47-55.1 Coolant leak?

[Livemeyer]

Originally Posted by jwhotrod

The whole idea of a puke tank is to allow the coolant in the radiator when it heats and expands to flow into the puke tank. When the system cools the coolant then flows back into the radiator keeping air out of the radiator, which is an enemy to good cooling. Now when you fill the radiator full, and it heats it could very well put enough coolant into your puke tank to make it "leak" or overflow. Now do not panic, and put more coolant into the system. It is just finding its level, when it achieves a proper level it will stop puking onto your floor. your cap is doing its job, maintaining pressure and letting coolant out into the overflow tank. I hope this helps.
Jim Worrell

Jim, the concept is not lost on me, and I have not panicked (I only do that if the engine is overheating). Problem is, it keeps happening, and I haven't been adding any more coolant, and it's a pretty big overflow tank. The one time I took it for a spin sans tank I had coolant everywhere. For a half mile drive I shouldn't have had it puking at all. There should be enough space in the radiator (it's more than a half-inch below the top of the radiator) for the coolant to expand. The tank is there to catch the coolant when it does overheat and the coolant pukes. I wouldn't expect it to do this every time I drive the truck. I spent part of my day today making a new mount for the tank (it was previously on the fender and wasn't level) so tomorrow I plan to do the coolant system leak test.