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either my pump is knackered or the rod is worn, ive heard most people say its the pump & to not waste time swapping the rod, but have just seen this on brickwerks that suggests the tap is "usually" a worn rod!? any help apreciated as its doing my nut in!! :confused:
 

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I read something a while back that suggested that it wasn't the rod or the pump but a small pool of oil that gets trapped in the pump body. The cure (or first step) is to take the pump off, take it apart and see if there is excessive oil within the pump.
I was going to do this exact thing but then mine stopped ticking all on it's own.:confused:

So the oil either moved of it's own accord or I have a small vacuum leak which is preventing the piston from staying in the park position - I'll investigate one day.I: maybe...;)
 

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I read something a while back that suggested that it wasn't the rod or the pump but a small pool of oil that gets trapped in the pump body. The cure (or first step) is to take the pump off, take it apart and see if there is excessive oil within the pump.
I was going to do this exact thing but then mine stopped ticking all on it's own.:confused:

So the oil either moved of it's own accord or I have a small vacuum leak which is preventing the piston from staying in the park position - I'll investigate one day.I: maybe...;)
Didn't know that, will try that one.

Ive just bought the pin as it was the cheaper option! Was going to replace that and see, then if that fails replace pump one day..
 

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I personally would say pump everytime and struggle to see the rod getting worn as its highly toughened as it runs in constant contact with the Cam and would wear away very quickly if it were not........................just my thought
Also be aware there are 2 types of pump and rod
Short spring pump gors with long rod
Long spring pump goes with short rod
2 x shorts = no vaccum
2 x longs = cracked pump housing
 

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As far as I an tell the spring goes weak and you get like a valve bounce effect.

The rod will not help you.
 

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I saved this from a previous forum (not sure which one) so I thought I'd repost it here for reference.
I hope Andy Brown does not mind.T:

My van was suffering the all too common complaint of a ticking vacuum pump (diagnosed with the help of this forum). So a few weeks back I set about fetching it off to add the blob of weld to the push rod.

On stripping the unit I found both the push rod and the pump to be displaying no real signs of wear, and was a little disturbed to think that anyone would recommend welding such a highly finished surface as that on the pushrod.

Having hit a bit of a brick wall, I decided that, with nothing to loose I might as well strip the pump unit and have a look in side it. A very brief guide follows (sorry I didn't take any pictures).

1. Remove the 6 torx headed set screws

2. Carefully remove the 'cylinder head'. The pump is sealed by a O-ring type seal which is fairly robust, and shouldn't be knackered by doing this. Also be aware that there are three valves within this unit, which all tend to drop out if you are rough at this stage.

3. Grip the hex of the pump where the push rods acts (we'll call this the plunger) by whatever means you have available (I ended up using mole grips) and undo the 11mm washer on the piston. The spring will 'let go' when you reach the end of the threads here.

4. Fetch out the plunger, spring, washers and other loose bits, then give the pump body a couple of sharp taps on a bit of wood to get the piston out.

Now then. When I got to this point I found a small measure of oil behind the piston (perhaps a teaspoon full). I firmly believe that this is the cause of the tapping, since it prevents the piston from returning fully thus putting a load of backlash in the system, which in turn causes the ticking.

The blob of weld solution works because the piston is never able to fully return due to the increased length of the push rod (for reference the pushrod on my van was 67.5mm when I measured it during this job) however by doing this, the pump is being over-stroked, the effects of which I am unsure.

I'm struggling to understand why pumping the brakes makes the pump go quiet, however, the bottom line of this exercise is that 1500 miles since stripping, cleaning up and refitting the pump, there has not been any sign of a tick;

THIS IS WITHOUT REPLACING OR WELDING ANYTHING.

To conclude the rebuild in true Haynes style, reassembly is a reversal of the dismantling procedure, I left a smear of oil on the bore in which the piston works, and to get that 11mm nut back on you have to push the plunger down against a bench so that the spring compresses enough to start the nut on the threads poking through the piston, you'll probably need another pair of hands for this bit. Also, be sure all the valves are in correctly before putting the cylinder head back on.

There you have it. Of course the above is based on a sample of only one vehicle, but it is a fairly simple procedure, which at worst loses you nothing, but at best, I believe has the potential to save you £160 on a replacement pump.

Regards,

Andy Brown.
 

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Discussion Starter #9
Hmm thanks for the replies. looks as though ill be stripping the pump before forking out £200 on a new one!! mine ticks a lot worse when the engine is hot & i cant really see how the oil would only do this when hot / thinner. :*
 

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I saved this from a previous forum (not sure which one) so I thought I'd repost it here for reference.
I hope Andy Brown does not mind.T:

My van was suffering the all too common complaint of a ticking vacuum pump (diagnosed with the help of this forum). So a few weeks back I set about fetching it off to add the blob of weld to the push rod.

On stripping the unit I found both the push rod and the pump to be displaying no real signs of wear, and was a little disturbed to think that anyone would recommend welding such a highly finished surface as that on the pushrod.

Having hit a bit of a brick wall, I decided that, with nothing to loose I might as well strip the pump unit and have a look in side it. A very brief guide follows (sorry I didn't take any pictures).

1. Remove the 6 torx headed set screws

2. Carefully remove the 'cylinder head'. The pump is sealed by a O-ring type seal which is fairly robust, and shouldn't be knackered by doing this. Also be aware that there are three valves within this unit, which all tend to drop out if you are rough at this stage.

