Vacuum Pump Swap

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Al2O3

Al2O3

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I did the foot on brake pedal then start her up test a few days ago and it made no difference to the brake pedal. I tested it a few times over a couple of days and I felt nothing through the pedal when she started up. The Landy seemed to brake ok, but I wondered if I'd just got slowly used to the brakes becoming steadily worse. Bought a replacement Unipump one and it arrived this afternoon. Started fitting it straight away, but had to stop for a monsoon and then several hours rain. Just finished the job. Started her up with my foot on the pedal and felt just the same, pedal didn't move :rolleyes: Jumped out and disconnected the vac pipe from the servo and it was definitely sucking harder that the old one :) When I took the old one off and disconnected the vac pipe a lot of oil ran out :eek: I presume/hope that this means it is carped? Put vac pipe back on and took her for a test drive. Braking felt better, not massively, but better. Pulled back on to the drive, left her running, and went around to smell the exhaust. Definitely smelt loads better, in fact I couldn't notice the burning oil smell. I'm hoping that it's not just wishful thinking, but I'm praying that this has solved my turbo passing oil problem.
Does oil running out of the vac pipe indicate the pump is carped? I would have thought so, but would love someone to confirm either way.
Cheers.
 
Al2O3 said:
Great shout, lynall. If there's oil in there do I need a new servo?
Click to expand...

It was just an idea as the D3 suffers from this due to bad design, there was a vac pipe mod that sort of worked, but not always!
The signs were simple, you had a job stopping with a very hard pedal.

So my thinking was dip for oil, if enough is present suck it out with a vac pump designed for engine oil changes and see if brakes improve.
I would say if pedal improves no you wont need a new servo, see how it goes as they wont be cheap
 
@lynall I've dipped the servo with a 30cm cable tie. No evidence of oil on the end, no oil around grommet or pipe that goes in to grommet. I think the oil must have been settling in the bottom of the vac pipe. When the pipe comes out of servo and down to vac pump there is a low point before it goes back up to the pump. I think its settled in there and got no further.
 
Al2O3 said:
I was expecting to see a bigger difference. The old one must be broken though as it was leaking oil through in to the vacuum pipe and the new one has a harder suck.
Click to expand...
One thing I suspect with mine is that the small o ring which mounts between the master cylinder and the servo was leaking I think this would allow air into the vacuum side and degrade the performance.
Its nice not to have to stand on the brakes to stop
 
raywin said:
One thing I suspect with mine is that the small o ring which mounts between the master cylinder and the servo was leaking I think this would allow air into the vacuum side and degrade the performance.
Its nice not to have to stand on the brakes to stop
Click to expand...
I don't have to stand on my brakes. Didn't with the vac pump I've just took off either :confused:
If the old pump does have an issue that's causing the pressure to push oil through the turbo, then t the same time the brakes have passed two or three MOTs :confused:
 
No, but you are going to tell me he says it does. The vac pump does not have a great deal of power and even if it was pushing some air into the block it would not be a lot, you can put your thumb over the end of the vac pipe [[a good pump ] and it will hardly leave a mark The engine breather system would cope with that. Problem may come if the engine breather system is not right and the vac pump just adds to the issue.
So to sum up vac pump would not directly put pressure and oil into the turbo inlet only into the crankcase and then it is then a case of engine breather problems and or a heavy breathing engine.
 
tottot said:
No, but you are going to tell me he says it does. The vac pump does not have a great deal of power and even if it was pushing some air into the block it would not be a lot, you can put your thumb over the end of the vac pipe [[a good pump ] and it will hardly leave a mark The engine breather system would cope with that. Problem may come if the engine breather system is not right and the vac pump just adds to the issue.
So to sum up vac pump would not directly put pressure and oil into the turbo inlet only into the crankcase and then it is then a case of engine breather problems and or a heavy breathing engine.
Click to expand...
I know, but I've been clutching at straws for a few years now. :(
 
tottot said:
No, but you are going to tell me he says it does. The vac pump does not have a great deal of power and even if it was pushing some air into the block it would not be a lot, you can put your thumb over the end of the vac pipe [[a good pump ] and it will hardly leave a mark The engine breather system would cope with that. Problem may come if the engine breather system is not right and the vac pump just adds to the issue.
So to sum up vac pump would not directly put pressure and oil into the turbo inlet only into the crankcase and then it is then a case of engine breather problems and or a heavy breathing engine.
Click to expand...

+1 perfectly on point with the explanation given.
@Al2O3 with your original build thread going dormant, I had assumed you finally got it all sorted.
Sorry to hear you still haven't got to the bottom of the reported issue.
 
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