Brake Fluid Replacement Guide

Brake and clutch fluid replacement guide. Warning this guide is aimed at those with mechanical knowledge but is simple enough to be done by most. If you get it wrong, don’t blame me. Brake fluid must be handled with care as it strips paint and car ruin bodywork and wheels. After a ‘boiling’ moment on a track testing day I checked out my brake fluid to see it was black! Looking at the various brake fluid options, I decided to go for Castrol Response Super Dot 4. This is a decently priced (about £11 a litre) high temperature fluid which was recommended by quite a few people on the forum. I bought two litres of the stuff to give the system a good flush. You will need; 2 Litres of new brake fluid A Pressure bleeder 10 mm spanner 6mm spanner (or adjustable spanner) Half a metre of 6mm clear flexible hose A few bowls to drain the old fluid into Trolley Jack Axel stand Wheel chocks 8mm socket & ratchet Allen key to remove the 2 under tray bolts Looking at the price of pressure bleeders (£120) I decided to make my own as per Muchers idea. I bought a garden pressure water sprayer (£12), a second hand brake fluid reservoir cap from a Vectra (£2) and some Araldite glue. I cut off the end of the water sprayer and measured the diameter of the hose (9mm). I took an 8mm drill bit and drilled a hole in the reservoir cap and pushed the hose through the hole. Leave about an inch sticking through the cap and Araldite both sides to get a good seal. Once dry I tested the system by screwing the cap to my reservoir and pumping in some pressure. Once pressurised you must listen for air leaks from the cap, even the slightest can cause problems. Now the testing is done it’s time to fill up the bleeder and start flushing the old fluid out. The front wheels can be bled without removing the wheels as the bleed valves are easily accessible. Before you jack up the rear of the car ensure you can access both front bleed valves (if the wheel is in the wrong position the spokes can stop easy access). Remove the rear under tray, chock the front wheels and jack up the car from one of the rear points, place an axel stand under the other point and lower the jack so the car is even and both rear wheels are off the ground. Remove the rear wheels. Re-attach the bleeder (with fluid inside) and pump in some pressure. Not sure how much to put in but I opted for about 20 pumps which worked fine. Start from the rear passenger side wheel. Remove the rubber cap from the bleed valve and attach the clear flexible hose to the end of the valve, it will fit perfectly. Position the bowl under the end of the hose and use the 8mm spanner to open the bleed valve. The value is a screw type and only needs to be opened slightly (about 1 full turn) to start the process. Through the clear hose you will be able to see the old fluid draining out, when the colour changes from black to yellow close the valve and remove the hose. Dry up any remaining fluid on the calliper and re-fit the rubber cap. The first calliper will take the longest as it drains the old fluid from the reservoir. Move to the rear driver side calliper and repeat the procedure until the new fluid runs through. The VX uses the fluid in the brake reservoir for the clutch, so this will also need bleeding. Access to the clutch bleed valve is tricky as there is not much room in the engine bay. The valve is on the top of the gearbox toward the passenger side. It is obscured by a hose leading to the aux water pump. From underneath the car, feed in the hose at the front of the gearbox from the passenger wheel arch. Position a bowl under the hose to catch the fluid. In the engine bay, remove the rubber cap from the valve and fit the hose to it. Open the valve with a 6mm spanner (I used an adjustable as my spanners only go down to 8mm). Once again watch the fluid till the new stuff comes through. Close off the valve and dry up any excess. Remove the hose and re-fit the rubber cap. Finally move to the front passenger wheel. Repeat the same procedure for the rear wheels through the spokes. Be careful not to spill and fluid on the wheels as brake fluid is really good at stripping paint. If any gets on the bodywork or wheels wash it off with soapy water immediately. Finally do the drivers’ side in the same way as the others. If you look at your reservoir you will notice the black fluid is gone and the system is full of brand new fluid. Release the pressure on the bleeder (which should suck the overfill from the tank), and unscrew the bleeder. Re-fit the cars reservoir cap, put the rear wheels back on, remove the axel stand and jack, then re-fit the under tray.

ummm worth mentioning that halfords sell easy bleed pressure bleeding kits for about £16-20..... saves faffing about making one.
like this http://www.carparts-...e_Bleed_Kit.cfm

and that taking the undertray off isnt nessecary, infact its better to leave it on as there is somewhere to place the fluid catching device

Edited by slindborg, 10 October 2007 - 07:17 AM.

The idea in removing the under tray is to jack up the rear wheels so that both sides can be done straight after each other.

