A little while ago I bought a vacuum brake fluid pump as I wanted to change the fluid on my Octavia.

When I started the job this morning all did not go as I expected.

 

I jacked up the offside rear wheel, removed the bleed nipple rubber cap, wiped the nipple, put an 11mm ring spanner on the flats, connected the brake bleeder and checked that the system held a vacuum

 

I opened the nipple and was surprised that a lot more bubbles than fluid came out of the nipple and after about 6 goes I still had only extracted about 20ml of fluid. The brakes are not spongy and I am bleeding the system to change the fluid and not get rid of any air. I was expecting the pipe to be full of fluid but try as I might I could not get a solid flow of fluid. I assume that air is leaking past the threads of the nipple although I only opened it up just enough to get the fluid flowing. Is it normal to have a lot of air in the pipe when using a vacuum bleeder? As a test I got my wife to press the brake pedal with her hand whilst I opened the nipple and solid fluid came out without any air so it does not look like I have introduced any air into the system.

 

I do have a very old Ezibleed in my garage which I bought to bleed my Morris Marina's (yes I am that old and yes I did buy 2 of them, a 1.3 and a 1.8).

I was not able at the time to create a fluid seal with the master cylinder even at very low (5 psi IIRC) pressures so I do not have a lot of confidence in the one that I have.

 

Is the modern Ezibleeder any better or is the Sealey pump a better bet. I like doing my own servicing and saving money but this job looks like costing me more than letting the garage do it. However I do have my wife's Clio and my Son's Civic that I could also do so if buying a Sealey unit is the way to go then I will get one.

 

What does the team think?

 

Edited 7 August, 20169 yr by Liger1956

Was the nipple actually properly open, or was it just pulling air between the hose and the nipple? They don't make a perfect seal, so always look like they're pulling some air, but I do find them to be far better than an eezibleed. I've done a cfew fluid changes with mine and it's always been a dream to use.

I bagged a Sealey pump from Amazon for £30 and never looked back since.

Steve,

 

Thanks for the reply. I did try with the nipple further open and also pressing on it to try to reduce the air bubbles but nothing worked. When the nipple was closed the vacuum held very well with no noticeable drop. There did, to me, seem to be a lot of air being pulled out but I suppose if this is not entering the system and fluid is being pulled out then it might be working correctly. It just does not look right to me.

Tech1e,

 

You did well. The best I can currently find them at is £37.30 on Ebay. They are slightly dearer on Amazon and do not come with the angled connecter at the master cylinder cap which the Ebay version does have and that I think I will need to get the cap on.

Steve,

 

Thanks for the reply. I did try with the nipple further open and also pressing on it to try to reduce the air bubbles but nothing worked. When the nipple was closed the vacuum held very well with no noticeable drop. There did, to me, seem to be a lot of air being pulled out but I suppose if this is not entering the system and fluid is being pulled out then it might be working correctly. It just does not look right to me.

 

That does seem odd, it might be worth just getting a helper to press the pedal so you can watch what's coming out the old fashioned (but infallible) way with a bit of hose and a jamjar, just in case something strange is going on. 

A vacuum bleeder can pull air past the threads of the nipple, especially if you haven't loosened/removed the master cylinder reservoir cap causing a hydraulic lock, it's the path of least resistance.

A good fit of the bleeder pipe on the bleed nipple is essential otherwise again, air will be drawn into the bleeder pipe.

Both are not a problem per se but can give a false impression of air in the brake circuit.

It sounds like your brake system is air free, just keep an eye on reservoir fluid levels as you bleed, air in the ABS pump means £'s at a garage to purge.

If your eezibleed isn't sealing properly at the master cylinder reservoir, make sure you are using the correct size screw cap and the rubber washer is in good condition.

I use an eezibleed and with 2.2bar tyre pressure the flow of fluid is approximately 300ml/min for the fronts and the rears are probably about half that at 150ml/min.

How do I know... major brake system disassembly!

^ Good point!

