Oh No! Heater matrix leaking?

[tofufi]

Originally Posted by Laird Scooby

There's a fairly simple reason i'm dubious about the vent in the kick panel Eric - i've never seen one do that in the UK. While you are lifting the carpet, you can check it though as you need to remove the kick panel trim, it's only one or two screws and then a tongue in a slot to slide out. You'll see evidence of the water coming in if that's where it's getting in.

I've just re-sealed one of mine as it seemed to be leaking

[Laird Scooby]

Originally Posted by tofufi

I've just re-sealed one of mine as it seemed to be leaking

Thanks Jim, first one i've known of here!

[lnparry]

Originally Posted by ericbeaumont

Lee,

Drove forty miles at speed last night with the temp needle dropping to 11 o'clock above 40 and heater output reduced, but this morning the header tank was green to max.

Matrix theory
Sampled the carpet water in both front and rear and it tasted of not very much - a very slight salt flavour, but after all the carpets (though clean and only 105k) are 22 years old. The header tank was a different matter, and I had to go rapidly indoors and wash out my mouth numerous times (since then a glass of good sherry has cleared the rest). The green mix tasted of very acrid, not very sweet medicine and was strong. However, the fact that it tasted significantly different from the carpet water doesn't convince me that the two are unconnected: the strong header mix could stay in there for a long time without moving through the system (this is a guess).

Vent theory
Came across this link http://www.forums.turbobricks.com/sh...d.php?t=341184 which explains how a vent in front of the nearside door hinge and behind the kick panel can fail and flood carpets, so that's worth exploring.

Sunroof theory
Poured water down the front exit holes in the sunroof gutter. Nearside came out of a drain hole two feet from the front nearside door hinge; offside came out of a drain hole one foot from the door hinge. Seemed to come out alright. Couldn't see the rear sunroof drain holes, but apparently pipes lead to the rear of the car.

Current optimism leads me to hope that the vent hole is flooding the carpets and that the temp gauge drop is the result of a dodgy thermostat or gauge temp sensor.
Have you summoned the courage to replace your matrix?

Hi Eric,
I will leave things as they are (possibly throwing in some Radweld or similar as Dave suggests if things worsen) until it warms up a bit and then might bite the bullet.

I'm also debating if I should be looking for something a little newer as I have two other classics to look after and I run out of time sometimes to keep them all up to scratch. But then I see the 945 on the drive and it looks so sleek!

Hope your leak just turns out to be rainwater.

Good luck,
LeeP

[ericbeaumont]

Good idea, Lee; working on a car in this weather is no fun, though the matrix seems a lengthy and awkward Meccano job rather than techno complexity.

I can see your dilemma with three classics to deal with, but if you need a stylish load-lugging cruiser with heated seats that lasts forever, can the others compete?

Reckon my two-part problem has light at the end of the tunnel (and it's not a matrix coming the other way) but I'll report the resolution in due course.

BW,
Eric.

[martin calva]

Originally Posted by lnparry

(...)
Has anyone replaced a heater matrix before as a first timer and is the job as horrendous as it looks or is it just a matter of methodically ploughing on and getting there in the end? Any tips would be appreciated.
(...)

I replaced the heater matrix on my V90 (with air con) during the past summer, as a first timer. I think that car may be the worst of all 700/900 models for changing the heater matrix.

Here is what I'd suggest:

- There are several accounts of how to do it on the internet (one somewhere in this discussion group). You should track these down and read them in detail several times. I would say that, for a first timer, it would be verging on the impossible without these accounts.

- The worst aspect (with the V90) is undoing about 12 screws around the heat exchanger that contains the radiator, three or four of which are almost entirely inaccessible. With perseverance, working by feel, using a flexible drive, they can eventually be undone but it might take a morning or longer to undo one or two of the screws. The screws (from memory) are 5.5mm hex head. It's worth buying several 5.5mm hex sockets as, when a socket drops out of sight behind something, you don't want to have to spend a morning trying to retrieve it. It's doubtful that you will find 5.5mm sockets at the local DIY store and you don't want the work to come to a halt while you wait for sockets to arrive via mail order.

- For replacing these screws, you can super-glue each screw into a socket. You can then put it in place without it dropping out of sight never to be seen again. Once the screw has been screwed home, the super-glue joint can be broken easily.

- Even when these screws have been undone, you will need to separate the parts which are glued together with a black tar-like sealant. I found that an old steak knife was useful for this job. White spirit is good for removing the tar stains which seem to finish up all over the place.

- You will need plenty of clean space to store the parts you remove. That will be almost all of the interior of the car, panelling, seats (front and rear in my case), ducts, radio, centre console,... I used the guest bedroom.

