passat drinking water

michael999999

Okay so i have a 2001 passat 1.9 that is drinking coolant. Ive just had the timing belt and water pump done. My mechanic has done a test and the head gasget is okay and there is no water in the oil. im topping up about a litre of water a day.

So any ideas as to what could be wrong?

SeanW

Could be the radiator, or one of the water lines leading to/from it.

Diar

As Sean W said

goz83

Most likely the water lines. Had this problem on a 2001 318iSE. The car needs to be warmed up before checking sometimes, because it may not leak until the warm water is running through the lines.

CamperMan

I did have an audi a3 that drank about a litre a day of water, it turned out that a plastic bit behind the engine where the coolant pipes attached to was cracked, it looked similar to this



once it was replaced, it wasted no water.

michael999999

michael999999 wrote: »

.....
So any ideas as to what could be wrong?

Mechanic isn't great anyway.

michael999999

Just took her for a small spin to warm her up there. Popped the bonnet to open the coolant reservoir and check the level,and the water is pissing from the little pressure release valve underneath the coolant reservoir/container!

What could be causing this pressure and is it normal?

Could it be the valve thats faulty?

goz83

Faulty thermostat perhaps. If the engine is getting cold signals, it runs harder until it's told it has reached optimal running temperature. Kinda like if you had no liver...you'd also be in trouble.

michael999999

goz83 wrote: »

Faulty thermostat perhaps. If the engine is getting cold signals, it runs harder until it's told it has reached optimal running temperature. Kinda like if you had no liver...you'd also be in trouble.

thermostat and rad have both been replaced last week!

Were kind of rumming out of options!

goz83

goz83 wrote: »

Faulty thermostat perhaps. If the engine is getting cold signals, it runs harder until it's told it has reached optimal running temperature. Kinda like if you had no liver...you'd also be in trouble.

...... so it p1sses out coolant

Pkiernan

michael999999 wrote: »

thermostat and rad have both been replaced last week!

Were kind of rumming out of options!

If the system is over pressurising, then there is likely a block in it somewhere.

Run the car briefly, and feel around to check that all the coolant pipes are getting warm.

With the engine at temperature, all pipes should have coolant flowing through them.

Check that both the inlet and outlet of the radiator are warm.

Sounds to me like the work was done incorrectly, or that some dirt/crap was released into the coolant system when the work was being done.

Pkiernan

My post above assumes that the pressure relief valve is functioning normally.
It could be this valve needs replacing.

But coming so soon after a large job on the coolant system, I would be a little suspicious that this valve would suddenly fail.

George Dalton

Sounds like a head gasket problem. It is quite common with them.

michael999999

Pkiernan wrote: »

My post above assumes that the pressure relief valve is functioning normally.
It could be this valve needs replacing.

But coming so soon after a large job on the coolant system, I would be a little suspicious that this valve would suddenly fail.

Would this valve be on the container that you pour the coolant into?

michael999999

George Dalton wrote: »

Sounds like a head gasket problem. It is quite common with them.

he done a test with a suction tube with blue fluid in it, he stuck it in the coolant reservoir and sucked up some fluid and it showed no reaction or change of colour!

Nissan doctor

michael999999 wrote: »

he done a test with a suction tube with blue fluid in it, he stuck it in the coolant reservoir and sucked up some fluid and it showed no reaction or change of colour!

Your not supposed to suck any coolant into the tester so he isn't doing that correctly.

Also, did he only check it at idle and has he done a cooling system pressure test?

kippy

Was the timing belt and water pump due a replacement or did you replace for some other reason?

Why did you get the rad and thermostat replaced?

I'd be looking towards another mechanic at this stage to be honest however I dont yet have all the facts.

michael999999

kippy wrote: »

Was the timing belt and water pump due a replacement or did you replace for some other reason?

Why did you get the rad and thermostat replaced?

I'd be looking towards another mechanic at this stage to be honest however I dont yet have all the facts.