 

The whole eezibleed/vac bleeder debate just goes down to what works for you really. This is the one I use - http://www.ebay.co.uk/itm/Sealey-Brake-Clutch-Bleeder-Vacuum-Type-1ltr-VS020-/321925076016?hash=item4af43ad430:g:0ZUAAOSwsFpWTdzU - but it does need a compressor to operate. 

If you have a willing helper who can follow instructions, then why not do it the old fashioned way - pump fluid out (slowly) with the pedal, hold, close nipple, release pedal, repeat, keep an eye on reservoir level.....

In fact I've definitely seen this technique printed in a Skoda/VAG workshop manual as the required final stage of bleeding a system, after using other pressure/vacuum equipment.

I have the most consistent brake bleeds using the Gunson Eezibleed. I bought Sealy vacuum bleeder a few years ago and it just sits the garage unused as I prefer the Eezibled although you must obey the maximum pressure.

CWARD,

 

I thought that the Octavia had a 42mm cap (which is the one that comes with the Sealey unit) but the Gunson website only lists 25mm, 27mm, 44/45mm & 46mm caps for the Ezibleeder. Do you have to use the 44/45mm cap and is that why some people, according to the reviews, have been having trouble getting it to seal successfully?

It may be that the abs hydraulics is preventing flow because of the negative pressure.

If you have a willing helper who can follow instructions, then why not do it the old fashioned way - pump fluid out (slowly) with the pedal, hold, close nipple, release pedal, repeat, keep an eye on reservoir level.....

In fact I've definitely seen this technique printed in a Skoda/VAG workshop manual as the required final stage of bleeding a system, after using other pressure/vacuum equipment.

 

I don't because it's a pain and I'm a lazy bugger... at least I'm honest though 

 

With the vac bleeder, the assistant's job is just to top up the reservoir. I do do one last manual bleed to be sure though.

I'd have to look at mine but I just put on that fitted and as a matter of habit put some Ptfe tape around the threads but that wouldn't make up a 2mm difference. Mine is at least 8 year old so not sure if they changed the contents.

Techie has listed the best tool for the job if you are a DIY'er

 

The vacuum bleeders that are available do the job, but tend to suck air from around the bleed nipple in some cases, even when PTFE is used so if you have changed a caliper and are looking to see if all the air is out of the system then its no good.

 

The Gunson is very cheap but mine never sealed very well so I just used it as a way to pressurise the system and topped up manually rather than using the reservoir and getting brake fluid everywhere.

I have gone for the Sealey that Tech1e recommend.

It should be here later this week.

 

Thanks for all the comments, advice and recommendations.

If you have a willing helper who can follow instructions, then why not do it the old fashioned way - pump fluid out (slowly) with the pedal, hold, close nipple, release pedal, repeat, keep an eye on reservoir level.....

In fact I've definitely seen this technique printed in a Skoda/VAG workshop manual as the required final stage of bleeding a system, after using other pressure/vacuum equipment.

 

Push the brake peddle down too far and you risk inverting the seals on the master cylinder == new one.

 

 

Is the old one you have an imperial thread and the modern one metric?

Edited 8 August, 20169 yr by cheezemonkhai

Mission Accomplished!

 

It was so much easier with the Sealey pressure bleeder. The hardest part was removing the Sealey bleeding cap from the master cylinder when I had finished. I had to use a rubber strap wrench that we have in the kitchen to remove tops from jam jars to get it off as access is very limited but it did not leak. I do not know whether lubricating the rubber seal in the cap with brake fluid would help removal. 10psi was adaquate for the job. Now I have to do my Wife's Clio.

 

Cheezemonkhai - my oginal Eezibleeder has a metal 1" cap for Lockheed systems, metal 2 1/2" cap for metal Girling reservoirs, plastic 44/45mm/1 3/4" for metal Girling and all A.T.E. systems, metal 46mm for plastic Girling reservoirs and a plastic 64mm for plastic Girling reservoirs. So it has a mixgure of imperial and metric.