3. Grip the hex of the pump where the push rods acts (we'll call this the plunger) by whatever means you have available (I ended up using mole grips) and undo the 11mm washer on the piston. The spring will 'let go' when you reach the end of the threads here.

4. Fetch out the plunger, spring, washers and other loose bits, then give the pump body a couple of sharp taps on a bit of wood to get the piston out.

Now then. When I got to this point I found a small measure of oil behind the piston (perhaps a teaspoon full). I firmly believe that this is the cause of the tapping, since it prevents the piston from returning fully thus putting a load of backlash in the system, which in turn causes the ticking.

The blob of weld solution works because the piston is never able to fully return due to the increased length of the push rod (for reference the pushrod on my van was 67.5mm when I measured it during this job) however by doing this, the pump is being over-stroked, the effects of which I am unsure.

I'm struggling to understand why pumping the brakes makes the pump go quiet, however, the bottom line of this exercise is that 1500 miles since stripping, cleaning up and refitting the pump, there has not been any sign of a tick;

THIS IS WITHOUT REPLACING OR WELDING ANYTHING.

To conclude the rebuild in true Haynes style, reassembly is a reversal of the dismantling procedure, I left a smear of oil on the bore in which the piston works, and to get that 11mm nut back on you have to push the plunger down against a bench so that the spring compresses enough to start the nut on the threads poking through the piston, you'll probably need another pair of hands for this bit. Also, be sure all the valves are in correctly before putting the cylinder head back on.

There you have it. Of course the above is based on a sample of only one vehicle, but it is a fairly simple procedure, which at worst loses you nothing, but at best, I believe has the potential to save you £160 on a replacement pump.

Regards,

Andy Brown.
I believe this is the reason the long pin is now obsolete from VW, replaced by the shorter one. The original part was too long and over stroked the pump.
Any repairs should include a new pump accompanied by the shorter pin.

S.
 

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looking for some pointers here. Trying to take the pump off to inspect and the lower bolt is rounded. :* Have tried with a crows foot and no luck. What is the best way to get it off? Is cutting through the bolt a good option? I am thinking with the limited space and my delicate piano fingers it could get either bloody or very wrong. Can the the thread bolt be replaced?

Cheers up front for any advice here as its me first time trying this.

Goodomens
 

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The problem is due to a manufacturing error, lack of regular oil changes and/or build up over time even with the corretc oil changes.

The pump ids designed to be angled so oil will flow back into the engine, however VW in their wisdom angled it back so the oil gets trapped.

So an oil change and drain of the excessive oil might fix it, however if there is a long term build up of oil and sludge, it usually means a new pump.
 

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Been reading about this as i think i have the same problem. Initially i just thought it was a rattly tappet as the van has done a LOT of miles, but when i bounce on the brake pedal a few times it goes suggesting it is the vacuum pump according to this here forum.

But, the ticking will return after a few seconds, maybe 8 - 10 seconds. Can anyone confirm its the pump? And, should i get it done? Might something bad happen if i dont?! :*

Cheers ... :ILU:
 

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Been reading about this as i think i have the same problem. Initially i just thought it was a rattly tappet as the van has done a LOT of miles, but when i bounce on the brake pedal a few times it goes suggesting it is the vacuum pump according to this here forum.

But, the ticking will return after a few seconds, maybe 8 - 10 seconds. Can anyone confirm its the pump? And, should i get it done? Might something bad happen if i dont?! :*

Cheers ... :ILU:
That sounds exactly like it's your vac pump. People have driven for thousands of miles with it rattling away, but I couldn't cope with listening to it knowing it wasn't 'right'.
 

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That sounds exactly like it's your vac pump. People have driven for thousands of miles with it rattling away, but I couldn't cope with listening to it knowing it wasn't 'right'.
Thanks very much mate, a proper answer! T:
My issue (apart from the fact i dont have a clue what a vacuum pump even does!!) but my issue is that on tickover it just sounds awful, but after a couple of pumps it sounds great. I reckon I'm gonna get it sorted, thanks again!! A:T::) :ILU:
 

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just to warn anyone doing this them self. If you are a how and then DIYer like me, getting the pump back on is not the easiest thing to do. I don't know how to turn the engine to TDC so resorted to a wooden chock under the pump to push it up into position and hold it there whilst I got the top nut in and then wedged it some more to get the bottom one started. Definitely get an assistant as it saves getting out from under every 2 mins to tighten the top then back under for the bottom etc.

Cheers,

goodomens.
 

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either my pump is knackered or the rod is worn, ive heard most people say its the pump & to not waste time swapping the rod, but have just seen this on brickwerks that suggests the tap is "usually" a worn rod!? any help apreciated as its doing my nut in!! :confused:
I have replaced loads of these over the years and fit a new follower as there cheep anyway. I have 3 old ones and can see that the hex nut part is More worn on the noisier pumps giving more clearance and knocking will post a pic if wanted
 

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I have replaced loads of these over the years and fit a new follower as there cheep anyway. I have 3 old ones and can see that the hex nut part is More worn on the noisier pumps giving more clearance and knocking will post a pic if wanted
yes please pics if you don't mind , im thinking of doing mine in the near future
 
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