So I took the dash out, broke the damn wiper stalk
. Anyway, I got the matrix out. A long winded job, but nothing difficult about it.
It looked ok to me so I figured I'd try to descale it. I poured Toilet Duck into it and left it in a bucket overnight. Soon after I put it in the bucket it started frothing an unpleasant green goo.
Next day I flushed it thoroughly, removing lots of horrible sludge as I did this. I gave the front radiator the same treatment while I reassembled the dash and flushed the engine out with a garden hose.
The engine seemed clean however I got more sludge out of the radiator.
Now I have a great heater again, its gets warm quickly and I need to turn the heat down after a few miles.
Strange, but the temperature gauge seems to read a little warmer than it used to, but that's probably me just keeping a closer eye on it.
With hindsight all I needed to do was fill up the heater in situ, let it brew overnight and flush it through. But calcium remover isn't a friend of aluminium and I didn't want an interior stinking of toilet cleaner!. If I ruined the matrix it would have been no big deal, I'd need a new one anyway, but I got lucky.
So anyone with a lukewarm heater might like to try this, but I won't guarantee you won't wreck the matrix.
Roger.
