Some of you may remember that about a year ago you gave me some advice
about repairing a leak in my Fordson Super Major tractor radiator. It's
a long story, but I only just got round to having a go.
The filler cap isn't on top of the radiator. It's on the end of a
horizontal pipe about six inches long which protrudes from the back of
the radiator. Where the horizontal pipe is joined to the radiator there
was a leak on the underside. It had been badly repaired by dumping lots
of soft solder on the joint in the past.
I drained the radiator, took it out and laid it flat on the workbench. I
put some wet rags around the top of the tubes to protect them from the
heat. I used a medium sized burner on my Sievert propane torch, and
began to gently heat the joint. I applied some Fry's "Powerflo" flux
with a brush. The solder started to melt, and I flicked it off with the
All very well and good, but there was a lot of solder there. I kept
flicking it off. The gap got larger. After a minute or so it looked like
I'd cleaned it all out, so I started wiggling the pipe. I wanted to
disassemble the joint, as it was filthy. It wouldn't come out. More
heat, more wiggling. At this point disaster struck. I hadn't realised
that the pipe was in fact made from two pieces of pressed brass sheet
soldered together. The melting point of this solder must have been the
same, as it popped open along the side seams.
I switched off the torch and starting thinking about what to do next. At
this point I noticed that the pool of excess solder on the bench had
turned into the shape of Pac-Man, who appeared to be laughing at me. You
can see the solder Pac-Man here:
Pac-Man, you cheeky blob, I am going get revenge for this!
I looked at the joint for the few minutes. I noticed something which I
had not seen earlier. There were two rivets under the grime on the top
surface of the radiator holding the joint together, which was why it
wouldn't come apart. I should have seen those earlier. I should probably
also have figured out, from having visited a car radiator factory in the
past, that these things are soldered in ovens when they are ultra clean,
not with a propane torch in a shed.
I gave the joint a good clean with a wire brush, held it all together
with some G-cramps, and had a go at soldering it back together. It
wouldn't work. The gap was too large (well over 1/16") and most of the
solder fell inside the radiator. That which didn't was only wetting the
metal in patches, despite an abundance of flux. Perhaps the gap was
bigger than it should have been. Maybe this explained the cracked solder
and the leak, or maybe it happened while I was wiggling the pipe.
At this point I gave up. I guess I could have drilled out the rivets and
taken the joint apart to clean it, but it was filthy and looked like an
impossible job to get it back together.
I wish I had seen the rivets beforehand. I guess the moral is that you
need to clean and inspect a job really throughly, and avoid making
assumptions. As one of my schoolteachers used to say, assume makes an
ASS out of U and ME. Even if you don't often screw up, it's still
annoying when you do. Perhaps even more annoying. We live and learn, I
On the plus side, I didn't ruin a good radiator. It was a fairly crappy
radiator anyway. And it was interesting to see that the wet rags kept
the tube and manifold joints cool enough to keep them from melting
(perhaps they are also made with a higher melting point solder). To be
honest, I'm not sure I would have been able to fix the joint even if I'd
seen the rivets first. There was such a heavy layer of grease and oxides
on the metal.
So it looks like I'm going to have to buy a new radiator. Damn. Or I
could look for a second hand one, but I'm not sure second hand radiators
are worth the effort. Any thoughts?
Radiators are clearly not easy to fix :-(.