so i been having this over heating problem for a while and i finally got a new radiator, now it doesn't overheat at all but the coolant doesn't return from the bottle... no obvious leaks...(add coolant light comes on every few days) so now what?

 

Try to replace the Rad cap,and check your Hose from the Rad to the Overflow bottle.You may be losing it there.If not you may be eating coolant,but just a Small amount and that would be a bad Coolant seal..Oh also noticed the rad is NEW.so check out www.rotaryresurrection.com and hit TECH..it should have some instructions as to Properly fill and expel Air from the system.

 

so what you are saying is that if its eating it up in the bottle it could be a potential coolant seal? hmm i might have the same issue....

 

mine just flows out and doesn't return..

 

so it expands and doesn't contract

 

Make sure the coolant bottle isn't rigged wrong. Examine the cap very carefully and make sure that the hose from the radiator goes to the barb that leads to the hose that runs to the bottom of the coolant bottle. Look *very carefully*, it's actually very easy to screw this up.

 

oh..another thing is to Inspect the hose on the Rad .The Hose that goes from the Rad to the Overflow bottle.If that hose is Broke,or the Hose INSIDE the bottle is broke or Obstructed.it won't allow coolant to get Returned to the Rad.So every time the Engine Heats up.it expels coolant into the Overflew bottle,but can't get it to return...You should really,at first,see if you have Air in the Cooling system.If you have Done a Proper Fill up of the cooling System,then It Should NOT be "eating Coolant" from the bottle all the Time..It should just Expel the coolant Into the bottle when the thermostat opens,and the coolant expands, then Retrieve the coolant as the Engine cools down and the Coolant goes back to Normal temperature...Now,If the Air is Out and You have inspected the Hoses,clamps,etc on the Engine,and it is visually Ok(NO leaks,puddles,signs of Coolant),then you May have a bad seal,Internally..And the only way that you will Know that is IF the Car is Eating Coolant,Overheating,OR if you get the cooling system pressure tested...I hope that helps you out!

 

+1

Rad cap (negative pressure valve may be the problem), or maybe even air getting into the small hose or nipples to it.