Car Repair filter. Leaking radiator help.

March 4, 2005 10:48 PM

Car Repair filter. Leaking radiator help needed.

My radiator has developed a hairline crack in the steel, just below the spout for the cap.
This is letting out steam when the car is hot (although the engine seems to be staying cool as long as there is water left).
See pics here:
http://www.bystander.net/temp/DSCF0002.jpg
http://www.bystander.net/temp/DSCF0003.jpg
Is this sort of thing repairable, or will it require a whole new radiator?
The car is a 12 year old Misubishi Verada, FWIW.
Bonus points if anyone can suggest a patch up that will let us drive 100 miles on Monday.

posted by bystander to Travel & Transportation (12 answers total)

I'm no car buff, but on Mythbusters, they used a raw egg in the radiator to stop the leak.

Not sure what the long term effects or benefits are, but supposedly it works.
posted by purephase at 11:44 PM on March 4, 2005

i'd get some copper-based stop-leak. honestly, i'm more concerned because it's at a serious flex point, and becaue its' so long. i'm not sure if stop-leak of any kind will be able to handle the pressure in that manner. maybe try stopleak and a high tempurature expoxy. that's about the best i can think of. if you're handy at all, replacing a radiator is a pretty simple task. it can be done in about an hour in your driveway or garage. all in all, i think you're going to need to replace it. i just wouldn't trust any kind of repair on a crack like that.
posted by quadrinary at 11:52 PM on March 4, 2005

Yeah, that definitely looks like a replace or professionally repair issue there. The egg trick apparently works. Another one that does work is to put a bit of black pepper in the radiator. Of course, neither of these is good for your cooling system, and should be looked at only as a stop-gap to keep you from blowing out all your coolant until you can get it fixed.

It'll probably get you 100 miles, though.
posted by jammer at 12:01 AM on March 5, 2005

Do you have a garage? I'm with quadrinary-- you want a high-temp epoxy. The problem is that it's winter for most of us and high-temp epoxy needs room temperature to cure properly. Go to local hardware stores and look at the specs. But if you can't get the radiator to the required temperature on the packaging, don't buy epoxy.

You also might try Krazy Glue. Which sounds absurd, but I know people who have done durable car repairs with it. This might be a bit too hot for it, but it won't hurt to try.
posted by Mayor Curley at 5:47 AM on March 5, 2005

Forget the glue; it won't hold. Epoxy softens when heated, and won't stick to surfaces that aren't clean. (Baked-on antifreeze means it isn't clean.)

Forget the leak-stop. It won't seal a crack which has the kind of stress on it that you describe. Leak stop will also degrade the performance of the radiator, and may clog water passages in the engine. You do not want that.

Are you sure the crack is in steel? If so, see if a welding shop can braze it up. That's a permanent fix. A radiator shop could also braze it, but would make more money selling you a radiator, so they might be unwilling. If the area were not stressed, I'd suggest soldering it, but the stress would probably cause solder to fail.

If you can't line up a braze job, get to a junkyard and buy a used radiator, and put that in. Take it somewhere to be pressure-tested before you put it in.
posted by Kirth Gerson at 6:31 AM on March 5, 2005

I know that lots of mechanics use JB WELD for quick repairs...it's pretty cheap, and worth a try.
posted by lobstah at 7:03 AM on March 5, 2005

I second the JB Weld - it's an epoxy, but my experience is that epoxies have no problem at all with the temperatures we're talking about here. I've never used it on a car radiator, but one application to my home (heating system) radiator has held all winter. Make sure to clean the area well before applying, and don't apply with your fingers.
posted by notsnot at 7:57 AM on March 5, 2005

Do this on a cold radiator:
1) Wire brush the area well.
2) Clean the area with Iso. Alcohol or Vodka.
3) Mix and apply JB Weld to the crack.
4) Toss in some Stop-Leak for good measure.
5) Enjoy your trip.
6) Start saving up for a new radiator.

I've used JB Weld to repair a cracked block effectively, (the patch lasted 20,000 miles until I sold the car) so I don't think the heat is going to be an issue.
posted by Floydd at 8:38 AM on March 5, 2005

I fourth the JB Weld -- great stuff!
posted by LordSludge at 10:57 AM on March 5, 2005

Response by poster: Just a follow up.
I couldn't find JB Weld (maybe in short supply here in Australia) but it put me on track for a similar product called Quick Steel, which is an epoxy based putty.
It says it can set underwater, but I found it needed to be applied to a bone dry surface to adhere well. Four minutes later it is rock hard.
A second try seems to have the leak sealed, and I tipped in some radiator leak sealer for good measure.
It will go to the shop later in the week.
Another win for Ask Metafilter!
The quick steel doesn't seem to have a website, but you can see it here if interested:
http://www.vintagetractorspares.co.uk/Accessories/Pages/new_page_1.htm
posted by bystander at 1:37 AM on March 6, 2005

No JB Weld in Australia ?!...sounds like a marketing opportunity to me ! Good luck with the trip, bystander.
posted by lobstah at 4:42 AM on March 6, 2005

If you are not over heating, you could try running a non-pressurized cooling system. If you have a lever radiator cap, leave the lever up. Otherwise you would have to find a way to make the cap not seal. Most radiator caps have a rubber ring for a seal. You can just cut the rubber seal (but this ruins the cap if you ever do get the radiator fixed) or find a way to make it not seat properly. Pressurization of the cooling system just gives you a higher boiling point for your coolant. If you are not pulling a heavy load up a mountain at high elevation, you would probably be OK. A radiator shop may be able to solder the neck while it is still on the car, but a lot of new cars have plastic parts that would melt during soldering.
posted by 445supermag at 7:57 AM on March 6, 2005