Heater coolant leaking into passenger footwell (Mk 1 F-reg)

[alex cox]

Happy Xmas,

Over the past few months I've been having some brown sticky liquid leeking into the passenger footwell. Finally I've had some time and removed the glove box and panels and got in to the heater unit. On start up a small pool of water/sludge forms in the space just above the control lever arm and gets incrementally worse as you increase heater air flow and temp leading to a leak to the floor. I've lost about a litre of coolant in the last few months and seems to be getting worse (probably as it's got colder).

Has anyone else had this problem and do i need to replace the unit. I was planning on draining and flushing the coolant system, is this worthwhile to help stop the leak

Any help would be much appreciated. Thank you very much.

Alex

[PW@Woodsport]

hi alex,your heater matrix has a hole or crack in it...it needs replacing,a total nightmare of a job,about 4-5 hours for a competent mechanic...probably one of the worst jobs to do on a mk1! There is a quick way to stop it leaking,if you take both rubber pipes off the matrix in the front compartment and join them together (or join the head heater housing to the thermostat heater housing in the engine bay) it will bypass the matrix until you get it fixed,note you wont have a heater though,only cold air.

There is a little 12v electric heater available from kit car suppliers that might help you out in the short term but the only real answer is to have the matrix changed.

[Lauren]

For a temporary fix if the hole isn't too big you could try putting in some 'rad weld' as its cheap and simply a matter of pouring it in.

This may well fix it permanently, though at the very least if it stops the leak you will still have an operational heater at least.

[PW@Woodsport]

No way! under no circumstances would i use rad weld on a mk1!!,yes it might temporarily fix a small leak in a matrix or radiator but it also gums up everywhere that you dont want it to....totally dreadful stuff! blocks thermostats,blocks the waxstat waterways in the throttle body and finishes off a poorly flowing already silted up radiator....rad weld should be banned in my opinion! the only professional way to cure a leak is to replace the faulty part,the only thing worse than rad weld is cracking an egg into the system...to add it only ever serves as a temoporary fix,a mk1's cooling system is under pressure and it wont be long before it blows again.Worst stuff ever invented and only for the lazy amateur! Id only ever use it to get me home in an emergency,and even then id be wary.Just replace your matrix,job done.

On a side note theres some stuff on ebay claiming to fix a blown head gasket,similar type of crap...im sure it wont be long before we see,instant crank bearing mate or instant clutch regrower!

[crazylegs]

sorry to add to the bad news but pauls right .i cut up a mk1 last summer after stripping it completely. the heater matrix must be one of the first things put on to the car.there is NO easy way to get it out.a mate,jinxy,had a matrix problem at the time and we were looking at all the possible ways round it.we could not see any way but a major dismantle job.i expect you have checked all the hoses but have another look you never know.
Rad Weld...Laurens been at the sherry.

[spudgun]

I know I'm gonna get my ar$e chewed for suggesting this, but there is product we used on a mates car, which did work, and comes highly recommended if you trawl the webs forums.
I will start off by agreeing with Paul and Kev about radweld, that stuff is total sh1te. I wouldn't put it in any car, not even my 20 quid metro.
The stuff we used was called Cargo metallic seal-up, and to be fair it did what it said on the tin, so to speak.
Its a lot more complicated to use than the just chuck it in and forget stuff, like radweld, but was worth the effort.
While looking on the net to find out a bit more about it, I came across a miliatry report on it, which I thought, added some weight to its credability, and demon tweeks flog it as well, and although there are expensive, there not a company I would consider flogging rubbish.
Anyway over to you

[reggie]

If you're planning on doing the swap yourself and need to get hold of a matrix, I could probably get you one quite cheaply and depending where 'South' is I may even be able to drop it off for you! None of that postage lark.

[crazylegs]

on a similar note to reggie if you want the hassle of taking one out i have a part stripped car .you can have it for free the advantage being you dont have to be delicate a crow bar will remove the dash! you might get some idea of how to get it out, the car is going soon any way. i`m in Woking if its easier.