Leaking/Failed Water Pump

[gallaj01]

I was driving home from a weekend at the cabin in my 01 Jetta with 255K miles and 5 miles from home my coolant light came on. Usually a coolant light doesn't worry me too much on a high mileage car (thermostat housing, hard coolant pipe, various aging gaskets), but my experience is that when these sort of slow leaks occur the light/alarm only comes on once the car has stopped and the coolant level is steady. In this instance the light came on while traveling near 70mph after traveling over a road heave. I didn't see a bunch steam come out of the hood or a trail of coolant behind me, so I just drove the last couple miles home.

When I got home, I see that the coolant expansion tank was empty and noticed a steady drip from the belly pan. I put the car up on ramps pulled off the belly pan and started looking for the source of the leak. I check the usual suspects (tstat flange, hard coolant pipe, egr cooler) and none of them were leaking. I crawled under the car and could see coolant leaking from the bottom of the TB cover.

Popped off the upper TB cover and found this:

The inside was covered in coolant. I looked at the water pump and thought the sprocket might look slightly out of alignment, so I gently pried with a screwdriver: http://youtu.be/HxO2ejq4JOA

Looks like the water pump could have completely gone at any moment. I was so lucky it didn't completely go and take out the TB

My 01 Jetta TDI is due for its 3rd TB change in the next 5K miles. I had already ordered all the parts and was planning on due it the second weekend in August. Only trouble now is the garage, tools, and parts are all 250mi away. Looks like I should have done it sooner

So glad JasonTDI is only 15min away now that I live in Madison, WI. A big thank you to him for being available to tow my car to his shop and take care of the TB change this coming weekend!

 

[Bran Diezel]

Lucky!

I can't tell you how many cars I've found small ball bearings in the bottom timing cover only to call the customer with the bad news. Sometimes the motor isn't an interference and they get lucky. As close as our cars valve tolerance is you should prob buy a lottery ticket.

 

[belome]

Hopefully you didn't also cause problems from the overheat. Strangely enough, cars have these lights for a reason.

Guy at work just ignored his flashing oil light because he assumed it just meant the oil level was low... now he has a blown up motor. Kids these days.

 

[gallaj01]

Hopefully you didn't also cause problems from the overheat. Strangely enough, cars have these lights for a reason.

Guy at work just ignored his flashing oil light because he assumed it just meant the oil level was low... now he has a blown up motor. Kids these days.

I watched the dummy gauge for those final 5 miles, and checked the coolant temp with VCDS when I got home. As best I can tell the coolant temp never went above the normal range.

 

[mk3]

What brand was that pump that failed? ... of course keeping in mind this is just one data point.

 

[Jettascuba]

Coolant light will only come on once coolant is low, you can trust it on that. Once you car is out of coolant, the temperature sensor may not follow the temperature of the block, as air conduct heat slower than coolant to the sensor, thus your gauge may not indicate high.

The VW dealer did not replace my waterpump during its first 2 timing belt changes, and it failed like yours at 305 000km (the original one). I didn't know better, only learnt of TDI's after I joined here.

 

[jasonTDI]

It was a hepu. I did the belt last night after fetching the car. Tensioner was bent and ready to go as well. Lucky....