I found a couple of leaks from the radiator yesterday, in both of the top corners, "front of the vehicle" side of the radiator. One is a weep, and the other is a pinhole squirt from a tube when the engine is at running temp.

I'm thinking of soldering them up without removing the radiator.

I can see the hole for the squirting leak, and am going to try to solder it up with a high wattage soldering iron, but the weeping leak is back in the fins somewhere and I'm probably going to remove the fins and carpet bomb the area with a small gas torch and solder stick.

My questions are, are there any known problems with soldering up rad leaks, and are there any problems that I could cause by doing this?

I'm guessing the main cause of the leaks is the age of the radiator, but contributory causes are recent 40+c ambient temperatures, and what I think is an incorrectly wired auxilliary fan. I had my hand down there today and found that the electric fan is blowing forwards - away from the rad and into the direction of the vehicle's travel.

That can't be right - surely??

Cheers
Rob

I've had my upper tank soldered a number of times, and each time it was a diminishing return -- arguing with the shop because they didn't want to do it, arguing with the shop when they claimed my coolant was all brown and rusty and I'd been neglecting my cooling system (when I had changed the coolant not 2 weeks before), etc. The last attempt at soldering the tank seam lasted about 1.5 years, but the upper tank seam had been leaking for the last few months with a crack in the solder that was visibly lengthening. I decided to install a new CSF radiator last weekend. So far it seems to be working well.

So... all that to say that in my experience radiator tanks (at least) can be soldered, but it isn't necessarily a permanent repair.

I've no personal experience with electric fans in a Montero, but common sense would seem to say the polarity for your fan motor is reversed <img src="/forums/images/graemlins/cyclops.gif" alt="" />

Eric W.

Soldering a radiator is possible and will work, but it is generally not permanent. Simple matter of different metals, after all you are soldering, not welding. But I've done it on HMMVWS and it held for a long time, good preperation will help with the longevity of a repair. Also check the mounting of it, that it is properly mounted and not getting a lot of flex. That is what causes the brealing, where it bends and cracks the seams. Good luck dude. <img src="/forums/images/graemlins/cheers.gif" alt="" />

My last radiator they silver soldered. You can not do that installed, however, it has to be drained and cleaned. But it's lasted for years.

Edward

You can't solder it with water in it - never get it hot enough. You have to remove the paint, sand the metal to shiny, use flux, and don't get it too hot (I like a propane torch over an iron). You'd be a lot better off if you could find a radiator shop to do the soldering. Not too hard to remove the radiator. And if it has two leaks now, it will have some more soon...

Turns out there were 6 leaks.

Both corners where the tubes join the top tank, front and back - but thankfully not middle, a 3mm split in a pipe and the outlet joint with the bottom tank had a long semi-circular crack in it.

Showed lots of older repairs inc the outlet split. Soldered it up with electrical solder and a small gas torch - 6 hours start to finish, mostly sanding. The solder seems to have done a good job. All back together and filled up, will look for signs of leaks and have a run out in the morning.

2.30am. Beer. Sleep.

Did you change the fan polarity while you were in there?

Eric W.

Well, I took her out for a few days, but hours of

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broke open the large crack on the return pipe again.



The smaller soldering held well.



I ended up getting a new radiator locally. It was a little larger than the original one, and had extra fittings, but fitted right into the space and only needed some new mounting holes drilling. I lifted it 1cm to get clearance over the chassis rail, and all but one section (yet to be padded) of the steering pipework is well cleared - no modification needed. This rad has exactly 1 liter higher capacity than the old one - so I'm hoping it'll do the job ok. I split the shroud and mount it in 2 pieces, but again - no further mods needed. It went on very easily and clears the fan all round, but is a little smaller than the surface of the new radiator.

New rad on the right


extra fittings


new holes


clearances






I have no idea what this radiator came from other than it's out of a Mitsubishi, don't know which model, but the temp guage now barely moves from rest, even sitting in traffic in 40' shade temperatures.

Sorted.

It looks like the "new" radiator is out of a gen 2 auto. The extra fittings are for the auto tranny cooling lines. They'll be fine you shouldn't need the crazy hose clamps on them. The tubes are isolated from the coolant.