to check the heat exchanger, remove the end caps and check the interior
baffle to see there is no crud in there.
Get a battery
brush and use it to clean the inside and outside of the tubing joints to bare metal. Any crud in the joint will cause leaks
, so take your time cleaning
You will have to buy replacement rubber rings, and sorry, I have tried various o rings and washers, but only the rubber rings from volvo
do the job.
Once the cooling
system is reassembled, we even added caulking over the joint directly above the starter solenoid before adding coolant
to assure water
I usually fill the coolant from the highest point in the system to avoid any air, even pulling the thermostat to fill.
Once you are done , run the moter until the thermostat opens to make sure no leaks, and no air.