leaking heater matrix

Hi,

Whilst removing the old carpet from my cabby gti I found a damp patch right under the heater matrix.  Noticed a drip coming from the matrix casing as well and its definately coolant.

I've had a look at how to get in to the matrix casing so I can see where the leak originates from but not having much luck. Have removed the small metal clip on the bottom that holds the 2 parts of the casing together but something else is holding it together and I can't see what.

A guide of what I should be looking for would be appreciated.

Cheers

If you want to remove the heater matrix to inspect it there should be a removable panel on the left of the matrix housing, look for where the coolant feed and return pipes come through the bulk head disconnect these,x2 jubilee clips, then remove panel and slide matrix out gentle. Before you do this drain the coolant system or you will get wet.  

Cheers for the reply. Checked today and there were about 10 drips that had come from the matrix overnight. I did a bit of research and from what I found it looked like that it was a bit of a pest to fit a new heater matrix. I was under the impression that the dash or kneebar has to come out to gain access? Have ordered a new matrix today from veedubmachine for £19.54 delivered which seemed a good price.

Would help to remove lower part of dash just to gain more access and make things easyer but if you want to split the to halfs of the matrix housing then start by draining coolant then undo coolant feed/return pipes at matrix end then unclip heater control cables and then undo the four self tapers that hold the cover/grill that protects the blower and also secures the top of the housing to the car, this is located under the plastic scuttle tray under the bonnet. Bit of an essay all that   , can send pics if that helps?

I think I'm following what you mean!  I took the kneebar off earlier today but then ran out of daylight.I'll have a look 2moro and see how I get on. If I struggle some pics would be great. Cheers for the help

Need to add if you are taking the full housing out you need to remove heater ducts, there is one either side and just pull off, and disconnect the blower wiring which should be two connector blocks on left of housing. Fogot about these DOH!

Okdokes, cheers for that. Will have a go shortly when I get home from work. Update to follow...

Heater matrix removed. Had to cut the pipes as they wouldn't budge when I took the clips away. Have ordered new ones which weren't easy to find. Probably better to replace them anyway. Should be straight forward enough to it everything back together.

Thanks for the advice.

Euan

When you refill the coolant make sure the heater control is all the way across to hot this will allow the coolant to get around the matrix, dont need the blower on. No worries for the help glad you got it sorted  

Phil

Just got the same problem, and found out The same way :-)
I would like soms photos to guide me though, if you still have them?

just look in the passenger footwell, it'll become obvious.

no need to remove anything at all on a cabrio its right there. small box shaped cover to unclip then theres your matrix. as the OP found the hardest part is getting the 2 rubber pipes off the matrix as clearance is tight and they can be well stuck

When I changed mine recently, I was also replacing the heater valve and the pipe connector on the other pipe from the matrix. This meant I could pull the pipes off the matrix by pulling them from inside the engine bay, while they were disconnected. Alos made reconnecting them easier by pushing them onto the new matrix. Hope this helps.

Thanks for the tips, I'll give it a try this weekend while I wait for the parts.
I'll report back with the progress 

rubjonny said

just look in the passenger footwell, it'll become obvious.

no need to remove anything at all on a cabrio its right there. small box shaped cover to unclip then theres your matrix. as the OP found the hardest part is getting the 2 rubber pipes off the matrix as clearance is tight and they can be well stuck

Hi John - Don't suppose you have a picture of the clips I need to undo at all do you?

I've noticed the coolant leaking onto my carpets and need to sort before I put the new ones In that are sat in my lounge! I can see the two pipes coming from bulk head, and a rectangle shaped plastic case covering these? How does that 'pop off' ??

sorry there are no clips, just that plastic cover over the end of the matrix you have to pop off reveal the matrix and the hose clips to it.  no special method, just give it a tug and off it will come

Just be carful taking the cover off as one of my clips broke off last time I took mine off.
A bit of old credit card cut to shape then super glued on the back of both bits to hold it worked for me as you will never see the back.

Evening gents,

I managed to pop the cover off this evening, so I assume all I need do now is;

a) Drain coolant system
b) Remove hose clips in picture
c) Pull heater matrix out (?)
d) Replace with new & re-attach hoses

My unit looks in pretty bad shape to be fair, not surprising it's leaked !!

no need to drain the full system, just disconnect the 2 coolant hoses to matrix in the engine bay and angle them down to drop as much coolant as you can.

jack the car up as high as you can from driver side rear to try an encourage some to come out of the matrix, but due to the design and the way it comes out you'll want a bucket under it!

if you have a couple suitable size bungs to hand you can block off the matrix outlets as you pull the pipes off, that'll minimise coolant loss.  or since its already been leaking, I guess you wont care too much about a bit more

rubjonny said

no need to drain the full system, just disconnect the 2 coolant hoses to matrix in the engine bay and angle them down to drop as much coolant as you can.

jack the car up as high as you can from driver side rear to try an encourage some to come out of the matrix, but due to the design and the way it comes out you'll want a bucket under it!

if you have a couple suitable size bungs to hand you can block off the matrix outlets as you pull the pipes off, that'll minimise coolant loss.  or since its already been leaking, I guess you wont care too much about a bit more

Cheers as always mate - going to give this a whirl tomorrow! Wish me luck

So I failed miserably at this yesterday!!

I could not for love nor money get the coolant hose to come away from the pipe in the engine bay. Granted access is tight, but I'd need the worlds strongest man to get these out!

Any ideas at all?