Using coolant in T5 Tdi

[Ivo]

Hi guys, I was driving on some country roads this weekend 20-50kmh average speeds. Got to our destination without a problem. Went out to the car the next morning, started it up and a warning came up saying "coolant low" I checked the reservoir and it was down about 20mm below the minimum mark. I topped it up, and warning message stopped. I drove about 40km on more dirt roads, parked the car for a few hours while I did a mtb race then drove back the 40km to where we were staying. Temp gauge was reading normal, loaded up the kids and gear and started to drive home. This time on tar roads average speed about 90kmh. The alarm and message came on after about 10 minutes. I stopped and check and the water was down again 10mm below the min line. I topped it and continued home at freeways speeds for another hour with no alarms or warnings.

Got home and checked again, coolant was down again about 5mm below minimum level. Dipped the oil but it did not show any signs of water. Temp gauge did not move off its usual mark of 90deg at any time.

I do not know the history of the car before I bought it at 85k it now has 160k on it. I'm thinking it could be a water pump failure but I would have expected the temp to rise. I have also heard of the seal that goes allowing coolant into the oil system.

What are your thoughts?

If its the water pump that has failed what will it roughly cost to fix? If its a the seal what will it cost?

[PeDiES]

the pump when it first starts leaking will be slow enough for the engine to steam the water and you probably wont see it till it gets worse.
thats only if your not seeing any leaks anywhere. The whole unit needs to be replaced, not just the seal unfortunately.

[IN2VWS]

Is it a 128kw motor?

[Ivo]

2005, 128kw.

[BrianJ]

If its leaking into the engine oil I believe you need to get it fixed urgently, because oil floats on water so the oil pump which picks up oil from the bottom of the sump will feed water to the bearings and your engine is history. The forums are littered with such cases, the first fault noticed is cam and followers badly worn, then turbo bearings mysteriously fail, and the list goes on.

Brian

[Ivo]

I don't plan on holding off with the repairs, will get it to the workshop tomorrow. I just wanted to get an idea of what it could be.

[mikinoz]

I don't plan on holding off with the repairs, will get it to the workshop tomorrow. I just wanted to get an idea of what it could be.

Good luck, at least you are taking it in before it is lunched!

[IN2VWS]

If you remove your oil filler cap, is there the white creamy crap in there?
A mate had it on his 128kw T5, it was the water pump at fault.

[Ivo]

Just checked under the cap, it does look a bit suspicious..... dark grey creamy gunge under there.

[Transporter]

You can test for the presence of the water in engine oil quite simply.
Borrow your wife’s or girlfriend’s iron for ironing the cloths, turn it on hottest setting and drop a drop of oil from the dipstick into the hot plate.

The rest is in here; Monitor Water-In-Oil with the Visual Crackle Test

See also my post http://www.vwwatercooled.org.au/f136...tml#post432884

remove 3 bolts that cover the water pump and check if the w.pump gear moves with the w.pump shaft, mine had to be bouncing of the gears a lot.

[Ivo]

Water pump is being replaced, hopefully have it back Wednesday.

[Rebuild]

Just checked under the cap, it does look a bit suspicious..... dark grey creamy gunge under there.

AFAIK,if you do a lot of short trips the gunge is normal.Even mine has a little.

[mikinoz]

Water pump is being replaced, hopefully have it back Wednesday.

I hope you come out of it not too expensively.

[Transporter]

AFAIK,if you do a lot of short trips the gunge is normal. Even mine has a little.

I also do mainly short trips and my oil cap looks normal. I mean short trips like 5km-8km but often only 2km stop for an hour or 2 and short trip home or to next job. You can always do a crackle test just to be sure your pump is not leaking. There is a small dia. hose at the back of the engine that will show some rusty deposit at the end. I think that many T5 AXD, AXE engines have a leaky water pump for some time before it is discovered; the coolant probably gets topped up during the scheduled service without investigating where it has disappeared. In the closed system there is no coolant lose to evaporation.

[IN2VWS]

Agree with Transporter.....AFAIK, there should be no gunge under your cap. Yes, in the old days of air-cooled VW's, this was normal, but not in a closed system.