Edited by SteveA, 10 October 2007 - 08:02 AM.

What about all the fluid in the ABS system? Don't you need a Tech 2 machine to run a special program to activcate and flush that out?

want a problem for mine when I bled it without tech 2....... I think its more of a myth to get you to goto vauxhall "specialists"

When you say it wasn't a problem, what do you mean exactly? It wouldn't be a problem, no - just means that a portion of your fluid (the stuff sat in the ABS pump, valves and pipes) doesn't get replaced.

Edited by Jase_MK, 10 October 2007 - 08:30 AM.

Mine took far far far more fluid than was expected...... and the fluid hasnt change colour as yet (and the fluid was defaintely ranted round the ABS system a few times after trying the new fluid and pads lol) but hey what does that matter huh.

The ABS system fluid is only an issue if you are bleeding manually and introducing air. A pressure bleeder system will avoid this problem.

Fair enough. I replaced mine a couple of times using one of those halfords pressure things that takes pressure from a tyre valve. Never did the ABS and didn't have any probs but just wondered what happened to all the old fluid sat in the ABS system.

I bleed all four corners without jacking up or removing the wheels, good old speedlines

I bleed all four corners without jacking up or removing the wheels, good old speedlines

Same with NA wheels

I bleed all four corners without jacking up or removing the wheels, good old speedlines

Same with NA wheels

Well I did the brake/clutch fluid on my VXT (standard wheels) at the weekend without jacking up, removing wheels or undertray!

Edited by ronbot, 10 October 2007 - 07:33 PM.

I bleed all four corners without jacking up or removing the wheels, good old speedlines

Same with NA wheels

Well I did the brake/clutch fluid on my VXT (standard wheels) at the weekend without jacking up, removing wheels or undertray!

I did it with one eye closed, and one arm behind my back

I bleed all four corners without jacking up or removing the wheels, good old speedlines

Same with NA wheels

Well I did the brake/clutch fluid on my VXT (standard wheels) at the weekend without jacking up, removing wheels or undertray!

I did it with one eye closed, and one arm behind my back

I thought this thread was about bleeding the brakes, not your strange interpretation of the Kama Sutra

The ABS system fluid is only an issue if you are bleeding manually and introducing air. A pressure bleeder system will avoid this problem.

Yes, note to self. Don't empty all the old fluid out by forcing air through, doh! I seem to be most of the way to remedying it using the standard bleeding technique.

If I replace one caliper (rear pass side) will I get away with just bleeding that corner? Cheers. Chris

If I replace one caliper (rear pass side) will I get away with just bleeding that corner?

Cheers.

Chris

Attach the pressure bleeder, clamp (or bung) the hose to keep the pressure and fluid in while removing the caliper (fluid will p*ss out so you will need to be quick). Once the new caliper is on un-bung/clamp the hose re-attach it then bleed the caliper using the valve on top. As long as the bleeder is on and has plenty of fluid and pressure you shouldn't introduce any air in the system pre-caliper. The bleed from the value will push out any in the caliper. Other corners wont need bleeding.

If I replace one caliper (rear pass side) will I get away with just bleeding that corner?

Cheers.

Chris

Attach the pressure bleeder, clamp (or bung) the hose to keep the pressure and fluid in while removing the caliper (fluid will p*ss out so you will need to be quick). Once the new caliper is on un-bung/clamp the hose re-attach it then bleed the caliper using the valve on top. As long as the bleeder is on and has plenty of fluid and pressure you shouldn't introduce any air in the system pre-caliper. The bleed from the value will push out any in the caliper. Other corners wont need bleeding.

Splendid, thanks.

Chris

Cheers for the guide. Did mine today for the first time. The guide was really useful and I've learnt quite alot doing it.

Worth mentioning that the most contaminated fluid will be in the reservoir. Sometimes there will be thick jelly in the bottom wich you don't want to push into the system when bleeding. To avoid this do the following; 1.Before bleeding cut zip ties holding reservoir in place. 2.Pull resevoir off and up. 3.Remove filler cap and tip fluid away. N.B. Hoses stil attached. 4.At this point its possible to pull off hoses and clean out the reservoir. Nice to do as it all looks nice and clean when refilled with new fluid. 5.Re-attach hoses and refit reservoir. 6.Refill reservoir ready for bleeding. N.B. No air is introduced into the system as resevoir is highest point in system. Also when you start bleeding you are flushing new fluid through system straight away and not introducing contaminated fluid from reservoir.