Obviously a blocked radiator is a source of flow restriction that needs to be checked. Determine static pressure drop of the air across the radiator core at varying air mass flow rates.
This can be done by simply squeezing the upper radiator hose to check for pressure in the system.
How to flow test a radiator. Drain the coolant from the radiator cool engine then disconnect the bottom radiator hose from the radiator. Smear some grease on the rubber of the stopper to assist in sealing the testers attachment. Otherwise you are dealing with an obstructed radiator core failed water pump or thermostat.
The water-flow rate is rarely the problem because the manufacturers water pump is designed to give the correct flow rate for ideal flow through the radiator for best efficiency. Remove the radiator cap and pour water into the radiatorwater should come out the bottom at the same rate you pour it into the top. When the work is complete Ike demonstrates to Lynn that the radiator has a good flow rate by plugging the lower outlet hole filling the radiator to the top then removing the plug and observing the strength of the flow.
The flow rate should include the thermostat. Recorded on August 17 2011 using a Flip Video camera. Take the cap adapter and screw it onto the pressure testers end.
Let your radiator cool before opening it to avoid serious burns and boil overs. To begin pop open the hood and find the radiator. If none comes out the radiator is completely blocked.
It is usually located right in front of the vehicles engine. To attach the stopper to the neck I used two very small C clamps one on each side of the neck. Air Should Flow from Front-to-Back and Bottom-to-Top When mounting case fans air flows across the open side towards the side with the protective grille like so.
Ike is the technician at Pankeys who does the work. Grasp the upper hose and push you thumb into the hose to check the resistance. The correct water flow throughout your radiators can be the difference between being warm or wearing an extra jumper around the house.
So the open side of the fan should face outside the case for intake fans on the front or the bottom and it should face inside the case for fans on the rear or top. Using clean and suitable water flowing through a 34 inch hose at 80 psi nominal 14-16. A professional may test a suspect radiator cap using a cooling system pressure tester.
Shine a flashlight in the radiator and see if any fluid is flowing. On models with a radiator cap remove the cap start the engine and let it warm up. Grab the top radiator hose and squeeze it when its under zero pressure to get a feel of what thats like.
Use a cooling system pressure tester. When the engine reaches operating temperature through the opening youll see the coolant beginning to flow. The tool is attached to the cap using a special adapter then pumped up to the caps pressure rating.
If the fluid is not moving or if the fluid resembles brown soup this is an indication that your radiator is blocked. Replace the radiator cap rev the engine to about 3000 RPM this does not have to be exact you just want to spool up the engine a bit here then squeeze the radiator hose again. Determine the heat rejection rate associated with a test radiator as a function of both the mass flow rate of air through the core and the mass flow rate of cooling water.
And when you are doing that make sure that you are squeezing on the radiators hose. Sludge air pressure o. If your radiator sounds like it is boiling this also indicates a blockage.
Check that the coolant can circulate. Before removing the radiator cap its best to see if the system is already pressurized. A fast way of checking the radiators flow is to ask someone to rev while you are checking under the hood.
Turn the car off and listen. Measure whether there is a flow differential DeltaT of at least 20C at the boiler. Cooler Flow testing must be performed at the transmission return line AFTER the coolerradiator Test MUST be performed at the transmission end to ensure that cooler lines are also clear Remove one end of cooler hose place in a measuring container Start engine idle for approx 15 seconds.
Therefore if there is a clog or a fault in the hose it will stiffen making it quite challenging to press on the tube. Remove the radiator cap on a cold car and start it up. Turn off the boiler for at least two hours for the system to cool off.
Turn on the boiler from cold. The red dots mark the positions of the two clamps. Now remove the radiator cap by pushing it down first and then twisting it counter-clockwise.
Put a bucket under the radiator remove the bottom hose which should allow both the radiator and the block to drain.