Odd coolant leak ideas?

[chillman88]

Hey all,I haven't dared drive Diego this week but what's bugging me is not being able to track down this leak.

Radiator froze up in mid December. Topped it off and put the correct mix in it, couldn't see any leaks, it was fine and held coolant.

Last Monday I got halfway to work and it overheated. Put 3ish gallons of tap water in and drove it home. Topped it off and it's held it's level for several days sitting with the block heater plugged in. I checked it Tuesday, Thursday, and now today (Saturday). Level is full.

Can't locate any leaks, even after I got home from work and topped it off. Overflow bottle was empty, and oil looks fine. Heater core was brand new same day I bought the truck and passenger floor is dry.

My thoughts:
1. Can't be pressurizing the cooling system, the overflow would be full, not empty.

2. Can't be an obvious leak or it wouldn't be holding it's level sitting.

3. Oil is fine, can't be an internal leak.

I'm left with very small/slow seeping or possibly a crack that only opens up when it gets very hot?

Anyone have a better idea? Haven't had a chance to pressurize the system yet.

I'm tempted to flush the system and put some stop leak tablets in.

 

[BrianX128]

Overflow hose leaking and never letting coolant back to overflow tank? I had one crack at the radiator cap on my straight 6. Coolant hit fan and would go everywhere. Was so confused until I saw the coolant by the cap.

 

[chillman88]

Overflow hose leaking and never letting coolant back to overflow tank? I had one crack at the radiator cap on my straight 6. Coolant hit fan and would go everywhere. Was so confused until I saw the coolant by the cap.

No coolant traces there but it's a cheap fix so I'll probably try it anyway.

 

[Thewespaul]

For your projects you really need one of these around. Makes coolant leak testing easy. https://www.amazon.com/Goplus-28-Pi...jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==