Help please, Heater/thermostat problem

[SD1too]

Originally Posted by Cliff.Harding

Do I need a T4 diagnostic to find out water temp?

No, not T4 but instrument pack diagnostics as stated in my last post.

How do I go about checking that?

You select test 7.0 according to these instructions. Report back with the readings during varying road conditions and we'll take it from there.

Simon

[Cliff.Harding]

Right this is where we are now.
I took out the heater matrix and found it to be ok.
However I have so far been unable to reconnect the top pipe (i just can't get it together) has anyone got any suggestions?
I did the Plenum mod and yes there was water in it so thanks for the photo's Arctic.
I have been trying to get to the thermostat but after removing the inlet manifold bolts, there must be something else holding it in so I would be grateful for advice on how to get it apart I have the thermostat kit so can anyone help please?

[SD1too]

Originally Posted by Cliff.Harding

... but after removing the inlet manifold bolts, there must be something else holding it in ...

Now Cliff, are you asking about the inlet manifold chamber (black plastic moulding attached to the throttle body)? Or are you referring to a real inlet manifold which is bright aluminium, and one for each bank?

Simon

[Cliff.Harding]

Just a quick update on my progress.
I had some help from my son with this because I tried to check the heater matrix (big mistake) not only was there no problem with it but I couldn't fix the pipes back (good job my son was on hand and managed to do it.
We used the Keyhole method for replacing the thermostat that was family straight forward so now to fill it with coolant and fingers crossed no leaks.
How much water/coolant does it take by the way?

[SD1too]

Originally Posted by Cliff.Harding

How much water/coolant does it take by the way?

Cliff,

First of all, the factory filled cooling systems with a 50% concentration of OAT antifreeze. If you want to change to standard 'blue' antifreeze (not OAT) the manufacturer recommends flushing the cooling system because the anti-corrosion additives in OAT and standard 'blue' antifreeze are apparently incompatible.

Also, some members believe that OAT antifreeze at 50% concentration may have a detrimental effect upon 'O' rings in the KV6 engine. Although there is no direct evidence supporting this theory, a reduced concentration of 33% should still be effective (well, it has been in my SD1 for the past 25 years!).

Secondly, with a KV6 you must follow the MGR procedure for refilling as follows:

1. Apply Loctite 242 to first three threads of cylinder block drain plug. Tighten to 20 Nm.
2. Remove bleed screw from radiator bottom hose.
3. Remove bolt securing expansion tank and raise as high as possible (approx. 125 mm).
4. Fill cooling system keeping level at expansion tank neck until a steady stream of coolant is emitted from bleed screw hole. Fit and tighten bleed screw.
5. Continue to fill expansion tank until level reaches neck and remains static. Refit tank to body, tightening bolt to 5 Nm.
6. Press 'Econ' button to switch air conditioning off [this is to prevent the radiator fan from running continuously].
7. With expansion tank cap off run engine at 1,500 - 2,500 rpm, filling as necessary to keep coolant level just below expansion tank neck. When level starts to rise, fit cap.
8. Continue running engine at same speed until the radiator fan starts, then reduce to idle until it stops. [In practice this may not be achievable, in which case establish that the engine has reached above 90° by activating the IPK diagnostics.)
9. Allow the engine to cool for at least 30 minutes and top up the expansion tank no higher than the 'Max' marker. If this is not visible, remove coolant until it is. [In practice, topping-up will be necessary three or four times after a journey.]

You'll need at least 7.5 litres of coolant.

Simon

[Cliff.Harding]

Well I've done it it's all up and running again, it's now nice and warm in the car.
I took her on a run of about 80miles yesterday and she seems to be fine now.
Thanks to everyone who posted help it was invaluable.
I am going to have a look at the diagnostic today, will post findings when I have them.
Now all I need to find is the cause of the wet carpet in the rear footwell.
It does seem to be drying out, so as I have drained the plenum chamber could that be the cause of the problem?
My Son is an Audi master Tech and tells me they are always draining plenums, and they manifest themselves in many varied ways.

Could that have been the problem?

