Overheating????

[09nytro]

Big job now or bigger one later and more $$$$ .....hmmmmmmm.

 

[Blue Dave]

How can it be a sealed system if there is an overflow hose in the coolant bottle? Also,the hole has been there for a nice while with no problems until recently.

Spring loaded cap, just like a car automotive system. PSI of the cap per the FSM is 14-18 psi.

Agreed though, a pinhole leak will prevent the pressure from building, which in turn DRAMATICALLY lowers the boiling point. When the low pressure coolant touches hot engine parts, it creates steam, which doesn't carry heat nearly as well as liquid. The other problem with a pinhole leak is that it allows air back into the system as it cools down.

Fix the pinhole!

Bingo! The problem is the sucking of air back into the system when the system cools down and the pressure drops. This is why there is a reservoir bottle. The bottle allows for thermal expansion of the coolant when hot but equally important it allows coolant (not air) to be drawn back in to the system when the pressure drops during cooling.

You said radiator but I am wondering if you meant to say heat exchanger. Is it one of the running board heat exchangers? If so, it is a fairly easy job. Simply drill out all of the rivits to remove it. Any good welder with experience welding aluminum can fix the hole easily. If you have a pneumatic rivit gun the re-installation is no big deal.

Air in the system will definately cause overheating! Fix the pinhole and blead all the air out after refilling. When you refill with 50/50 (the stronger the concentration the less effective it is at transferring heat) add a bottle of Water Wetter which will further increase the coolant heat transferring efficiency.