Brake Vacuum Pump Replacement

[vza]

I read somewhere where this was an easy job.....NOT. Really tight area to work in and difficult to remove lines and fuel pressure thing. Finally got it off and need to know if a sealant is needed for the gasket? Thanks V

[Smac770]

"brake" vacuum pump, you mean the vacuum pump on the back of the cylinder head driven by the exhaust camshaft? Or is this some other brake specific device somewhere? If it's the one on the engine, it's just the metal gasket, which has to be replaced.

[vza]

Yes the one on the engine. Ok so no sealant...mine had a series of 3 metal gaskets...not sure what hats about. Do you have torque specs for the pump and the high pressure fuel thing that attaches to it? Not that ill get a torque wrench in there anyway. Can I use a regular hose clamp instead of the crimp on type?

[bb-tt]

"brake" vacuum pump, you mean the vacuum pump on the back of the cylinder head driven by the exhaust camshaft? Or is this some other brake specific device somewhere? If it's the one on the engine, it's just the metal gasket, which has to be replaced.

Smac you didnt do the complete seal kit just the one gasket? Asking as i am about to order rtek or whatever it is kit.


edit: RKX kit

[Smac770]

So yours had come apart then. It's a metal gasket sandwich; you'll need a new one, 06H 103 121 J, as it's replace if the pump is removed anyway.

Appears the pump bolts' torque is 9Nm. From the Brake System repair manual. For small range torque, I advise a suitable torque wrench, such as this one:
https://www.tekton.com/1-4-inch-driv...rench-trq21101
I love that thing for when I need to do work with 16Nm and down, vs trying to use that 3/8" drive commonplace one that goes to 30Nm or so.

The hose clamp should be the 21mm one, N10 201 801. Look on the old one, it should say something like 21x7.

You'll need a new HPFP o-ring as it's replace if HPFP removed, WHT 005 184.

The HPFP bolts are both to hand tight, then both to 5Nm, then both to 20Nm. Advised to turn the crank to put the roller at its lowest position to create the least stress on the installation. The fuel line to the HPFP is 20Nm. From the Fuel Injection repair manual.

[Smac770]

Smac you didnt do the complete seal kit just the one gasket? Asking as i am about to order rtek or whatever it is kit. edit: RKX kit

I've not actually dismounted my vacuum pump ever. I did pick up a gasket, but then ran into the issue of the Oetiker clamp. I was going to just pull out the output port and leave it clamped to the hose, but it has that o-ring, which I imagine would need replacement after all these years if I released the load on it. Which then comes to that RKX kit for new internal o-rings.

There was a lot of grime around that output port, so I cleaned it up and checked back and do not see a new grime build up. I don't have any problems with brake vacuum or issues with manifold flap operation or heater cutoff operation. And I burn maybe 1/2qt every ~7.5k miles (my oil change interval). So I don't see a need to dig into the vacuum pump should I dismount it to replace that gasket.

I've not done a smoke test of the head to know if there's even a leak at the vacuum pump; I was just going to replace the gasket while I had the HPFP off for another issue. But then didn't have that bloody clamp.

Regarding RKX, if I needed to do a repair on my vacuum pump, their stuff looks good. This is the correct kit for our engine, and they include the pump to head gasket:
https://www.rkxtech.com/collections/...09-a4-q5-a5-a6
There is another TSI kit for the A3/TT; how it differs I don't know. Also note the comment about MAGNA pumps made in Mexico, if that is yours.

They also sell an HPFP o-ring equivalent based on their o-ring material to get it all in one place:
https://www.rkxtech.com/collections/...wht005184-hpfp
edit - nvm, the pump seal kit includes the HPFP o-ring too, so you don't need it separately.

[bb-tt]

I've not actually dismounted my vacuum pump ever. I did pick up a gasket, but then ran into the issue of the Oetiker clamp. I was going to just pull out the output port and leave it clamped to the hose, but it has that o-ring, which I imagine would need replacement after all these years if I released the load on it. Which then comes to that RKX kit for new internal o-rings.

