Loosing/leaking water but no one know's how

[4lps]

Hi guys..

1.9 Tdi, 130 BHP, 2001, Y reg

I have acquired a water leak which is causing my daily water fill-ups.
I do over 50 miles a day and mid-way through my journey the STOP warning light comes on, I have to stop and wait a few minutes and top it up with water before I continue my journey. The difference I have notice it during short, low speed journey it seems ok, but the level goes down slowly. On a normal working day it takes me over an hour to get to work and the car speed varies, if I get a clear road I tend to push it a bit more and the warning light will most defiantly appear. When I do fill it up even on a morning I notice there is still a lot of pressure in the header tank. I do notice its all rusty water near the header tank overflow and it leaks a few drops.

Symptoms and fixes so far

1) The car has been Pressure tested twice and it has been confirmed it is not the water pump/head gasket? Are they right, could there be an internal problem.

2) The heating matrix pipes have got a T piece on, eliminating leaks inside the car, the foot wells have been checked too. But its damm cold in the car!!!

3) Brought a new cap after that was suggested but its the same.

4) I noticed the temp go wild, so slowed down and it went back to normal, during that time I notice the heating didn't work.

5) An old skool mechanic I know has attached a pipe from the over flow to a made-up empty container and filled it with water to act as a overflow to the heather tank and I didn’t get the problem driving to work???? Can any one shade some light of what it could be…


Thanks

Almistry@hotmail.com

[Col]

Hate to say it but if the temp goes up under load / at high speed and then quickly goes down when you ease off, then probably head gasket failure.

Note that the failure seldom shows up under normal tests (pressure etc).

Also be aware that Passat radiators are prone to leaking on the engine side lower corners. A leak here is almost impossible to spot. I'd say the rad was the cause if the temp didn't shoot up under load.

Saying that, the temp sensors are very unreliable and you may have (if your lucky) a dodgy temp sender and a leaking radiator.

However and as above it is probably the head gasket. Do look at the rad and do replace the temp sensor first to be sure.

[4lps]

Hi, Thanks for the response

The temp doesn't alway go high on load, only occassionally.

if it's Rad problem I will be able to get it changed as I only replaced it less than 12 months ago.

The temp flying up is a recent thing but never the less it does do it,.

Since I've had a pressure done twice and nothing came up... is there different type of pressure test or test that can be done to diagnose this weird problem? or are all pressure test the same.

Thanks

[Jamie 1984]

I had the same problem with my golf tdi i had a presure test and couldn't find anything, Then i saw the water bubbling up and out the over flow on the header tank, i asked a mechanic he said its the water pump i got it changed and it solved the problem.

[4lps]

I had the same problem with my golf tdi i had a presure test and couldn't find anything, Then i saw the water bubbling up and out the over flow on the header tank, i asked a mechanic he said its the water pump i got it changed and it solved the problem.

Hi Jamie,
You were absolutely right, after further investigation it has been confirmed as the water pump, they figured this out by taking of of the pipes off and realising the water wasn't flowing how it should. The water was ONLY escaping from one place, the headertank over flow, after pressure build up, so most people would guess and say its the head gasket but it wasn't.

Since my timing belt is due in 8k, I'm getting all the belts, the tensioner and full service via a friend at VW.

I have changed the headertank but this didnt have to be done.

Thanks

Alps

[4lps]

Hi guys

Its back to the drawing board for me.. I have now had my water pump, timing belt and other belts all changed. Drove to work all good, 2 mins into the journey on the way home the water light/coolant warning comes on, so I top it up thinking its just circulating, 1 hour into my journey a 2nd top up of 1 litre..

Can anyone help, spend loads on the car already... every hour I'm loosing water out the header tank so it seems.. The gaskets the only thing not changed.. & thermostat???

Please hellllllllllpppppppppppp..

ta

Alps

[jason 99]

have a look at engine block for sighns of leaking water. without being patrenising its usualy brown rustic water colour. Theres a aluminium or some kind of metal pipe at the back of your engine which sometimes rusts causing a leak. I had similiar problems on my sisters megan and thought the worst head gasket) however it turned out to be a leak on the pipe I am refering to which I mended using flexi rubber and fixed it on with a jubilee clip. hey presto problem solved.

Have you checked the oil to see if there is water in it. I know there doesnt have to be for head gasket to have gone however the amount of water you are losing would suggest that there would be if it was the gasket.

[4lps]

have a look at engine block for sighns of leaking water. without being patrenising its usualy brown rustic water colour. Theres a aluminium or some kind of metal pipe at the back of your engine which sometimes rusts causing a leak. I had similiar problems on my sisters megan and thought the worst head gasket) however it turned out to be a leak on the pipe I am refering to which I mended using flexi rubber and fixed it on with a jubilee clip. hey presto problem solved.

Have you checked the oil to see if there is water in it. I know there doesnt have to be for head gasket to have gone however the amount of water you are losing would suggest that there would be if it was the gasket.

Hi jason

The oil has been checked, got a oil change just to check the oil all ok there.

One of the garages said they saw a leak at the back of the engine but didn't know where, I'll have the garage to locate this pipe.

Thanks for you reply, I'm willing to try anything as even the guys at the main dealer are confused.