david 3816: Car Overheating

Last week, my van was overheating. I stopped at a petrol station workshop and asked the mechanic to take a look at my vehicle's cooling system. He inspected all hoses, fan belt, thermostat, radiator cap and he notice all of the radiator hoses has hardened. The hoses are in poor condition, coolant fluid could have leak out.

Radiator hoses will wear out eventually. Rather than driving your vehicle until the problems becomes apparent with a breakdown, you should replace them all every four years or when the condition deteriorated.
He found there was a large amount of rust in radiator, and he suggested a radiator flush to clear rust contamination and replaces contaminated fluid.

If you're car still new, you must send your vehicle to service only by the authorised workshops during the warranty period. The workshop personnel are well trained according to the car specification and provide the right tools and parts to service your new car.

While you required to pay more what you get are the parts mentioned in booklet will be guarantee in that period. If you send to other workshop to give your car a great sporty look then you may cause your new car warranty to be declared null and void. Any modification is best done after the warranty period

After the warranty period end then you can send to any Ah Kow workshop (independent workshop).

I am not saying the independent workshop no good as some mechanics may from a authorised workshop and decided to open his own workshop. There come a time when most of the newer car will not be able to repair by independent workshop as it become too sophisticated.

One thing for sure benefit of sending to a independent workshop is you're able to learn more about your car. You'll know what spare parts has been changed and able to see what going through the service or repair. Any questions you might have you can direct ask the mechanics.

There are some independent workshop will work in partnership with a petrol station . Both will benefit from each other. Like the workshop do not have to worry about stocked up expensive lubricants and petrol station need not worry about unable to sell their lubricant products.

In our country we use the word petrol for automotive fuel. Naturally it sound correct but in America the word use is gasoline for fuel. They called it gas for short and that's why it sound awkward when they called it gas station. The Malaysian people when in America will wonder why these station sell gas only and no petrol?

Petrol kiosk cum workshop

Petrol Station have come a long way from just dispensing vending soft drink cans to providing convenience stores, automatic teller machine (ATM), automobile workshops and some even with fast food restaurant on its premises.

No waiting room for this auto repair shop, Mom don't mind as long as they provide reading material

My experience learned from car overheating

Your car engine cooling system works to keep your engine from overheating and any parts could be the reason of car engine cooling failure.

Before you know there is something wrong with the radiator there are symptoms like

1- Water/coolant dripping to the floor from the car ( not the aircon water dripping).

2- Hear a boiling sound from the radiator.

3-The water level continues to go down despite topping up the radiator tank and reserve tank level everyday.

Your cooling system components include the radiator, radiator fan, radiator cap, water pump, thermostat and hoses.

Radiator function

A radiator is a type of heat exchanger. It is designed to transfer heat from the hot coolant that flows through it to the air blown through it by the cooling fan.

Radiator Fan Function

The radiator cooling fan has an important job in the engine compartment. It can push air through the radiator core. Therefore radiator fan able to cool down the hot coolant in radiator fin and cool radiator will flow back to the engine.

Radiator Cap Function

The radiator cap is a simple yet important part of cooling system that we normally overlook. It's a pressure relief valve that prevents a dangerous build up of internal high pressure rupture within the cooling system. The cap vents release some pressure by allowing a small amount of coolant to overflow the radiator into the coolant expansion tank. When the radiator cools back down, a vacuum is created in the cooling system that pulls open another spring loaded valve, sucking water back in from the bottom of the overflow tank to replace the water that was expelled.

Water Pump Function

The purpose of the water pump is a simple one, making it to push the coolant through the hot engine block, hoses and radiator to cool the engine down.

Thermostat function

The thermostat is a vital components of your car's cooling system. Its job function is to regulate the temperature and keep it at an ideal level by allowing the upper radiator hose transfers the hot coolant.
When you start the engine, it’s very cold and require warm up. So the thermostat will blocks the flow of coolant to the radiator. When the engine warms up, the thermostat can starts to let coolant flow through the system.

Possible reasons on what makes a car overheat

What is the possible reasons that can cause a car to run hot. It is easier to narrow down the likely suspect.

Possible reasons

1) water pump is not working proper- Puddles of coolant or water underneath your vehicle or high temperature readings may be signs that your water pump needs replacing.

2) Leak- It could be a tiny leak in the cooling system and you losing the coolant. You won’t see it dripping on the ground

3) Bad radiator cap - can cause leaking radiator and overheating cooling system. Seals on the radiator cap are damage. Replacing the radiator cap is easy and inexpensive, not worth of fixing, it is most likely temporary. Eventually you have to replace the radiator cap.

