Cast Iron Radiator Repair ?

Intplm.

Was wondering if anyone has had any success using boiler seal or similar product to repair cast iron radiators.
I have tried it out of desperation and sometimes it works, sometimes it doesn't. I know that it is meant to be used for boiler leaks.
In general I don't like to use any of this type of product for anything unless as A absolute last resort.

Does anyone have any repair suggestions . Anything thats been tried that has worked?

rlev11

Around 10 - 12 years ago I had a vertical crack around the vent hole, I took the area down to bare metal, slapped some JB Weld on it, and it has been fine ever since.

Intplm.

JB Weld? @rlev11 thanks.

I have a nice Cast Iron Rad that I do not want to change but am not to enthusiastic about using internal type boiler seal either.
If I do use the internal stuff that reacts inside a vessel (boiler, rad etc.) I know that I'm taking a chance on sealing holes that I need and possibly causing more headaches.
Plus, I'm not as strong as I used to be and am not looking forward to moving this heavy weight.
Not sure I want to try a used one either but.......?

JB Weld might try.

Anyone have any other ideas. Your thoughts are, and will be most appreciated.

Jamie Hall

I've had a couple of radiators with leaks between the sections. On some, I've repaired the "right", but two were in situations where that wasn't an option Take the area down to bare metal, as @rlev11 says, make sure there is no oil or grease etc. present, and put JB Weld on. So far (about 10 years), so good...

Intplm.

@Jamie Hall , @rlev11

Thanks for the advice. Looks like a JB Weld repair is in the future

ethicalpaul

I think I have to examine this possibility too. I have a nice old radiator from my living room that started leaking at the bottom between two sections in the middle and I wonder about taking it apart and removing the rotten section(s).

Even made smaller it would be way better than what I replaced it with, a modern radiator with these comically tiny sections that isn't cutting it.

Intplm.

@ethicalpaul
The problem that I'm having is that I cant find the leak ! That's why I was thinking about using a boiler seal type powder or liquid.
JB WELD sounds good but I'm not sure where to start with the repair.
That section removal thought . Hope you don't have to come to that. I tried it a very long time ago. Couldn't get the section to fit without leaking and over time had to scrap the radiator. It was in a utility room and wasn't a big deal getting rid of it.

Jamie Hall

@ethicalpaul -- taking a radiator apart takes a brave man. I've done it. Usually one finds that the can of worms just won't crawlf back into the can... I'd just try some JB Weld on the leaking joint first. You can always chisel the stuff off later.

If you do go to take it apart... I've had good luck laying the radiator on its side and using the kind of tool auto mechanics use to remove ball joints to very carefully spread the offending sections apart (use two -- top and bottom -- and go evenly on both). You may find -- as I have -- that the problem is that the nipple joining the two sections is rotted out. The ideal thing to do is to get a new nipple machined -- there is a company that does that, but I can't find the contact information. The less ideal solution is to turn the nipple so that the rotted side on top, and then reassemble the thing using red RTV to make a gasket all the way around the joint. That's worked for me... Use pipe clamps to pull the sections together -- don't use the tensioning bars. Just tighten them no more than half a turn beyond finger tight.

ethicalpaul

Thank you @Jamie Hall, this might be beyond even my level of can-worm-opening, but it's just sitting on my front porch now, so it's a no-harm-can-be-done scenario. It's not that pretty so I should go to an architectural salvage and get a nice one.

@Intplm. how do you know it's leaking?

Fred

@Intplm. , boiler seal is probably the worst idea. First off, it tends to clog things up, secondly, for it to even have a chance to work, it has to be able to physically get to the leak. It's the goop itself that blocks (or attempts to block) a leak. Pouring it into the boiler may get a little vapor to the radiator, maybe, if it can be carried with the steam and pouring it directly into the radiator is a really bad idea in that it will wash back through a wet return with condensate and if the wet return has any gunk in it, that will likely be the place where it will settle and block the return of condensate to the boiler. You don't want that. If the jbWeld doesn't work, find a replacement radiator of similar size (EDR).

Intplm.

@Fred . The way I have used it with some success (guessing the amount) is to put it directly into the radiator through the valve spud. Sometimes it works, other times not so much.
And I understand that it can do more damage. Boiler seal doesn't care what holes it plugs.

@ethicalpaul , Its leaking on a baking pan that has been placed under the radiator. Just can't seem to pin point the area of the leak.

ethicalpaul

Oh, well dry the pan and put newspaper on the pan and watch for the drips to hit?

Fred

You are going to have to disconnect that radiator and lay it on its side. You will likely see a rust spot at the pin hole, unless it is at a nipple between the sections. You will have to have good access to the leaking area to clean it for the JB Weld to hold. Trying to fix a hole in the bottom , in place is not likely to be too successful.