There was a lot of grime around that output port, so I cleaned it up and checked back and do not see a new grime build up. I don't have any problems with brake vacuum or issues with manifold flap operation or heater cutoff operation. And I burn maybe 1/2qt every ~7.5k miles (my oil change interval). So I don't see a need to dig into the vacuum pump should I dismount it to replace that gasket.

I've not done a smoke test of the head to know if there's even a leak at the vacuum pump; I was just going to replace the gasket while I had the HPFP off for another issue. But then didn't have that bloody clamp.

Regarding RKX, if I needed to do a repair on my vacuum pump, their stuff looks good. This is the correct kit for our engine, and they include the pump to head gasket:
https://www.rkxtech.com/collections/...09-a4-q5-a5-a6
There is another TSI kit for the A3/TT; how it differs I don't know. Also note the comment about MAGNA pumps made in Mexico, if that is yours.

They also sell an HPFP o-ring equivalent based on their o-ring material to get it all in one place:
https://www.rkxtech.com/collections/...wht005184-hpfp
edit - nvm, the pump seal kit includes the HPFP o-ring too, so you don't need it separately.

yeah I ordered the kit before i saw your reply. Have had a small leak for a while (not enough to drip on ground but enough to notice it). Figure while i am either fixing my other leak/or installing catch can will take care of this also. Debating whether to put catch can on just replace pcv and gaskets.

[Smac770]

PCV might break once in a while, but a catch can is an endless maintenance action, imo.
It would be one thing if the catch can just substituted for the dumping of residue into the intake track. But since it also negates the crankcase breather function, I'd pass.

[bb-tt]

PCV might break once in a while, but a catch can is an endless maintenance action, imo.
It would be one thing if the catch can just substituted for the dumping of residue into the intake track. But since it also negates the crankcase breather function, I'd pass.

Yeah my issue is that my pcv is working but with my boost cranked up oil is blowing into the turbo inlet. The ridiculously priced 034 and other kits (with africa plate) don't eliminate the breather function just route vacuum through the can.

[Smac770]

Looked over the 034 instructions and it definitely seems to eliminate access to the breather function.

In the stock arrangement, only during idle is breathing active. The vacuum in the manifold is passed to the block, creating a negative crankcase pressure, which pulls air in from the turbo inlet, which is currently at ambient (as we're idling). When the manifold goes pressurized, that's because the turbo is sucking in air from outside and compressing it, meaning the turbo inlet is a vacuum space. So now any positive crankcase pressure produced by the engine operation can pass to the turbo inlet, as the normal path to the intake manifold is not currently valid.

In the catch can arrangement, the connection to the intake manifold is broken. The crankcase will sit at ambient, the catch can is at ambient, the turbo inlet is at ambient. In fact, the crankcase could be slightly positive, as the impedance of the path from the crankcase to the ambient release at the turbo inlet is not going to be 0. When you power up, there's more blowby, more crankcase pressure, and that's fine, because now the turbo inlet is at vacuum and will pull harder on that positive crankcase pressure.

But you don't get the breather operation, and you don't get the improved efficiency and ring seal of a negative crankcase pressure level when idling. It seems increasing the vacuum of the crankcase improves efficiency, which is no doubt why the engineers (cough, bean counters) at VAG increased the crankcase vacuum with the black top to white top move. But increasing that vacuum also appears to assist ring seal, which is why they attempted the phase 1 for the oil consumption. But the rings were likely so far gone by time the oil consumption was "out of spec" that a little seal improvement was useless.

The stock system has the main oil separator on the side of the block, then the fine oil separator integrated with the breather valve in the "PCV". The only real solution is a tertiary oil separator on each line out from the PCV. Something that passes the vacuum one way, and blocks the oil but not the air going the other way. Kind of like how a vacuum cleaner works. But a vacuum cleaner can only isolate out particles to a certain size, then it has to be able to let "air" leave.