An enlarged radiator cap gasket can cause the cap does not vent properly. This can result in coolant loss. (picture below- left bad cap, right good cap).

Caution: You should never ever open the radiator cap when the car's hot. The radiator cooling system is pressurized and opening them while it's hot can cause hot coolant and steam to escape resulting in serious burns or scald.

You've Been Warned!

4) Bad thermostat -
A bad thermostat may cause the reading fluctuate wildly temperature gauge could indicate that the thermostat needs to be replaced.

5) Checking a car's radiator hoses will involves squeezing them to see. Radiator hose should be firm when squeezing but not harden,swell, soft or spongy.

All the radiator hoses changed with the matching hoses

7) Car cooling fan not turning - most likely a problem with the thermoswitch.

The cooling fans are controlled either with a thermostatic switch and they turn on when the temperature of the coolant goes above a set point ( radiator is hot) and turn back off when the temperature drops below that point (radiator is cold).

Others components in the cooling fan circuit can also be the reason for not working include the cooling fan fuse, relay, thermostat and the fan belt driven fans (a bad broken or slipping belts), or broken fan clutch. All can cause engine cooling problems.

If the above parts checked satisfactory but still cannot avoid the car from overheating then it will probarly the car radiator needs your special attention.

How will you know you need to send to Radiator workshop?

When you pull the radiator cap off and shine a torchlight inside, look inside the coolant should be transparent (plus depend on what color of the coolant you use) , and the fins should be visible and clean.

If there is dirty murky fluid and small deposit that build up over time, it can cause the fins to clog and perventing the water flow freely.

We must clean condenser and radiator fins every 20,000 miles or every 4 years but most will neglect this maintenance obligation.

When you go to a normal workshop is like you see a General Practitioner (GP) doctor. GP decide if you needed to be referred for specialist. In my case a Radiator specialist.

I still encounter van overheating, I now know for sure my radiator require some detail attention to be sure its clean inside.

So next day I go to checked with the Radiator workshop. I intend to do a radiator cleaning and repair leaking if any. A normal servicing radiator job is to cleaned it out, soldering the core and pressure tested it for RM150.

I notice the workshop specialising in radiator and car air conditioning repairs and service. My guess is radiator and air conditioning system works on the same principle. AC condenser is just like a radiator which has tubing or coils and fins.

Radiator draw heat away from the engine and replacing the environment with cooler water drawn from the radiator. Making the engine much cooler.
Same like radiator, air conditioning also drawing heat away from it. As a result is a car temperature will go down significantly, which makes the car feel cooler.

After he removed the radiator side covers, he showed me the radiator in bad condition. It's badly corroded and is not worth fixing. When the radiator is deteriorate with age , it is likely the radiator won't last long anyway.Even after cleaning and repair by applying the bonding to the cracks and holes.

He recommend me to use a 3 row core radiator as the vehicle I use has dual air conditioning therefore will generate a lot heat.
Using a 3 row radiator will last long as when one of the row failed the other two still works.

Cooling will be efficient with the three row radiator fin. The more fins the greater the cooling area due to the greater surface area.

When he show me the new 3 row radiator, I was surprise as why it look like rusty? It's new right? He replied I am not the first person who asked.

What is the color of copper? It is a reddish, orange color.
Ooh..I see!

Again I asked, "Why is the car engine radiator made from copper?".

The radiator is made of copper because copper transfers heat very well.Elementary, my dear Watson.

Some customer feels it's no nice looking , so the manufacturer has to spray painted the fin black but after sometime the paint detoraited and stick on the radiator causing it to overheat. Now it comes without any spray painting. Why do we need the radiator to spray painting , nobody going to look at it?

I asked him whether is alright to use coolant again? He advice me that old van is like a older people should not taking too much medicine as the body organ cannot work as well it use to be.
Old coolant gets acidic and corrosive, and will eat all sorts of internal parts, from your head gasket to the water pump impeller.

Although I've change a new radiator but other part also will be affected when you use collant.

For old car we don’t recommend using Coolant. Using just water instead will do.

While using coolant you need to remember , any deposits at all in the radiator are bad and are caused by one of more of the following:

1) Incorrect coolant Coolant concentration too high – the correct mixture is coolant 70% and water 30%.

2) Mixing incompatible coolants. You should use only the coolant recommended by car manufacturer.

Another problem solved! Another one will appear. While the radiator man doing a last minute check he warned me air leakage somewhere in the exhaust pipe system.

Oh Dear, another appointment require with the Exhaust specialist. Van/Car with never-ending annoying problems. Sigh..