Despite its small size, the Toyota Starlet produces a lot of engine heat, so it's important that the radiator is in top condition to keep the engine from overheating. Typically radiators last for 8 to 10 years before wearing out, although this can be significantly shortened by infrequent flushing and maintenance. And once the radiator starts to show signs of wear, it must be repaired or replaced as soon as possible to prevent damage to the engine. So if you notice the following in your radiator, make sure to get it fixed or replaced immediately.
Leaks are a major problem with Toyota Starlet radiators particularly in older models. Leaks usually occurs at the seals and the seams in between the radiator panels, as the epoxy that holds the seams together will start to get brittle and crack over time. Rust and damage from flying rocks and other debris can also cause a leak in the radiator. If you notice that the coolant reservoir is frequently running out of coolant or you see visible leaks on the radiator body, have the radiator checked, repaired or replaced as soon as possible.
Another common problem with radiators is the buildup of mineral deposits in the small narrow tubes in the radiator core. These deposits come from rust and the use of hard, untreated water as coolant, and will eventually cause the radiator tubes to become clogged and for the radiator to malfunction. Coolant flushing usually fixes this problem, although extremely clogged radiators may have to be replaced.
The radiator itself is vulnerable to overheating and is due to a number of causes. If the radiator appears hotter than normal, turn off the engine and allow it to cool down. Check the exterior of the radiator for any signs of leaks. If the radiator appears to be fine, check the hoses and seals; a greenish or bluish-colored fluid on the hose or seal indicates a leak in these components. You should also check the coolant reservoir to see if there is enough coolant circulating in the engine and refill it if necessary.