[carguy143]

Originally Posted by Cliff.Harding

Well I've done it it's all up and running again, it's now nice and warm in the car.
I took her on a run of about 80miles yesterday and she seems to be fine now.
Thanks to everyone who posted help it was invaluable.
I am going to have a look at the diagnostic today, will post findings when I have them.
Now all I need to find is the cause of the wet carpet in the rear footwell.
It does seem to be drying out, so as I have drained the plenum chamber could that be the cause of the problem?
My Son is an Audi master Tech and tells me they are always draining plenums, and they manifest themselves in many varied ways.

Could that have been the problem?

Edit: just clocked the date, sorry for the revival but I hope it helps others!
I'm glad you got your heater sorted. As your your wet rear carpets water could come in through the rear light seals, the side trims or even rear window surround.

Rik.

[biffa75]

Originally Posted by SD1too

Cliff,

First of all, the factory filled cooling systems with a 50% concentration of OAT antifreeze. If you want to change to standard 'blue' antifreeze (not OAT) the manufacturer recommends flushing the cooling system because the anti-corrosion additives in OAT and standard 'blue' antifreeze are apparently incompatible.

Also, some members believe that OAT antifreeze at 50% concentration may have a detrimental effect upon 'O' rings in the KV6 engine. Although there is no direct evidence supporting this theory, a reduced concentration of 33% should still be effective (well, it has been in my SD1 for the past 25 years!).

Secondly, with a KV6 you must follow the MGR procedure for refilling as follows:

1. Apply Loctite 242 to first three threads of cylinder block drain plug. Tighten to 20 Nm.
2. Remove bleed screw from radiator bottom hose.
3. Remove bolt securing expansion tank and raise as high as possible (approx. 125 mm).
4. Fill cooling system keeping level at expansion tank neck until a steady stream of coolant is emitted from bleed screw hole. Fit and tighten bleed screw.
5. Continue to fill expansion tank until level reaches neck and remains static. Refit tank to body, tightening bolt to 5 Nm.
6. Press 'Econ' button to switch air conditioning off [this is to prevent the radiator fan from running continuously].
7. With expansion tank cap off run engine at 1,500 - 2,500 rpm, filling as necessary to keep coolant level just below expansion tank neck. When level starts to rise, fit cap.
8. Continue running engine at same speed until the radiator fan starts, then reduce to idle until it stops. [In practice this may not be achievable, in which case establish that the engine has reached above 90° by activating the IPK diagnostics.)
9. Allow the engine to cool for at least 30 minutes and top up the expansion tank no higher than the 'Max' marker. If this is not visible, remove coolant until it is. [In practice, topping-up will be necessary three or four times after a journey.]

You'll need at least 7.5 litres of coolant.

Simon

Hi Simon,

Im having issue bleeding coolant system after the thermostat change.

In your point above where it mentions keeping the coolant tank cap off and topping up as required to keep the coolant level, level with the neck if the coolant tank.

Having raised the tank, opened the bleed screw and a steady stream of coolant coming through the bleed screw and placing the bleed screw back etc.

Lowering the expansion tank and topping up the tank so it's level with the bottom of the neck of the expansion tank, with cap off I find coolant just flows out constantly with the revs raised.
(Do I need to keep the revs raised until the thermostat opens or should coolant stop flowing out if the top of the coolant tank after a few minutes or something?)
I kept the tank cap off for around 10 mins and put the cap on.

Thanks
Rob

[SD1too]

Originally Posted by biffa75

... with cap off I find coolant just flows out constantly with the revs raised.
(Do I need to keep the revs raised until the thermostat opens ...

No Rob, "until the level starts to rise" is the official instruction. You're saying that this happened immediately on starting the engine?

Perhaps your filling and bleeding was super efficient. I'd be inclined to view the actual coolant temperature when driving and check the expansion tank level when the engine has fully cooled. I'd expect it to have dropped.

Simon

[biffa75]

Oh fair enough in that case and yes the level began to rise pretty much as soon as the engine was started, the level rise and began to flow out of the expansion tank. It did drop a little over the course of a few days, not a lot just needed a little top up.

Thanks for confirming
Rob