But the surge bottle is always full. I overfilled the bottle prior to making my trip home. Got home to find coolant all over the undercarriage. Bottle was now at normal level. Take the truck to town one day, found a lake of coolant under the truck, in the area where I suspected a water pump failure. Bottle still fill. Had to pickup a Mini Excavator. Coming home temperature climber to 210* once...which is the highest it's been. Noticed fresh coolant on the front of the trailer. Bottle still fill. Returned the excavator, temperature never climber over 189. Got to rental center, fresh coolant on the front of the trailer. Got home, bottle still fill. Let the truck sit for 8 hours, gave the upper hose a squeeze...was soft.
Ordered the adapter for my Stant pressure tester. Want to see if the pump is leaking or if it is a hose. Also want to check the cap. Will leave the tester on and fire the truck up to see if a head gasket is done. Also will be buying whatever I need to check for combustion gasses in the coolant, ifor I do find the coolant system getting pressurized. Really hope I didn't cook a head gasket...
Any thought, comments or suggestions would be appreciated.

 

Sounds like coolant pressures are getting to high, and the cap is venting. If you are no longer full, then you have a problem

 

1. It's not a surge bottle, it a reservoir. Stop over-filling it!!! If you over-fill the reservoir you're just making the antifreeze people richer, because your truck is going to puke it out until the level is right!!!

3. If it continues when the level is right change your thermostat, radiator cap and radiator hoses.

 

Not to nit pick but it is called a surge tank...

Never over filled it. Have never filled it beyond the ridge that is about half way up the tank. This was done when it was cold. Was well below the cold fill line.
Cap, t-stats and hoses are all new.

 

FWIW you can have your coolant tested at a shop. At least we can have it done the same place we get our oil samples done.