I have just bought the car so we decided to do the timing belt as it was due on it.

when he was doing the belt he said there was a leak on the rad, so we thought that would explain the loss of coolant. we initially thought it was the head gasget!

that didnt work so he thought maybe the thermostat wasnt opening, he felt two pipes one was hot and one was cold. may check these pipes again as a previous poster mentioned a possible blockage. we replaced the thermstat but were still losing water.

Ya ill definately be going to a new mechanic, im just trying to narrow down the possibilities as i have over 350 euro of work done to the car over the last 2 weeks.

in fairness to the mechanic that done the work i have used him for the last 6 years without a problem.

George Dalton

How does the heater work on hot setting?

michael999999

George Dalton wrote: »

How does the heater work on hot setting?

the heater is workin fine.

Just checked the two large pipes coming out of the right hand side of the engine. The one on top was roasting but the one underneath was cold, are they meant to be the same temp? The pipes are probably 3 to 4 inches in diameter maybe less.

George Dalton

Sounds like head gasket definitely. Have seen loads of them with these kind of symptoms.

michael999999

George Dalton wrote: »

Sounds like head gasket definitely. Have seen loads of them with these kind of symptoms.

Cheers for all the replies.

looks like ill be sending it off to be skimmed so.

michael999999

michael999999 wrote: »

.............
looks like ill be sending it off to be skimmed so.

Send it to a different mechanic anyway.

Popoutman

Another possibility is a faulty water pump. I had a pressurising coolant system on my passat at one stage. With a failed water pump, the coolant won't be pushed into the block to be warmed, and the coolant there will start to boil, putting pressure into the coolant system and sputtering coolant out the overflow tank. The fact that you appear not to be getting a circulation of coolant would suggest something along these lines: Dud pump, dud thermostat (not opening at the correct temperature), crap blocking the coolant ducts in the block or head, or the last possibility is a head gasket failure.

Note that the test that your mechanic isn't worth a sh*t on a diesel car as it is a test for carbon monoxide which diesels do not produce in appreciable amounts. He should have taken the fumes from the tank into the tube instead of filling the tube with coolant. One good way to test for a head gasket failure is one that is not the easiest to do on a diesel - that's the proper leakdown test using compressed air into the heater plug port when the cylinder is at BDC with both valves closed and the piston at the bottom. This would push a known PSI into the cylinder and measuring the pressure dropping. If this is done and it is noticed that there are bubbles coming from the coolant reservoir it's almost certainly a head gasket.

Sounds as though the mechanic has possibly screwed up the timing belt / waterpump installation and doesn't want to admit it to you.

unkel

CamperMan wrote: »

I did have an audi a3 that drank about a litre a day of water, it turned out that a plastic bit behind the engine where the coolant pipes attached to was cracked

+1

I have this issue at the moment in my '01 Saab 9-5. Waiting to get a slot at my garage to have the new part fitted. Also leaking about a litre a day here.

@George Dalton - if there is no water in the oil, no oil in the water and no smoke from the exhaust, do you still think it could be a HG problem? Is a leak somewhere not more likely?

The leak is from the prv according to the op, quite likely the pressure is coming from the engine via HG.

Nissan doctor

unkel wrote: »

+1

I have this issue at the moment in my '01 Saab 9-5. Waiting to get a slot at my garage to have the new part fitted. Also leaking about a litre a day here.

@George Dalton - if there is no water in the oil, no oil in the water and no smoke from the exhaust, do you still think it could be a HG problem? Is a leak somewhere not more likely?

Oil and water don't have to mix for the HG to have failed and nor does water have to leak into the cylinders. Cylinder pressure, especially on a diesel, is much higher then the cooling system pressure so with a very slight leak, its the cooling system that would be pressurising.

michael999999

It was the head gasket, replaced and all going fine again!

Thanks for the help!

kermitpwee

Cheers for the update