Radiator leak? Questions....

[MrShanks2U]

About 2 weeks ago I flushed my cooling system out and replaced the radiator cap. I replaced the cap because I noticed that whenever I removed it, there was never any built up pressure in the system. The new cap worked great for about a week. For about the last week, I've noticed that there hasn't been any pressure building up in the cooling system. The coolant was not disappearing...it was all present and accounted for. Well, this morning, I checked my radiator and overflow tank and noticed that the radiator was full but there was a noticeable loss of coolant in the overflow tank. I checked under the truck and there was no coolant on the ground. I then drove to work. When I got there, a few hours later I checked...still no leaking. Right before I left work, I went out to start my truck and let it idle for a minute while I went to clock out. When I came back outside, there was a noticeable leak. Coolant was just dripping like crazy. I stuck my head under the bumper and noticed there was coolant running down the side of the radiator on the passenger side. I checked the upper rad. hose and there didn't seem to be any leaks from it. So now I'm thinking there may be a hole in my radiator. Now here are my questions:

1. Why such an abrupt leak? Could it be that the hole was plugged with something and it just now broke loose?

2. What is the cost comparison on buying a new radiator versus having my current one fixed via welding?

3. Is a repaired radiator going to be sufficient or would I just be covering up a big problem down the road?

4. If I should replace the radiator, where and how much should I be looking at?

Sorry about the long post. Thanks for the input!

 

[fourwheelford]

Are you sure its not the overfill tube leaking, if it has a leak in it it will only leak sometimes because it is really high on the radiator. Look for any amount of water evidence, the upper hose might also be leaking from the underside where you cant really see it. Sometimes the clamps will eat into the hose when they get old and cause a leak I just replaced my lower hose because of that. On another note,

I have welded a radiator before and as far as I know its still going strong. Be aware that it is a form of welding but because the majority of radiators are brass it needs to be brazed and in capable hands a small hole can be brazed pretty easily. If your wondering about it take the radiator out and put it in a tub full of water,(plug the upper and lower hose holes) if there is a hole there will be bubbles kind of like finding a hole in an inner tube. Once the hole is pin pointed mark it and clean the surface with steel wool to prep it for brazing and find someone who can braze.

Something to be considered also is that your radiator is probably plastic like mine is, if thats the case you can test it the same way to rule out a hole but if there is one you are gonna need to get a new one. Im sure you could heat the plastic around the hole and mold the other plastic to cover the hole but thats a long shot. Maybe someone has a better idea than me.

 

[MrShanks2U]

I definitely don't think its the upper rad. hose. That was the first thing I checked. I ran my hand on the under side to check for leaking coolant but it was dry. I checked the overflow hose itself and didn't see any leaks there either. It's not leaking bad enough that I can't drive it to work. Though, work is only about 5 minutes away. I'm going to try and take the radiator out on Friday and I'll try the dunk test to find the hole. A friend of mine is bringing a pressure tester to work tomorrow so hopefully I can find out a little more from that tomorrow. I did find some radiators online. The going rate seems to be about $95 + shipping all the way up to about $150 shipped. At those kinds of prices, I may just get a new radiator because I can't see any shop charging less than $50 to braze/weld/whatever.