How to change VR6 thermostat

[Nick_Micouris 0]

Hey chaps

My VR has been running real hot on motorways with the fan on permanently! I have been trying to find exactly where the stat is and I am failing!

Thought it was near the main water pump on the aux belt near the alternator etc but it cant be....

The other place I looked was beneath the coil pack and near the aux pump.

I ended up prising a plastic covering off 3 sensor plugs and think I have found it... Can anyone tell me where it is and if indeed I am in the right place.

Incidentally I cracked the covering (part357972279) is this covering essential??

Okay! Thanks

Nick

[Kevin Bacon 5]

No the cover isn't essential but it's there to keep water off the sensors. And that is precisely where the thermostat lives...inside that plastic housing.

 

Not a particularly pleasant job but doable inside 2 hours. Remove the coilpack and you'll see what needs doing and where all the bolts are etc.

 

When you refill with coolant (G12+ from the dealer), fill via the radiator top hose and not via the expansion tank.

 

K

[Nick_Micouris 0]

Hi Kev

Thanks so much! Glad I found the right place...

Is it actually underneath (upside down in situ) where the electrical plugs would go?

Also - if I flush the system - where should I plant the hose and which pipe should I diconnect as an outflow for the old coolant?

Does the coil pack just bolt on?

Should I change the plastic housing for the thermostat as well as the seal? Any other tips?

Cheers :)

Nick

[Ice White Socks 0]

Should I change the plastic housing for the thermostat as well as the seal? Any other tips?

Not many people seem to able to replace the thermostat without cracking the housing- I would get a new one before you start the job

 

Mike

[Kevin Bacon 5]

Hi Nick

 

Yeah you found it OK :wink:

 

The thermostat is sort of lower down and round the side of the engine inside the housing, if that makes sense??

 

I would change the housing as well as the thermostat as the housings are a known weak point. They crack or bend causing coolant loss, so you may aswell do the lot for the sake of £25 + the stat.

 

Yep the coil pack just unbolts. 4 long allen bolts with a 5mm hex head. You'll need to remove the plastic cowling that's above it first, and to do that you need an 8mm spline key, or maybe an allen key if it fits.....failing that I've got them off with a screw driver before!

 

To drain the coolant you pull the rad bottom hose and undo the block drain screw which is on a long plastic transfer pipe on the front of the block. It's above and to the left of the oil filter, about the size of a new 10p.

 

Not sure if you'll be able to drain it into a container as it gets everywhere.

 

To refill, pop the bottom rad hose back on and the drain plug, then undo and pull off the rad top hose and the expansion cap.

 

Mix up your G12+ with some water to a 70 Water 30 G12 ratio and then pour it in through the top hose until you see fluid appear in the expansion tank. Keep pouring until it starts over flowing out of the top hose. Replace the top hose and secure. Run engine until the level in the expansion tank rises.....as it's rising, quickly screw down the cap.

 

Take for a 20 min drive.

 

Top up to max level and no higher in the morning and you're done :lol:

 

K

[Nick_Micouris 0]

Nice one guys! Will get the parts and do this on monday. 8)

Nick

[Nick_Micouris 0]

Oh - just another thing :oops: - when we are talking about the housing do we man the part with the space for the 3 plugs/sensors or the elbow. Or both!

Anyone have the part number/s

[Kevin Bacon 5]

It's all one unit. You just take your Yellow, blue and black sensors out of the existing housing and transfer them to the new one. Might be worth investing in a new seal for each while you're there.....

[corradovr6sc 0]

It's in 3 pieces:

021121117A

[Kevin Bacon 5]

The stat goes in the bit with the 3 sensor holes. The bit on the left is the stat cover and the bottom bit is the attachment for the transfer pipe.

 

All you need is the bit with 3 holes if it's bent/cracked. I didn't need to replace any of them when I did my stat, but you can if required.

 

K

[Nick_Micouris 0]

I actually got the 3 separate piecesy. Would it be logical/easier to assemble the thermostat elbow with Stat and seal inside and also the the transfer pipe with seal, so that the 3 pieces become one before fitting? Will it make it easier in the long run do you reckon?

[Kevin Bacon 5]

I actually got the 3 separate piecesy. Would it be logical/easier to assemble the thermostat elbow with Stat and seal inside and also the the transfer pipe with seal, so that the 3 pieces become one before fitting? Will it make it easier in the long run do you reckon?

 

Yep, a lot easier. Clean up the block face with some emery cloth and fit a new seal. Don't use any sealant gunk as it sometimes makes matters worse!

 

Test the stat in a glass jug with some boiling water first as I've been given a duffer before.....you should see it open almost instantly when you drop it in.

 

Then you slide the assembled housing onto the transfer pipe and then it should all be lined up on the block quite nicely then.

 

K

[Nick_Micouris 0]

top stuff! thanks - thought that would make sense :)

[PhatVR6 0]

See that nipple thing on the edge of the stat? that needs to be at the highest point. it's a valve to let air locks through.

 

cheapo t stats don't have that valve, and are a pain in the ar5e.

[Nick_Micouris 0]

nice one - thanks! By "highest point" I take it you mean nearest to the hole in the incoming pipe? doing the job today :)

[PhatVR6 0]

the housing is on a tilt. air rises to the top of course. so position it where you think that the air can get through that valve best.

[Kevin Bacon 5]

Not heard of any of that before. I just slapped my new one in (VAG), poured in the coolant down the rad top hose and off I went. Coolant level hasn't changed 9 months later.

 

K

[PhatVR6 0]

I bought a new (cheap) thermo stat for mine. I eneded up taking it out on the side of the A66 on my way up to scotland because the f*cker wouldn't open.

 

if the secondary water pump fails you;ll get air locks in the head too. it's there to help circulate water through the head. I wire mine so it's running all the time the engine is.

[dr_mat 0]

Thought the aux water pump *was* running all the time the ignition is on?

Mine does!