Question about changing brake fluid

[RUM4MO]

That SEAT Leon guide recommends twice the quantity of fluid is taken out of RHD cars when compared with LHD, I've not seen that quoted on Audi B8 S4 or VW 6C Polo official workshop manuals, strange!

Surely the pipe runs are near enough the same on RHD or LHD cars, just that the master cylinder moves across with the steering wheel and I'd think the brake lines move across as well.

 

[SuperV8]

That SEAT Leon guide recommends twice the quantity of fluid is taken out of RHD cars when compared with LHD, I've not seen that quoted on Audi B8 S4 or VW 6C Polo official workshop manuals, strange!

Surely the pipe runs are near enough the same on RHD or LHD cars, just that the master cylinder moves across with the steering wheel and I'd think the brake lines move across as well.

I think usually the ABS module would stay in the same place, with only the master cylinder moving depending on driving position.
If the master cyl is on the opposite side of the car to the ABS module you'll have 2x additional long pipe runs across the engine bay.
Also modern cars with traction control can have dedicated 4 channel ABS modules so you have 4x separate lines from the ABS module to each caliper. Older cars with 3 or 2 channel ABS would share pipe and split near the axle again changing the fluid volume.

 

[bahyr]

Mine is LHD

 

[SuperV8]

Mine is LHD

Haha - my RHD is OPPOSITE to this!

 

[RUM4MO]

I've just changed the brake fluid in my wife's 2015 Polo, tried using the cheapie China made vacuum bleeder that uses my air compressor, not too impressed with it, maybe not its fault, but keeping tabs on the reservoir level was tricky, maybe I need to buy one of these "auto top up" things to keep the reservoir full of fluid.
Resorted to my new and as yet unused Gunsons Esibleeder, it leaks air at the top of the fill up charging bottle lid, but I could tolerate that, it also leaked at the cap seal for the reservoir, now that is more than annoying and messy, so that car needed cleaning up and washing away all traces of spilt fluid, I did keep the vacuum bleeder on as well as the pressure one, just to speed up fluid collection.
I think that I'll use my previous Gunsons kit for the next car, and pack paper towelling around the underside of the master cylinder!
I applied a ring of the compatible or equivalent to VW grease to the threads on the bleed valves, that seems to stop micro bubbles appearing in the "output" fluid pipe.

 

[SuperV8]

I've just changed the brake fluid in my wife's 2015 Polo, tried using the cheapie China made vacuum bleeder that uses my air compressor, not too impressed with it, maybe not its fault, but keeping tabs on the reservoir level was tricky, maybe I need to buy one of these "auto top up" things to keep the reservoir full of fluid.
Resorted to my new and as yet unused Gunsons Esibleeder, it leaks air at the top of the fill up charging bottle lid, but I could tolerate that, it also leaked at the cap seal for the reservoir, now that is more than annoying and messy, so that car needed cleaning up and washing away all traces of spilt fluid, I did keep the vacuum bleeder on as well as the pressure one, just to speed up fluid collection.
I think that I'll use my previous Gunsons kit for the next car, and pack paper towelling around the underside of the master cylinder!
I applied a ring of the compatible or equivalent to VW grease to the threads on the bleed valves, that seems to stop micro bubbles appearing in the "output" fluid pipe.

I to have had all these issues with the various pressure/vacuum/pumping 'techniques' leaking/bubbles/running out of fluid... etc..

If all you're doing is routine maintenance and changing the brake fluid (and you're not in a rush - can take 15-30 mins) - trust me (a stranger on the internet ) try the gravity method. No leaks/bubbles/mess.

All you need is a syringe; clear tube, large jam jar and a ring spanner of the correct size for your nipples.

Mark some lines on your jar at 0.1 - 0.2L increments. (put your jar on some scales, and add 100 - 200g of water and mark a line)
Suck out all the fluid you can from the reservoir with your syringe.
Top up with freshly opened new fresh.
Crack open a bleed nipple in the order that makes you feel happy.
Fit clear tube over nipple, and route the tube slightly up then down into your jar (so you can see the fluid in the hose coming out easier)
Sit back, relax with a biscuit and cuppa topping up the reservoir at a leisurely rate. when you have collected the desired qty - maybe 0.2- 0.25l a corner, nip up the bleed nipple, and repeat for all calipers.

