Toyota Celica 1986-1993 Repair Guide

Cooling System


The cooling system is a vital part of an engine's ability to operate efficiently and to last a long time. Periodically clean any debris such as leaves, paper, insects, etc., from the radiator fins. Pick the large pieces off by hand. The smaller pieces can be washed away with water pressure from a hose. Carefully straighten any bent radiator fins with a pair of needle nose pliers. Be careful, the fins are very soft. Don't wiggle the fins back and forth too much. Straighten them once and try not to move them again.

A 50/50 mix of coolant concentrate and water will usually provide protection to -35°F (-37°C). Freeze protection may be checked by using a cooling system hydrometer. Inexpensive hydrometers (floating ball types) may be obtained from a local department store (automotive section) or an auto supply store. Follow the directions packaged with the coolant hydrometer when checking protection.


When additional coolant is required to maintain the proper level, always add a 50/50 mixture of ethylene glycol antifreeze/coolant and water. Do NOT use an alcohol type.


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Fig. Fig. 1 Checking the engine coolant reservoir

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Fig. Fig. 2 Coolant drain plug locations2S-E engine

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Fig. Fig. 3 Coolant drain plug locations3S-fe and 3S-ge engines

It is best to check the coolant level in the radiator when the engine is cold. This is done by checking the expansion tank. If coolant is visible above the low mark on the tank, the level is satisfactory. Always be certain that the filler caps on both the radiator and the reservoir are tightly closed.

To avoid personal injury, always check the radiator coolant level after the engine has cooled down. Place a thick rag over the radiator cap and slowly turn the cap counterclockwise until it reaches the first detent. Allow all the pressure to escape. This will allow the pressure in the system to drop gradually, preventing an explosion of hot coolant. When the hissing noise stops, remove the cap the rest of the way.

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Fig. Fig. 4 Coolant drain plug locations4A-fe, 5S-fe and 3S-gte engines

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Fig. Fig. 5 Pressurizing the cooling system with a special tool to check for leaks

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Fig. Fig. 6 Clean the radiator fins of any debris, which impedes air flow

It's a good idea to check the coolant every time that you stop for fuel. If the coolant level is low, add equal amount of ethylene glycol-based antifreeze and clean water. On models without an expansion tank, add coolant through the radiator filler neck. Fill the expansion tank to the full level.

NEVER add cold coolant to a hot engine. Always let it cool down first.

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Fig. Fig. 7 Coolant protection quality can be checked with an inexpensive tester

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Fig. Fig. 8 Check the radiator cap seal and the condition of the gasket

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Fig. Fig. 9 Check the filler neck and sealing seat for cracks or deposits of rust and scale

Avoid using water that is known to have a high alkaline content or is very hard, except in emergency situations. Drain and flush the cooling system as soon as possible after using such water.

The radiator hoses and clamps and the radiator cap should be checked at the same time as the coolant level. Hoses which are brittle, cracked, or swollen should be replaced. Clamps should be checked for tightness (screwdriver tight only! Do NOT allow the clamp to cut into the hose or crush the fitting). The radiator cap gasket should be checked for any obvious tears, cracks or swelling, or any signs of incorrect seating in the radiator neck.

Most permanent antifreeze/coolant have a colored dye added which makes the solution an excellent leak detector. When servicing the cooling system, check for leakage at:

All hoses and hose connections.
Radiator seams, radiator core, and radiator draincock.
All engine block and cylinder head freeze (core) plugs, and drain plugs.
Edges of all cooling system gaskets (head gaskets, thermostat gasket).
Transmission fluid cooler.
Heating system components, water pump.
Check the engine oil dipstick for signs of coolant in the engine oil.
Check the coolant in the radiator for signs of oil in the coolant.

Investigate and correct any indication of coolant leakage. Also, while you are checking the coolant level, check the radiator cap for a worn or cracked gasket. If the cap doesn't seal properly, fluid will be lost and the engine can overheat. A worn cap should be replaced with a new one.


When draining the coolant, keep in mind that cats and dogs are attracted by the ethylene glycol antifreeze, and are quite likely to drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantity. Always drain the coolant into a sealable container. Coolant should be reused unless it is contaminated or has been used for several years.

Completely draining and refilling the cooling system every two years at least will remove accumulated rust, scale and other deposits.

Use a good quality antifreeze with water pump lubricants, rust inhibitors and other corrosion inhibitors along with acid neutralizers. Use an ethylene-glycol coolant, not an alcohol type. Make sure that antifreeze is not accidentally added to the washer reservoir.

  1. Drain the existing antifreeze and coolant. Open the radiator and engine drain petcocks. Set the heater temperature controls to the full hot position.
  3. Close the petcock and tighten the drain plug(s) to 9 ft. lbs. (13 Nm).
  5. Add a can of quality radiator flush. Be sure the flush is safe to use in engines having aluminum components.
  7. Idle the engine until the upper radiator hose gets hot. Race it 2 or 3 times and then shut it off. Let the engine cool down.
  9. Drain the system again.
  11. Repeat this process until the drained water is clear and free of scale.
  13. Close all petcocks and connect all the hoses.
  15. If equipped with a coolant recovery system, flush the reservoir with water and leave empty.
  17. Determine the capacity of your cooling system (see Capacities specifications). Add a 50/50 mix of quality antifreeze (ethylene glycol) and water to provide the desired protection. Add through the radiator filler neck until full and then fill the expansion tank to the Full line.