I have now a car with a running engine, suspension, brakes, gearbox, cooling, instruments, most electrics. Time to put the body on!


Good to see that its getting better! :p

Like someone else said, "you can't over bleed the brakes"!

Pete

alexandervdr
16-03-10, 06:48 PM
Good to see that its getting better! :p

Like someone else said, "you can't over bleed the brakes"!

Pete

Indeed, I continued to bleed every day (takes actually only 10 minutes) since the first fill end of last week. Every day I have some more air coming out, less and less, but still. Pedal has firmed up a lot now, only 1 1/2 inch or so before extra pedal pressure starts moving the firewall sheet.