How can I find a radiator leak?

[eleanor_350]

My Griffin aluminum radiator has developed a small leak and I can't seem to find where it's coming from.

Does anybody know a good way to find it? Is there a good sealant I can use to fix it without clogging up my cooling system?

I've checked my hoses and it's not them. After driving it there's a small amount of coolant on top of the lower tank and a couple of drops down on the frame. The only thing I can figure is one of the tubes has cracked or it's leaking where the tube joins the tank.

 

[pabear89]

You have an Expansion leak.
Clean rad and let engine warm to oper temp while watch the rad for leaks.
None found?
Let it get good and warm and watch after shutting down the engine.
The crack may be small and releases under pressure.

Take it out and Pressure test it.

 

[GypsyR]

Clean it up and let it dry thoroughly. Run to the store and get some Cruex spray. Other "foot powder" stuff might work if the main ingredient is "talc". I know for a fact Cruex works very well though.
Spray the stuff liberally anywhere and everywhere you even slightly suspect a leak. Gob it on for a nice coating.
Run the car up to tempurature. If you used Cruex you can even run down the freeway. Whatever it takes to cause the leak.
Stop and check it out. The anti-freeze mixture should have left a very visible trail right from the leak's source.
This works very well for locating oil and ATF leaks too.
When done, just rinse the stuff off with water.

 

[mustangdave]

Are you using an overflow tank? If not, radiators are designed to push coolant out when it get's hot; there should be a rubber tube that attaches to the rad. right under the cap tp guide the coolant down to the ground.
If you do have an overflow tank, there is a dye that you can put in the rad., run it, and the look for the leak.

 

[eleanor_350]

Thanks for the responses.

I'll bet it is an expansion leak since it hasn't leaked a drop in the two weeks it has been sitting in the garage. I'll warm it up and see if I can spot the leak. I'll get some Cruex if I still can't find it. I've fitted the car with an overflow tank, so I'm pretty sure it has to be a crack in the radiator somewhere. Where ever it is, I hope I can fix it. It would be a pricey radiator to replace.

Thanks again for everybody's input.

 

[86bluecobra]

you know there is a tool to pressurize your cooling system dont you. that way you can bring the system up to 15 psi or so and crawl all over engine looking for the leak without the chance of anything burning you. some time the small pinhole leaks will only leack when the system is pressurized so if the car has just been sitting it may not leak

 

[Agent Orange]

1) Rent a pressure tester from auto palace
2) clean area
3) Pressurize to 13-14 psi
4) done.