Overheating

Hi there,

Overheating during slow driving can be caused by the cooling fans not operating or are weak but you mentioned hard acceleration will cause the reading to shoot up, I think it could be due to air trapped in the cooling system.

You said coolant level is okay, is it the reserve tank? What about the radiator? Is it full when cold?

Hi,

When the engine overheats, the AC will stop operating.

Since you just changed the radiator, there is no need to flush it. Most probably the system was not bled to remove air pockets.

Since the radiator fluid is not visible, then you need to top it up and run the engine for a short while without the radiator cap to bleed the air out of the system. Keep topping up when the level drops until the the level stop dropping. If you keep the engine running more than five minutes, turn on the A/C to get the fans working so as not to allow the coolant to heat up to much which might splurge out.

Replace radiator cap and it should be okay.

After bleeding the system keep monitoring for a few days, fluid should be visible when cold. Top if necessary because there might still be minimal air trapped.

Now for the bad news part.

If overheating still occurs and fluid level drops in the radiator but not the reserve tank, then you might have a blown gasket.

Hi vitamin,

If no heated air, check the following

1. Clogged heater hoses.

2. Clogged heater valve.

3. Faulty air mix door.

4. Air mix control cable adjustment.

I believe you need to check the coolant level again when cold. You might have a leakage in the heater core.

It is critical that you do not let your engine overheat like that again. If it starts to overheat, turn the blower fan on hot and high to pull some of the heat away from the engine and shut off the vehicle.

As to why your engine is overheating, it could be numerous things. Faulty water pump, thermostat, low coolant, coolant leak, etc.

First check is to much sure you have coolant, if you are low on coolant you have a leak and must get the system pressure tested.

Good luck.

Well hopefully it is not a major issue.

Good luck with the vehicle.

Hi Mattymedals,

Thank you for the donation.

If you are loosing coolant and the reserve tank remains the same, it could mean the following :

1. Bad radiator cap.
2. Leaks in hose from radiator to reserve tank.
3. Excessive air in system.
4. Bad head gasket. This problem usually increases the coolant level in reserve tank.
5. Fast leaks in cooling system.

If it is a bad head gasket, repairs can be more than $1,000.00 depending on what needs to be done.

A pressure test would determine if the system is leaking.

To check if the head gasket is bad, here is a simple way.
Ensure there are no air in cooling system. Run engine with radiator cap open and top up if necessary. If coolant level does not drop, close radiator cap.
Remove hose from reserve tank.
Insert hose into a transparent botle filled with water.
Start and run engine.
Run till radiator fan comes on.
If there are bubbles in the bottle, run for a while longer until the air has been bled out of cooling system.
If bubbles continues and does not stop, the head gasket is bad.
Try sudden reving of the engine and note if the bubbles increases at that instance. If yes, gasket is bad and compression is leaking.

And use a transparent bottle filled with water.

That should not happen. Check if the hose to reserve tank is clogged or kinked. That would cause pressure to build up and blow the hose off.