Radiator Drain Plug 1995 Audi 80 TDI

**jacksticks** · 14-01-2015,10:07 AM

Morning all.

Purchased an M reg Audi 80 TDI at the weekend. Went to check the coolant yesterday and found a rather dirty and brown sludgy coolant tank, i couldn't see any oil or smell exhaust gasses so I whipped the bottle off and drained and tried to clean the best I could. I wanted to drain the radiator but I couldn't seem to find a drain plug anywhere. It also looks like the car is running at too low a temp, about 50 on the temp gauge so I am thinking stuck open thermostat? Is this easy to change as I noticed there are no Haynes books on this model?

Anyway any help greatly appreciated.

Thanks.

**Doctle Odd** · 14-01-2015,01:06 PM

There should be a drainage tap on the bottom left of the radiator as viewed from the drivers seat. If not just take the bottom hose off. Thermostat is pretty easy to change. Haynes manual for an early MK3 golf will cover most of the mechanicals. Gearbox, driveshafts etc, an A4-B5 manual will cover most of it.

**jacksticks** · 14-01-2015,01:16 PM

Thanks for that, that is great to know. Looks like there is some kind of shield or drip tray? under the engine bay that i will need to remove if i were to drain the radiator. Regarding the stat I am getting hot air in the cabin no problem but as mentioned the temp gauge will only go to 50...would a failed stat cause this?

Thanks again.

**Doctle Odd** · 14-01-2015,01:29 PM

Originally Posted by jacksticks

Thanks for that, that is great to know. Looks like there is some kind of shield or drip tray? under the engine bay that i will need to remove if i were to drain the radiator. Regarding the stat I am getting hot air in the cabin no problem but as mentioned the temp gauge will only go to 50...would a failed stat cause this?

Thanks again.

It might be the CTS (coolant temperature sensor) Youre going to have to invest a few pennies in diagnostic equipment. If you have a laptop https://www.gendan.co.uk/product_VAGUSB.html you'll also need one of http://www.ebay.co.uk/itm/Brand-New-...item19ceec1391 these but not an ebay one

**zollaf** · 14-01-2015,02:21 PM

if you have toasty air in the cabin then it could be the cts or it could be a dry joint on the dash. its easy enough to remove and strip, then touch up most of the contacts. theres a 3 legged diode thats a main culprit. stat is at the end of the bottom hose where it joins the water pump, quite tricky to replace with the pas pump bracket in the way. far easierto remove this. as doc says, there is a drain in the passenger side corner of the rad.

**jacksticks** · 14-01-2015,02:46 PM

Thanks very much. I suspected the CTS after reading a lot of people had similar problems. This looks like something I could change myself, even if I am a rookie? Regarding the radiator i can't remove the bottom engine bay cover safely as I can't get under the car so will have to take it to my garage for them to drain. I have bought a new expansion tank as well as mine is still caked in brown rusty sludge which I couldn't clean off so they can fit that. Would it be best to change the CTS at the same time or could I do this before the rad flush etc?

Loving the car, I am still not 100% sure the gasket isn't blown as the coolant was really brown, almost black when I drained yesterday. I refilled and put fresh water in and ran the car for 20 mins before the brown sludge came back but I am presuming this is still circulating around as I couldn't flush the radiator. My worry is, I change the CTS and it then starts to gauge proper temp and registers over heating due to a gasket fault. There is no milky like substance though and I can't smell gasses so fingers crossed it is just years of crap in the pipes.

Cheers

**zollaf** · 14-01-2015,02:50 PM

maybe best to bite the bullet and do the head gasket. if the coolant is that rusty then its long overdue a change so may have eaten the gasket anyway. they are really easy to do.

**jacksticks** · 14-01-2015,02:53 PM

Really, isn't it labour intensive? I only paid £650 for the car so would it be worth it?

Cheers

**zollaf** · 14-01-2015,02:55 PM

cheap car. takes about 3 hour to get the head ready for a skim and a bit more to rebuild. cheap if you are doing it yourself and you can remove the rad to do it and fit a new timing bet kit. i would, or rather did when i bought mine, just as a matter of course on a 300,000 mile engine. but i do it for a living and for fun.

**jacksticks** · 14-01-2015,03:08 PM

Yeah, unfortunately I wouldn't know where to start. If it was head gasket wouldn't the engine over heat even if the CTS was faulty? Also wouldn't the coolant boil?