If you're getting significant oil level from the turbo input tube from the PCV, I assume that means there's extensive blow by happening at your boosted performance level? The vacuum at the turbo inlet is then pulling that oil vapor through. Or maybe, like when the PCV diaphragm tears and too much vacuum from the manifold is passed to the PCV, your vacuum level being developed at the turbo inlet is "beyond spec" and pulling the air too hard through the oil separator and fine air separator for them to work efficiently. I wonder if just mounting the catch can between the turbo inlet and the turbo side tube of the PCV would be all the impedance one way and oil filtering the other way that is needed to rebalance things.

[bb-tt]

Looked over the 034 instructions and it definitely seems to eliminate access to the breather function.

In the stock arrangement, only during idle is breathing active. The vacuum in the manifold is passed to the block, creating a negative crankcase pressure, which pulls air in from the turbo inlet, which is currently at ambient (as we're idling). When the manifold goes pressurized, that's because the turbo is sucking in air from outside and compressing it, meaning the turbo inlet is a vacuum space. So now any positive crankcase pressure produced by the engine operation can pass to the turbo inlet, as the normal path to the intake manifold is not currently valid.

In the catch can arrangement, the connection to the intake manifold is broken. The crankcase will sit at ambient, the catch can is at ambient, the turbo inlet is at ambient. In fact, the crankcase could be slightly positive, as the impedance of the path from the crankcase to the ambient release at the turbo inlet is not going to be 0. When you power up, there's more blowby, more crankcase pressure, and that's fine, because now the turbo inlet is at vacuum and will pull harder on that positive crankcase pressure.

But you don't get the breather operation, and you don't get the improved efficiency and ring seal of a negative crankcase pressure level when idling. It seems increasing the vacuum of the crankcase improves efficiency, which is no doubt why the engineers (cough, bean counters) at VAG increased the crankcase vacuum with the black top to white top move. But increasing that vacuum also appears to assist ring seal, which is why they attempted the phase 1 for the oil consumption. But the rings were likely so far gone by time the oil consumption was "out of spec" that a little seal improvement was useless.

The stock system has the main oil separator on the side of the block, then the fine oil separator integrated with the breather valve in the "PCV". The only real solution is a tertiary oil separator on each line out from the PCV. Something that passes the vacuum one way, and blocks the oil but not the air going the other way. Kind of like how a vacuum cleaner works. But a vacuum cleaner can only isolate out particles to a certain size, then it has to be able to let "air" leave.

If you're getting significant oil level from the turbo input tube from the PCV, I assume that means there's extensive blow by happening at your boosted performance level? The vacuum at the turbo inlet is then pulling that oil vapor through. Or maybe, like when the PCV diaphragm tears and too much vacuum from the manifold is passed to the PCV, your vacuum level being developed at the turbo inlet is "beyond spec" and pulling the air too hard through the oil separator and fine air separator for them to work efficiently. I wonder if just mounting the catch can between the turbo inlet and the turbo side tube of the PCV would be all the impedance one way and oil filtering the other way that is needed to rebalance things.

Thanks didnt realize the breather function only occurred at idle. Ecs sells adapter for the pcv to turbo inlet. I like the idea of just installing catch can between there ands still having stock functionality of the PCV. Oh pushing 3 bar with the HPT tune.

[Smac770]

To complicate matters, to really do it well, you'd want a check valve setup that would swing the connection between the PCV and the turbo between a 1) fresh air line when the pressure at the turbo is greater than the pressure at the PCV (time for fresh air breathing) and between a 2) catch can line when the pressure at the turbo is less than the pressure at the PCV (boost time). I don't know anything about the inside of a catch can, so my concern is for when the breathing is happening at idle, the likelihood of that fresh air picking up the junk the catch can has been collecting and transporting that into the PCV. Maybe it's not a relevant concern, but maybe something to ask ECS or 034 or whoever makes your can if it's suitable to flow fresh air through it in the reverse direction of the "catch can direction".

[bb-tt]

should probably start a new PCV/catch can thread as i have mucked up this thread enough

[Spawne32]

If you think that vacuum pump was difficult, you haven't even begun to work on cars. lmao The fact that you can see most of the most bolts with the naked eye makes that job easy.

