A quality ethylene glycol coolant, containing corrosion inhibitors should be used. A 50/50 mixture of water and coolant is recommended. Antifreeze concentration should be high enough to maintain freezing protection down to -34°F (-37°C).
ff-1 and 1300G Models
These models have a sealed cooling system with two radiators and separate thermal expansion tank.
On 1300G models, it is not necessary to remove the cap to check the coolant level, because the expansion tank is translucent plastic. The coolant should be replenished if its level falls 3 / 8 in. (9.5mm) below the line molded in the side of the tank.
On ff-1 models, the cap must be removed from the expansion tank in order to check the coolant level which should be flush with the top of the pipe inside of the tank.
If, on either model, the level in the expansion tank is lower than it should be, check the coolant level in the main radiator, as well.
On both models, fill the main radiator to the bottom of the filler port. On the ff-1 models, fill the expansion tank so that the water just covers the pipe inside it. On 1300G models, fill the expansion tank up to the mark on its side. Add a good brand of an anti-corrosive ethylene glycol coolant, and water, in a 50/50 mixture.
Except ff-1 and 1300G Models
These models use a conventional crossflow radiator. Check the coolant level with the engine cold. To check the coolant level:
- Depress the black button on the top of the radiator cap to allow the pressure to escape from the cooling system.
- The coolant level should not fall more than 1 / 2 in. (12.7mm) below the plate welded inside the tank. Add a good brand of an anti-corrosive, ethylene glycol coolant and water (preferably distilled) in a 50/50 mixture.
- Install the radiator cap.
DRAINING, FLUSHING AND CLEANING THE SYSTEM
- Remove the radiator and recovery tank caps. Run the engine till the upper radiator hose gets hot. This means that the thermostat is open and the coolant is flowing through the system.
- Turn the engine OFF and place a large container under the radiator. Open the drain valve at the bottom of the radiator. Open the block drain plugs (If equipped) to speed up the draining process.
- Close the drain valves and the block drain plugs and add water until the system is nearly full.
- Add a can of quality radiator flush to the radiator, following any special instructions on the can.
- Turn the engine ON and idle the engine as long as is specified on the can of flush, or until the upper radiator hose is hot.
- Turn the vehicle OFF and drain the system again. There should be quite a bit of scale and rust in the drained water.
- Repeat the draining and filling process several times, until the liquid is nearly colorless.
- After the last draining, fill the system with a 50/50 mixture of ethylene glycol and water.
- Run the engine until the system is hot and add coolant, if necessary. Install the caps and check for leaks.