Heater valve/matrix replacement

[capri_rob]

Noticed a drip into the footwell on the passenger side today running down the centre console right under where the heater valve is so I assume it's knackerd or well on its way.

Is this as big a pig to change as it looks ? And is it likely to need a matrix too ? I am guessing that new ones from BMW are stupid money but as the newest used ones are at least 20 years old is fitting a used one pointless ? Any OEM aftermarket parts available ?

A walk through guide on how to change it would be useful - please don't tell me the whole heater box has to come out

[daimlerman]

Never had to do this,Rob,but I'm given to understand that the matrix 'just' slides out into the footwell.
I'm told that the valve is a similar job,there are two O rings on the valve,these are known to cause leaks,may pay you to pull it to bits before buying anything?

[Supafly]

I've done the o-rings in the valve. They're cheap from the dealers but the job is fiddly, from what I can remember it was difficult to get a socket on the nuts/bolts, and with a spanner it was impossible to get more than a few degrees to turn. I cut down a spanner (8mm I think, although it was a long time ago) and was able to get the job done.

[capri_rob]

The valve works in that when you turn the control knob it adjusts the temp but until I pull the console out of the way I'm not sure where it's coming from.

I need to get the console out then get it running on a dry day to pinpoint where it's coming from before I buy any bits.

Just read how to do it in andyboys book - sounds like fun

[Brianmoooore]

The valve does NOT adjust the temperature of the heaters output, in spite of what it says in Everet's book, except in the 0.001% of E30s that were fitted with climate control.
The valve is closed when the temp. dial is at full cold, but when the dial is moved a few degrees off of its stop, a switch closes, which applies 12 volts to the valve, which opens fully and stays open for the entire rest of the temp. control's range.
The valve's purpose is to ensure that on the full cold setting, there is absolutely no heat emitted from the heater.
You can get enough access to see what's happening simply by removing the inspection panel above the glove box, followed by the one to the right, but the rear and centre consoles have to come off to change the valve.
The only fixing that's difficult to undo is the small self tapper that's hidden behind the bracing strut for the brake linkage to the transmission tunnel (only fitted on RH drive E30s from mid production). Replace this with a hex. headed screw if you ever intend to remove the valve again.
The small bolts holding the valve that are facing the bulkhead are undone from the engine bay by pushing a 1/4 inch socket on an extension bar through the rubber grommet.
It's very unlikely that the matrix needs replacing. They do occasionally fail, but I've never had to change one yet.
Lastly, make sure that your coolant pressure cap has been replaced under the 1997 safety recall. The originals can cause the valve to fail.

[capri_rob]

Thank you Brian.
From your description the valve does appear to be working as with the control on full cold there is no heat at all but as soon as you move it heat does start coming through.

In your experience do the valves themselves leak or is it just the o rings that fail ?

Apart from speaking to bmw is there a way to see whether the coolant cap recall was done by looking at the cap itself ?

[darkchild]

The replacement caps have a yellow base iirc Rob.

[Brianmoooore]

It's the valve that usually fail - the rivets holding the two halves together pull through the plastic.
All the replacement caps that I've seen that I know have been replaced have had a yellow base, but allegedly there is also a version with a black base.
Your dealer will tell you from the VIN if a new cap has been fitted, and if not, should fit a nice new free one for you, but even if a replacement was fitted back when it should have been, it may not still be there now, of course.

[satvir]

I called up BMW and ask about that exact issue, and the lady on the other was very vague.

"There has been no recall on your vehicle" is all I got out of her, I was trying to ask weather there was a recall....and my car hadn't been fitted with the new part. I just got the same answer.

Very confusing think it may just be easier to buy a new radiator cap from BMW.

[Brianmoooore]

Call her back and quote the reference number on this: http://www.dft.gov.uk/vosa/apps/recalls ... =Blank&tx=

One of my pet hates is people who either don't know their job, or clearly do, and try to fob you off. Just like my son in law, who went to the dealer about four years ago to see if he could get his E46's boot floor repaired for free. "Never heard of this happening before, sir"

[satvir]

haha nice one. Will give it a try later this week!

[salam0506]

Hi Guys, read through the post and I have the same problem I think. I have only had my e30 for a few months and havent actually use to as it is for a project but the only times I did start it up I had steam and water shooting out on to passenger footwell.



So that is where the water and steam is coming from - do I need to drain coolant out from the radiator end first and then dismantle and change the o-ring is it? What exactly is the part called so I can ebay it or go to dealers.

[capri_rob]

Just had all the trim out of mine and I have exactly the same issue. Mint. Any tips on how to get it out without filling the footwell with coolant when you undo it ?

[Jona1971]

The inlet is at the top of the matrix, very little came out of mine (about a cup full).

[Brianmoooore]

Best way to avoid coolant stains on the carpet is to disconnect both hoses under the bonnet, then connect a garden hose to the bottom stub, and flush the coolant out. Any spillage will then just be plain water.

[capri_rob]

Excellent thanks Brian will do.

Am I going to have to drain and refill the whole system afterwards or is it just a case of putting a bung in each of the under bonnet hoses to keep most of it in ?

[Brianmoooore]

Hoses are pretty much the highest point in the cooling system anyway, so there isn't going to be much come out. I usually tie them to the screen wiper spindle with a bit of string.
Watch out for air locks when you refill. Heater should start producing noticeably warm air within a minute of starting the engine.