I'm losing coolant :(

**njek** · 29-03-2010,09:40 PM

My Passat has recently developed an annoying problem, in that it is losing coolant. However, it's all a bit weird...

I noticed the problem a week or so ago. I'd driven into work in the morning, with no problems. However, when I got in the car in the evening to drive home, the info display immediately told me to switch the engine off, and check the coolant. Pretty much all the coolant from the expansion tank had gone. I topped up with water, and drove home with no extra problems.

Since then, I've noticed that long journeys result in very little coolant being lost, but short journeys result in a lot of coolant being lost.

Does this make sense to anyone?

The coolant is dripping from the front of the car, from the lower lip of the bumper. I've tried looking at the radiator, but can't see anything obvious. Next step would be to remove the bumper to take a closer look, but it's such a pain to do on the Passat, that it's a job which will have to wait until the weekend.

Tonight I have put a bottle of RadWeld in, left it idling for 30 mins, and it hadn't lost much coolant at all. The test might be tomorrow morning's drive to work.

Any help/advice would be great!

**STEWY L** · 29-03-2010,09:55 PM

Originally Posted by njek

My Passat has recently developed an annoying problem, in that it is losing coolant. However, it's all a bit weird...

I noticed the problem a week or so ago. I'd driven into work in the morning, with no problems. However, when I got in the car in the evening to drive home, the info display immediately told me to switch the engine off, and check the coolant. Pretty much all the coolant from the expansion tank had gone. I topped up with water, and drove home with no extra problems.

Since then, I've noticed that long journeys result in very little coolant being lost, but short journeys result in a lot of coolant being lost.

Does this make sense to anyone?

The coolant is dripping from the front of the car, from the lower lip of the bumper. I've tried looking at the radiator, but can't see anything obvious. Next step would be to remove the bumper to take a closer look, but it's such a pain to do on the Passat, that it's a job which will have to wait until the weekend.

Tonight I have put a bottle of RadWeld in, left it idling for 30 mins, and it hadn't lost much coolant at all. The test might be tomorrow morning's drive to work.

Any help/advice would be great!

be careful with rad sealer.
if you add too much it can block the holes through the head gasket and crack the head. if it's dripping at the front bumper then it's a knocking bet that you need a radiator,or perhaps just a loose hose?
regards,
stewy.

**njek** · 29-03-2010,09:59 PM

Cheers for that Stewy

Any ideas why a long trip is OK, but a short trip isn't?

**STEWY L** · 29-03-2010,10:23 PM

Originally Posted by STEWY L

be careful with rad sealer.
if you add too much it can block the holes through the head gasket and crack the head. if it's dripping at the front bumper then it's a knocking bet that you need a radiator,or perhaps just a loose hose?
regards,
stewy.

Originally Posted by njek

Cheers for that Stewy

Any ideas why a long trip is OK, but a short trip isn't?

that's impossible--
to travel a long way,you must first travel a short way.

how can it get it's coolant back after you have dumped it on the road during the short journey?

regards,
stewy.

**njek** · 29-03-2010,10:33 PM

Lol...I get your point!

Put it this way - I drove from Bristol to Winchester, and lost no coolant. Whilst in Winchester (the next day) I drove from the car park to Halfords (about 5 mins) and, when I stopped the car, the coolant was dripping out like there's no tomorrow.

The same happened on the way back from Winchester to Bristol...no coolant loss.

I'm not imagining things...short trips result in lots of coolant loss...long trips result in very little coolant loss! Sounds bizarre, and is bizarre!

**STEWY L** · 29-03-2010,10:41 PM

the coolant still gets lost, it's just that over a longer period it gets hotter and the crack/leak seals up slightly and the coolant evaporates as it comes out(because it's hotter),and it doesn't drip onto the floor any more.
but it must be loosing it initially?
regards,
stewy.

**njek** · 29-03-2010,10:50 PM

I'm basing this more on the level of the coolant in the expansion tank, rather than the amount dripping.

After a long run (and after letting the car cool) the level is still where I topped it up to. After a short run, it's well below MIN by the time everything is cool.

**cazyp** · 29-03-2010,11:05 PM

I'll put money on the lower corner/s of your radiator rotten.
New rad. Don't mess with 'rad weld' stuff as said it can do more harm than good.
Get the undertray off and check out those rotten rad corners. Buy a new one, fit and flush all old coolant out of the system.
Refill with G12 coolant mix.
Job done.

Chipped2 · 30-03-2010,02:14 AM

My 2002 Passat TDi estate had a faulty rad. Dumped water suddenly when hot on a short journey. 800 mile journey no water loss at all. Again short journey dumped a load.

Dealer did pressure test all day, no Loss. Dumped water again on short journey when hot in traffic. Dealer did overnight pressure test, water on service bay floor. Rad had split in lower offside corner that only opened up when hot.

Get rad hot and look with torch at night at lower offside corner and you will possibly see the water glistening. Believe rads were faulty. Mine was replaced under Warranty.

**snapdragon** · 30-03-2010,11:57 AM

My radiator leaks from time to time, especially if disturbed but seems to heal, and is covered in the leak point near the bottom with a 5mm layer of pink dried G12+. It makes me wonder if the VW coolant contains a leak sealer (seeing as VW cooling systems are so prone to leaks anyway it would make sense)