 

[RUM4MO]

My cunning plan to mark with indelible marker 0.05, 0.10 ect etc on the cheapie Chinese made vacuum kit waste container failed slightly as they kind of washed off with the fluid, I did consider using a sharp tool to create grooves to avoid that, ah well!
I'd think the issue with the new Gunsons pressure bleeder not sealing would be down to me think "what if for once I use the thicker sealing washer" - as the cap supplied for VW and others is quoted as being fit for use on 2 diameters of reservoir and so 2 seals are supplied, but no where that I can find, says which seal is used with which diameter of reservoir, so I'll change that for the next car.
The unfortunate "bonus" with using that cheapie Chinese vacuum bleeder kit was that when I removed the screw on container at the end of bleeding a front calliper, as it was covered in brake fluid from its previous "emptying" it sort of shot out of my hand and projected its contents along the garage floor - very annoying!!
Next job is to empty the exbaking deep oven tray thing which is full of 1.5ltrs of waste brake fluid and absorbent granules, into a poly bag for placing into the general waste.
I still like the idea of pressure bleeding and you can get a high flow rate and that will always beat a slow gravity bleed in terms off carrying along it any small air bubbles.
I failed to find any "auto fill" bits of kits for sale, okay I could a cheapie Chinese supplied bigger and cheaper than what I bought that comes with an auto fill included, but I don't need another cheapie vacuum bleeder kit - buying that would mean buying a much bigger box to store that kit in a warm dry place - ie airing cupboard - unless I can part with another of my previous Gunsons kits!!

 

[mjgreen81]

Hi all,

Just a quick follow up to this as I completed the brake fluid change this afternoon.

Everything was quite straightforward without any surprises. I don't think the existing fluid had ever been changed as it looked like pond water.

I have a manual so bleed the clutch as well. The plastic bleed screw wasn't torqued tightly so was pretty easy to bleed, presume it came out of the factory like this. You do need a small spanner to get in there though (think it was 11mm). Luckily I had one though.

All in all pretty simple. As I suspected that the fluid had never been changed I bought a 5L bottle of fluid to ensure I had plenty in case if any problems. I probably used around 3.5L although this was probably overkill as I wanted to ensure everything was flushed through.

Just for reference I decided to bleed it in order of furthest caliper from the resivoir first and finishing with the clutch.

 

[RUM4MO]

Very good!

I did buy another cheapie made in China vacuum brake fluid bleeder that comes with an "auto top up bottle" - I have fitted an old Gunsons "VAG" sized metal reservoir cap to it and will buy/use a 1/4" BSP fitting to adjust the existing fitting length to suit my VAG cars. I found that while it will fit my 2011 Audi S4 perfectly as the space above the brake fluid reservoir is unrestricted, on my wife's 2015 VW Polo 1.2TSI, the area near and above the brake fluid reservoir is restricted, but I found that by removing the bracketry for supporting the 2 Lambda probes - one plastic nut and pull off a grooved/threaded body mounted stud, I can create a space so that the bottle can be screwed onto the brake fluid reservoir. That kit comes with 4 tripod sort of adaptors to allow the bottle to sit in/on the brake fluid reservoir and be adjusted so that the correct final fluid "height" is kept at all times including after the job has been completed.
So far so good, I'll change the brake fluid in my car soon and try out this auto top up bottle either with the original vacuum bleeder or probably this latest one to see which vacuum bleeder works best, first I'll check what the fluid capacity of this auto top up bottle is - always handy to know these things!

Edit:- on the subject of seeing the old fluid looking like pond water - I used to have that satisfaction when working on my acquired second hand cars, but for the past maybe 38 years, I've always replaced the fluid at the recommended interval, and when doing that you just do not get a clear indication when all the old fluid has been removed from the system, almost annoying!