Auto, Car, Truck Radiators

What a Radiator Does

Radiator Maintenance

Adding Coolant

Although it is important to keep coolant in this tank, if you have a coolant leak and add coolant only to the tank, you may not get any coolant into the radiator. YOUR CAR MAY STILL OVERHEAT!!!

CAUTION!!! DO NOT OPEN A RADIATOR CAP WHEN THE CAR IS HOT OR OVERHEATED!!!

If your car overheats, go get a drink somewhere, or listen to the radio fo a half hour or so. Give the radiator some time to cool off. If you don't have water, walk and get some.

Don't bother with the plastic coolant recvovery tank at this point: ON A COOL RADIATOR remove the pressure cap AT THE RADIATOR.

Fill the radiator with coolant. (or just water if you've got a leak: no point in polluting the ground water with antifreeze. If you suspect a leak, you might want to go with just water until you fix it. Leaving the radiator cap loose can slow down a cooling system leak. (Most caps click twice before fully tight: the first click releases the system pressure)

Only after you've filled the radiator to full capacity should you put any coolant in the plastic coolant recovery tank.

Since a slow leak can lose engine coolant without drawing new coolant from the plastic recovery tank, it's important to check your coolant level AT THE RADIATOR ITSELF from time to time (COOL ENGINE ONLY!!!)

If the radiator isn't completely full, the coolant recovery system (plastic tank) won't work at all.

How a Radiator Fails

Food for thought: Why not run distilled water in with that antifreeze instead of tapwater? Our water here is pretty hard, and a couple of gallons of distilled water only costs a couple of bucks....

Pre-Mixed Antifreeze

WATCH OUT!!!

If it says "Pre-mixed coolant" or something like that, this is antifreeze with the water already added. A good thing about this would be if you're doing a complete cooling system overhaul and don't want to go to the trouble of buying distilled water and then calculating the exact ratio of antifreeze to water.

JUST DON'T THINK YOU'RE GETTING FULL STRENGTH ANTIFREEZE!!!

You'll come out cheaper providing your own water.

A CUTE TEST FOR A CLOGGED RADIATOR

FIRST TEST

SECOND TEST

HOW TO FLUSH YOUR COOLING SYSTEM

The best flushes are two part: a strong acid and a neutralizer. The one part flushes aren't as strong. The strong flushes get rid of more scale and deposits, but you run the risk of 'eating through" the extremely thin and cheap radiators, freeze plugs, and heater cores they have today.

Prestone and others make a "backflush adapter" which fits in a heater hose and accepts a garden hose.

No matter how you do it, I'd replace both the top and bottom hoses, bypass and heater hoses, and possibly the thermostat.

When you remove the bottom hose almost all the coolant will drain out of the system. You really shouldn't just dump this coolant: be a little "green" and at least pour it down a drain so the wastewater treatment plant can deal with it before it gets in the groundwater!. The best is to go to your regular mechanic and let him put it in his coolant recycling tank. Mechanics are required by law to have one.

Fill the system with water. If you decide to use flush, add it at this time. Start the engine and let it warm up. It might be necessary to hold your hand over the radiator filler while squeezing the top hose: the thermostat will be closed and may keep the water from circulating. If no water touches the thermostat, it WILL NOT OPEN AND OVER HEAT YOUR VEHICLE!!! I always drill an 1/16 inch hole in the flange of a thermostat to keep it from "air locking" like that: the better thermostats already have a bypass hole for this purpose.

Once it is warm, follow the can directions regarding the flush, if you use it. If you aren't using flush, skip these next few steps.

If it's a 2 part flush, remove the bottom hose or open the radiator drain cock if it has one. (the drain cock will usually be on the opposite side from the bottom hose inlet on the radiator.) After it drains, replace the bottom hose and refill the system as outlined above. After it has been refilled, remove the top hose. Get a piece of pipe that fits either over or inside the top hose: this will make this step a lot neater.

Put a hose in the radiator filler and turn it on. Run the engine. Fresh water is being added by you via the radiator, the water in the engine is being pumped out of the top hose. Run water through it until the water exiting the top hose runs clear.

Re-attach the top hose and add the neutralizer, if a 2 part flush. Drain and repeat both of the above steps to remove the neutralizer from the system. If a one part flush, as soon as the water runs clear you are ready for coolant. Drain the system as outlined above.

Reattach all hoses, put in the antifreeze first. Complete the fill with water.