[A4x]

Do we really need all 4 of these gaskets? I suspect my vacuum pump might be leaking a tad bit of oil. Does the HPFP have to come off to replace the vacuum pump gaskets?

[bb-tt]

Do we really need all 4 of these gaskets? I suspect my vacuum pump might be leaking a tad bit of oil. Does the HPFP have to come off to replace the vacuum pump gaskets?

hhhmmmmmm just did not long ago cant remember but think i used everything in the kit. Really not hard job at all.

[Smac770]

Do we really need all 4 of these gaskets? I suspect my vacuum pump might be leaking a tad bit of oil. Does the HPFP have to come off to replace the vacuum pump gaskets?

Depends on what you plan to replace. The metal gasket is what goes between the pump and head. The large o-ring goes inside the pump. The middle o-ring is for the HPFP, because yes it has to come off to remove the vacuum pump. The little o-ring is for the output port. The large and small o-rings are not what Audi considers serviceable. You won't find any Audi part for them, nor a torque spec for the bolts holding the pump cover on, for example. And you have to be careful not to create more issues for yourself: https://www.audizine.com/forum/showt...mp-port-nipple

If you think it's leaking oil, exactly from where do you suspect that. The pump to head interface, the pump cover, or the pump output port?

[A4x]

If you think it's leaking oil, exactly from where do you suspect that. The pump to head interface, the pump cover, or the pump output port?

I'm gonna take a closer look and grab some pictures. Thanks for the good info as always!

[Theiceman]

do all the parts... you dont want to go back .....

[Eclipsegst97]

anyone know what these items are?
that were in my pump?

https://imgur.com/a/G26MJgA

I pulled the pump out, started cleaning it ,prep for the new gaskets.
I saw these" chewed" up parts of a gasket/ o ring? in the screen

any idea? I assume it is part of that screen originally.

the question is if it is, can I get a replacemnt ( doubtful) or just replace the pump ( likely)

Thoughts
https://imgur.com/a/G26MJgA

[Smac770]

Looks like the o-ring for that oil port on the pump. Audi looks at the pump as a single replacement unit, no reference to spare parts for it. You might see if you can get any answer out of Pierburg, but I've never gotten any response worth the time to read from an OEM.

Possibly they are from elsewhere, but the size and shape do seem to fit that location well. No idea how important it is to creating a seal; if the metal gasket would be sufficient. But whatever task the pieces were meant to do, they seem to have no been doing it for a long time.

[Eclipsegst97]

Looks like the o-ring for that oil port on the pump. Audi looks at the pump as a single replacement unit, no reference to spare parts for it. You might see if you can get any answer out of Pierburg, but I've never gotten any response worth the time to read from an OEM.

Possibly they are from elsewhere, but the size and shape do seem to fit that location well. No idea how important it is to creating a seal; if the metal gasket would be sufficient. But whatever task the pieces were meant to do, they seem to have no been doing it for a long time.

sent an email to rkx who sent me the rebuild kit. in ther how to video i dont see them replacing that o ring. and I "think " i dont see an oring there.


I stil dont know how to remove that vacuum port to change the oring. Sent them an email on that as their video shows a different o ring.. Mine is rattling around so I'm hoping that.s the reason for the gross leak

[Smac770]

You mean the black plastic output port? Two tabs on the front and back side you have to squeeze in.
Are you watching this video: https://youtu.be/xUn2BVzGa_U

[A4x]

I took a closer look at my pump. I think I will order that kit from RKX and replace everything I can.

It definitely looks like my pump has been seeping some oil. A very slow leak, seems to be mostly coming from the vacuum outlet, but it could also be from the pump o-rings themselves.

How did you guys get that clamp off of the vacuum outlet? Just cut it? Replace it with a worm style one should be fine, right?

[Smac770]

Oetiker clamps are one time use. Replace it with the correct clamp.
https://www.ecstuning.com/b-genuine-...ach/n10201801/

[bb-tt]

I took a closer look at my pump. I think I will order that kit from RKX and replace everything I can.

