Hi all,

On my way back from deer hunting last night I noticed I have a small leak in my all aluminum radiator. (Didn't shoot any deer but I did have a spike bull elk walk past me at 25 yard with out knowing I was there!)

With the snow coming as I write this, I am likely looking at needing at least a temporary fix to plug the hole while the radiator is in place until I can get a stretch of good weather that will allow me the time to remove it and take it to the local welding shop for a proper fix. The Blazer is my only snow capable vehicle, hence my need for a quick fix now. With the temporary fix, I will likely stay only in town (of 25,000) so that I will not have to worry about being stranded away from civilization.

The leak appears to be more of a pin-hole type leak. I have not been able to even see it yet although I'm guessing it is on the main side reservoir (on the driver's side) and not the fins (I hope).

So, do you any of you know of any products such as JB weld that could be applied to plug a leak? Any first-hand experience with such fixes? Draining the cooling system to properly apply a temporary fix will be easy to do.

Thanks

 

Flex Tape

I'm actually serious. That stuff is amazing.

 

You don't have to convince me Flextape is great. Unfortunately, I don't think it will work for my situation as there is nothing around which to wrap it.

 

If you can get access to and prep the leaky area properly, I'd say give JB Weld or an epoxy that can handle heat a try. With winter coming (late arrival thus far here at the house) I'd give whatever you use a bit more of a cure time. I've used JB weld a number of times in the past with good results, unless I failed to prep the area properly. I've also used epoxies with good results, though never where there was any heat. Just make sure to use a stainless steel wire brush to prep the area.

Keep in mind that a weld shop may not want to work on the radiator at a later date due to having to remove whatever you use would have to be removed. I would imagine that if you do your temporary repair work properly, removing it would cause a thinning of the material that needed the repair. If it does work, leave it there. Could go years and years with no leaking. At worse would be throwing a new radiator in your ride.

 

Do you have any idea what caused it to crack and leak? I'm just curious, since I have the same radiator, and I'd like to avoid having the same problem.

 

First thing I'd do is determine what I was dealing with. Is it a crack or a pin hole? Where's the location? If you can determine exactly what you're dealing with you may be able to just set up an appointment with someone who does tig welding and get it fixed on the spot. If it's just losing a little coolant at a time just carry some with you till you can get it in to have it fixed. I sure wouldn't be taking it out in the toolies with a known problem. Radiators tend to go from bad to worse at the drop of a hat. Something else, if you do have it welded the welder should clean it up with a SS wire brush by brushing it until the metal is taken down to totally virgin aluminum, then the brushed area should get an acetone wipe prior to welding. It can be done with TIG welding but the TIG would be better. It will keep the heat more centralized to the immediate area. There might even be a local college that could do it for you. Good luck.

 

This is great advice. My own searches were taking me to thinking that JB Weld could be the way to go. The advice about the SS brush is good to know. I saw this provided before and repeated by eshaw below.

 

Tom,

I'll be sure to report what I find. I haven't had a chance to get out there and find the leak. The general location appears to be near where the cooling tubes meet the drivers side side-tank near the top of the side-tank.

 

Thanks for the ideas. I agree with you assessment 100%. I will be keeping it in town for now. It is a small town of 25,000 so I would never be far from home. What sucks is that I wanted to get out for one last weekend of deer hunting but I would not do that with a questionable radiator.

I had the radiator modified to add an oil cooler by a local shop less than a mile away so if I have to, I'll likely have them do the repair. I don't think the repair is the issue but it is hard to tell.

 

Well I had a dry (but cold) window today to check the radiator. I was not able to do a pressure test but that will be next. Below are pictures that show where the leak appears to be originating. It looks like it could be from where the horizontal flat cooling tubes enter the top of the drivers side side-tank of the radiator. In some of the pictures you can see the welds for where the internal oil cooler were installed that seem to be looking good. The only evidence for the leak to my eyes is the staining of the aluminum where the flat cooling tube enters the side of the side-tank.

Assuming my assessment is correct, I'm now thinking that JB Weld (or similar) is the way to go as I think I could get into the space with a small stainless steel brush and then force in the epoxy to seal where the tubes enter the side-tank.

Any other suggestions for the repair and/or the origin of the leak are welcome.

I will be trying to find the time to swap the cars in my one-car garage so I can do a proper pressure test to confirm the origin of the leak.

Looking down from top and a bit behind.

Looking from behind toward the left (outside). The radiator hose is just out of the picture in the upper left and the welds for the internal oil cooler are on the lower left.

You can see the coolant between some of the cooling fins. There is slight staining of the aluminum where the flat tubes enter the side-tank for the top 6 of them.

Closer view of the top several of the tubes.

Looking at the staining, especially around where the 3rd and 4th of the flat tubes enter the side-tank.



There is some rubbing on the surface of the side-tank between the 5th ad 7th flat tube that is due to the cut-down fan shroud. There doesn't seem to be any damage there but I'll be trimming the fan shroud there to prevent any more wear.