redid some of the plumbing on this jbl to change the upper coolant tubes and clean it up a bit and would like to pass on some info for other jbl owners, probably doesn't apply to other makes.
prior to the change the upper radiator hose exited into two 90 degree elbows, the coolant filler with cap, and then straight into the top radiator inlet.
the change involved going straight out the thermostat housing to the coolant filler with cap and then the two 90 degree elbows under the body work, out of sight and into the upper radiator inlet.
doing this has caused coolant to exit the filler fitting, even with a 21-25# rated cap. the coolant system was pressure tested and the cap was also tested and tested at 23#'s.
the bleed off is only when the thermostat opens which i assume increases flow of coolant through the tube, the thermostat has three 3/16" holes btw for bypass. my assumption is that the coolant exits the engine at such a force or with enough pressure to exceed the 23# capacity of the cap, previously with the elbows prior to the cap the the coolant was slowed enough, and after with the elbows after the cap there was enough force to exceed cap capacity.
no change was made other than moving the elbows. i am going to move them back and find out the result, hopefully the result will be acceptable
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