Radiator Leak

There are no photos with this post. the best horror stories are left to your imagination. 

My radiator leak has been persisting and so I took it off the car again to examine and/ or get pressure-tested. If needed, a re-core would not be cheap, but my friend Peter had offered me an alternative radiator at a very good price. He'd had it re-cored (with three cores) but hadn't used it. It's off a later DS, so the small M5 sized threads for bolts for the bracing bar and fabric hood are different to those on my car, but that's a minor point.

I collected the radiator from Peter and, since I was taking my radiator to be pressure tested, decided to take his along too. Both radiators came back with reports of 'no leaks found'? You might think I'd have been happy - but I was sure that was wrong for at least one of the two!

At home I tried to carry out some more testing of my own. Blocking off the top and bottom inlets/ outlets with offcuts of thick polythene sheet and jubilee clips, I filled the radiator, blocked the overflow with my finger and blew furiously into the filler cap hole. It appeared only very slowly but - as suspected -  I began to see the outcomes of a tiny weep from somewhere within the dark recesses of the radiator. Wherever it was, it was VERY small at the moment.

Based on where the water was appearing, the leak seemed to be from where one of the zig-zag vanes was soldered to one of the outer tubes and - if so - it seemed fairly accessible. I decided to have a go at repairing it. I'd done similar work on an old heater matrix so thought it was worth a try. 

It wasn't. I tried to apply some solder. I heated the area and the 'vane' metal was so thin that it turned to ash... Also, the core tube was so thin that the small hole became a bigger hole - meaning a repair was now impossible...... Never mind. it was Just one core on the outer edge of the radiator. i could just plug that core with solder and ignore it. 

I addd heat and tried to solder again. It got worse. I think I was kidding myself as the work area was inaccessible and becoming quite dirty by now - with little chance of getting solder to stick. Instead, the heat had caused a hole in the core next door.... and there was a growing absence of 'vane'.....I tried a third and last time.  By the time I had finished several cores, several rows deep, had sections missing.

I had to finally concede that I'd well-and-truly killed the radiator.  I'm very pleased to say that there is no photographic evidence of this but trust me - it wasn't a pretty sight by the time i'd finished. It looked like the radiator had been hit by a small meteor.....

The obvious solution was to fit Peter's radiator, but I reasoned that I would then be without a spare if his also turned out to have so leak. At this point I could have just fitted Peter's and tried it. Or I could have taken it to be pressure-tested a second time. But no. Instead I did the 'walk-of-shame' back to my radiator shop with my dead radiator and confessed what I'd done. It was a costly lesson. Yes - the radiator leaked anyway but I ended up I needing a full re-core when (If i hadn't tinkered) a simple, cheaper repair might have been possible.

So within the week I was appropriately poorer, but had a lovely re-cored radiator. As such - and despite having an alternative radiator from Peter, I plan to refit that same old radiator again! As it's been re-cored at least twice to my knowledge, I can't really call it my 'original radiator, but at least it has the right sized screw threads.