Club 80-90 Forums

I have been having a problem for the last few months which I cant work out,every morning on start up the brake pedal is solid.

I'm pretty sure its the Vacuum pump but after replacing it with three different s/hand ones the problem still persists.
I have a Vacuum guage and am getting no vacuum on early morning start up. After one to two minutes (depending on which pump) the vacuum starts sucking.

Having at first tried two s/hand pumps I thought it can't be that and changed the servo, same problem.
As GSF have discontinued the replacemment pump the only way I can source a new one is from VW@ around £125.
I have no problems paying this but want to get some expert advice first,as If it doesn't fix it I am liable to set fire to the van.

Its deffinitely not a leak in the pipes or one way valve as when the pipe is removed even after leaving overnight, there is the sound of rushing air.....
It cant be the intermediate shaft as it drives the oil pump through the vacuum pump (I think).

could it just be that once these Vacuum pumps are left lying around they stop working properly?

Luckily the pumps I have purchased have been not a lot more money than the postage so I cant complain about that.

Can I be unlucky enough to have three plus my original pump inoperative?
the only thing I have not changed is the master cylinder, but I cant see that being intermittent.

many thanks Rob..............
ps. have also posted this on Brickyard.

Wot engine is it?

1.6d n/a JP engine from a golf, but apparently 1.6d/1.6td all share the same Vacuum pump.
Rob.

It can only be the one way valve or leak between one way valve and servo.

Not a syncro is it?

The valve is fine x 4( only blow one way) and I get a rush of air when pulling the pipe off, and thats after leaving it all night.
plus if I pull the elbow out of the sevo, wait for the Vacuum to start (minute or two) and replace, the brakes work fine again until the next morning.
Rob....

lhd wrote:The valve is fine x 4( only blow one way) and I get a rush of air when pulling the pipe off, and thats after leaving it all night.
plus if I pull the elbow out of the sevo, wait for the Vacuum to start (minute or two) and replace, the brakes work fine again until the next morning.
Rob....

If its holding vacuum overnight it would indicate a servo problem but if that has been replaced i don't know.

If its holding vacuum overnight it would indicate a servo problem but if that has been replaced i don't know.

Surely the pump should produce vacuum as soon as the engine starts othrwise when you push the pedal,releasing the vacuum.
Theres no suction to replace it?

From the begining! Fit pump, (without pipe on) Start engine, Stick finger over pump! Ouch or no ouch? If you indicate an ouch your pump is working!

Then your next port of call! The pipe (the one with the hole in it) Does it suck as much as at the ouch part?? No? This would indicate a holed or blocked/crimpped pipe!

Block one end of the pipe and blow down the other end! ( i hope you can hear it hissing out somwhere) if not! undo the block and blow again to check if it clear!

Keep it simple youl get there!

From the begining! Fit pump, (without pipe on) Start engine, Stick finger over pump! Ouch or no ouch? If you indicate an ouch your pump is working!

no ouch thats the problem, even when I rev it up((without pipe) and thats been on all four pumps, yet after a minute it works as good as new.
also once it works the vacuum is strong at the servo end of the pipe.

maybe I have just been unlucky because if I swap the pumps around none of them start producing vacuum as quick as my original one.

lhd wrote:

From the begining! Fit pump, (without pipe on) Start engine, Stick finger over pump! Ouch or no ouch? If you indicate an ouch your pump is working!

no ouch thats the problem, even when I rev it up((without pipe) and thats been on all four pumps, yet after a minute it works as good as new.
also once it works the vacuum is strong at the servo end of the pipe.

maybe I have just been unlucky because if I swap the pumps around none of them start producing vacuum as quick as my original one.

remove oil filler cap and test again.

remove oil filler cap and test again

will do.......
thinking about it this all started after an oil change, before heading off to Amsterdam.
Hey thanks for the help guys, shalll check in the morning.

Do you have oil trouble also?
Is the timing belt slipping over the intermediate shaft pulley?
Is the woodruff key intact?

No oil trouble...
will check your other two points tomorrow.

Ok the timing belt is not slipping and it makes no difference if the oil filler cap is off.
I removed the vacuum pump earlier and briefely started the engine.
There was air blowing out of the hole like an exhaust pipe or hair dryer, is this right?
I have also noticed that the pumps seem to be full of oil, a little more than just lubrication as it is making its way to the one way valve.
There is nothing blowing out of the oil filler cap.

Rob when andy has shrunken his avatar i may be able to see your post

jed