- You will also need plenty of working space on each side of the car, for removing the seats and for working with your head under the dashboard and your legs out of the doors. Don't attempt it in a one-car garage.

- Use a large sheet of cardboard to label each and every screw you remove. This is important. If you don't do it, reassembling the car will be a nightmare.

- The carpets and plastic foam from under the carpet will be saturated with coolant. To wash them out, put them in the bath and tread them all over several times, fresh water each time. To dry the foam (at least for the V90) will be difficult and will take a very long time. I was fortunate - a week of heat wave 30°C hot sunshine got them dry.

- You should count on taking two weeks to do the job if you work at my speed. If you work at it eight hours a day, six days a week, it may take less than two weeks. Don't put yourself under a deadline by requiring that the car should be back on the road by some particular date. The job may seem everlasting but it will eventually be done (unless you abandon it, as I can understand someone being tempted to do).

Good luck, if you decide to do it.

[lnparry]

Originally Posted by martin calva

I replaced the heater matrix on my V90 (with air con) during the past summer, as a first timer. I think that car may be the worst of all 700/900 models for changing the heater matrix.

Here is what I'd suggest:

- There are several accounts of how to do it on the internet (one somewhere in this discussion group). You should track these down and read them in detail several times. I would say that, for a first timer, it would be verging on the impossible without these accounts.

- The worst aspect (with the V90) is undoing about 12 screws around the heat exchanger that contains the radiator, three or four of which are almost entirely inaccessible. With perseverance, working by feel, using a flexible drive, they can eventually be undone but it might take a morning or longer to undo one or two of the screws. The screws (from memory) are 5.5mm hex head. It's worth buying several 5.5mm hex sockets as, when a socket drops out of sight behind something, you don't want to have to spend a morning trying to retrieve it. It's doubtful that you will find 5.5mm sockets at the local DIY store and you don't want the work to come to a halt while you wait for sockets to arrive via mail order.

- For replacing these screws, you can super-glue each screw into a socket. You can then put it in place without it dropping out of sight never to be seen again. Once the screw has been screwed home, the super-glue joint can be broken easily.

- Even when these screws have been undone, you will need to separate the parts which are glued together with a black tar-like sealant. I found that an old steak knife was useful for this job. White spirit is good for removing the tar stains which seem to finish up all over the place.

- You will need plenty of clean space to store the parts you remove. That will be almost all of the interior of the car, panelling, seats (front and rear in my case), ducts, radio, centre console,... I used the guest bedroom.

- You will also need plenty of working space on each side of the car, for removing the seats and for working with your head under the dashboard and your legs out of the doors. Don't attempt it in a one-car garage.

- Use a large sheet of cardboard to label each and every screw you remove. This is important. If you don't do it, reassembling the car will be a nightmare.

- The carpets and plastic foam from under the carpet will be saturated with coolant. To wash them out, put them in the bath and tread them all over several times, fresh water each time. To dry the foam (at least for the V90) will be difficult and will take a very long time. I was fortunate - a week of heat wave 30°C hot sunshine got them dry.

- You should count on taking two weeks to do the job if you work at my speed. If you work at it eight hours a day, six days a week, it may take less than two weeks. Don't put yourself under a deadline by requiring that the car should be back on the road by some particular date. The job may seem everlasting but it will eventually be done (unless you abandon it, as I can understand someone being tempted to do).

Good luck, if you decide to do it.

Hi Martin,
Many thanks - that is a really useful set of comments and suggestions.
Best regards,
LeeP

[lnparry]

UPDATE

Hi everyone, update on my heater matrix issues below.

The weather has been so bad of late that I couldn’t work outside to strip the old matrix out but had to continue using the car. I wasn’t losing a lot of water but was fed up with the windows fogging up with greasy vapour on a regular basis. So, I took the plunge and tried K-Seal.

I know there are mixed opinions on this and the potential risk of clogging up waterways, so I took the following precautions:
• The instructions on the bottle says it will treat something like 22 litres, about double the coolant capacity of a 940 so I only used half of the bottle.
• I drew off about 2 litres of coolant through the expansion tank using a syringe and narrow bore tube to pass along the hose that exits the bottom of the expansion tank and mixed the K-Seal with this. I was trying to pre-dilute the K-Seal before it went into the system.

Within a day my windows stopped fogging up and the leak appears to have stopped judging by the bundle of kitchen roll I keep under the heater to catch drips. Coolant level appears static, engine temperature spot on and heater nice and toasty.

I realise that I only did this a week ago and not trying to suggest that this is a permanent fix (although there is a post on here of someone getting a 5-year fix using K-Seal) just passing on my findings in case it helps others. Will keep you posted.
Cheers,
LeeP