It definitely looks like my pump has been seeping some oil. A very slow leak, seems to be mostly coming from the vacuum outlet, but it could also be from the pump o-rings themselves.

How did you guys get that clamp off of the vacuum outlet? Just cut it? Replace it with a worm style one should be fine, right?

i didn't take clamp off just release the coupler/connector, push in on the coupler and depress the locking tabs and pull out. think it shows in the rkx video or maybe another vid/thread on here.

[A4x]

i didn't take clamp off just release the coupler/connector, push in on the coupler and depress the locking tabs and pull out. think it shows in the rkx video or maybe another vid/thread on here.

I see. Great tip!

[dalmation53]

I have a leak on mine right now and my brakes are stiff whwn stopped but once i get going they act like normal. Seems like the leak is letting escape vacuum right?

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[bb-tt]

I have a leak on mine right now and my brakes are stiff whwn stopped but once i get going they act like normal. Seems like the leak is letting escape vacuum right?

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Most of us changed due to oil leaking from pump.

[dalmation53]

Most of us changed due to oil leaking from pump.

Yup i get my new one tomorrow.

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[Theiceman]

Id be checking the line and check valve between the pump and the booster see if it has a leak.. sounds like the booster is leaking down overnight.

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[dalmation53]

This is the one that maybe failed?

https://www.ecstuning.com/b-genuine-...e/06h133781at/

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[Smac770]

Isn't that on the EVAP line?

If you've looked over the pics I've posted in the past about the vacuum line routing, you'll see it's something along the lines of a split off to the EVAP pump back at the fuel tank, a split off to the brake booster, and a split off to the two solenoids that manage the intake manifold runner control and the heater coolant cutoff valve (but only for B8.0, it's electric for B8.5).

If you're thinking there's a pressure issue in the vacuum lines, then disconnect the line from the intake manifold runner control solenoid and put a vacuum gauge on the line and see what it says. What is a normal value? No idea. Not something I've documented, and shouldn't surprise you Audi doesn't document it either. But maybe someone at some time has tested it.

[Theiceman]

I am not sure where the check valve for the brake booster is in the interconnection SMAC posted but I would think it is right before the booster. The failure is likely between the booster and the check valve or the check valve itself.
Let's see if you still have the symptoms after your vacuum pump repair.

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[dalmation53]

I am not sure where the check valve for the brake booster is in the interconnection SMAC posted but I would think it is right before the booster. The failure is likely between the booster and the check valve or the check valve itself.
Let's see if you still have the symptoms after your vacuum pump repair.

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Yes i will let you know i will install it today around 7pm. Ill post update. Btw car is running strong.

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[Theiceman]

i did an additional oil change after about 500 miles, just to clear any crap out .. after the build, not sure if it did anything but sure made me feel better.

[dalmation53]

i did an additional oil change after about 500 miles, just to clear any crap out .. after the build, not sure if it did anything but sure made me feel better.

I shall be doing one at 1k miles for peace of mind as well.

[Smac770]

The vacuum hose routing for the brake booster is simple:
https://audi.7zap.com/en/usa/audi+a4.../6/611-611070/

Hose 6 will be coming from the split right off the vacuum pump outlet, then to grommet 3 through the plenum wall, then hose 1 to the brake booster. Hose 1 has the non-return valve.

https://www.audizine.com/forum/showt...1#post13792031

Green line in the first pic in my post is going to be that pipe 6, and you can see where it clamps to that grommet 3 along the left side. Take the plenum cover off and inspect/test the hose 1.

[Theiceman]

ah yes just as i suspected .. the check valve is right off the booster .. so i agree totally .. if at first brakes ae bad but after driving they are fine, issue i would suspect is hose 1 or connections. you should be able to come out first thing in the morning and that booster better have vacuum or something is wrong.
you should be able to pop hose one off first thing in the morning and here a big woosh, if you dont , its not holding vacuum. thats why brakes are hard at first , as pump build vacuum it gets easier.

[dalmation53]

So is this the check valve? Screenshot_20201218-133346.jpg

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