Engine Heating?

Guy:Incognito

How quickly should an engine heat up? My 94 Rover 620i (accord engine) heats to normal driving temperature ( tiny bit below half) in 4 minutes (timed it just now). Does this seem a bit quick?

The reason this comes up is that, driving home last night, the temperature shot up when I turned the heater on (standard heater, not aircon etc). this happened about half a mile from home so I turn turned the heater off and it dropped. When I got home there was not water in the radiator or expansion bottle. I filled up the radiator and all seems normal this morning . But the car heating up in 4 minutes seems quick to me. I never took any notice before. My dad drives a 94 accord (same engine) and he reckons his doesnt heat up that quick.

Plus his radiator sprung a leak last week, although radweld seems to have sorted that. He thinks the water pump may be on the way though.

BrianD3

4 mins to warm up does not sound very abnormal. Some cars heat up quicker than others. Various factors affect this eg whether it's an alloy or iron engine block, coolant volume and composition, thermostat temperature etc. Also it would not be a surprise if a 94 Rover and a supposedly identical 94 Accord heated up at different rates as after 11 years neither cooling system will be operating as efficently as it did when new.

But it is suprising that the temperature gauge went up after you turned on the heater. Might be a concidence. You would think it should go down.

Temp gauge might be faulty. Also or it might be one of those fake gauges which don't register any change in temperature unless it's something dramatic.

Anyway I would keep a close eye on the cooling system and coolant level for the next while. You will want to investiagate what caused the expansion tank to empty. When was the last time you checked coolant levels.

69 mustang

It sounds like you were just low on water and when you opened your heater valve your rad / thermostat water levels dropped to fill your heater, as your heater may have been empty.

Your Dad may leave his heater switch not totally in the blue which would make it take longer to heat up.

BrianD3

69 mustang wrote:

It sounds like you were just low on water and when you opened your heater valve your rad / thermostat water levels dropped to fill your heater, as your heater may have been empty.

Your Dad may leave his heater switch not totally in the blue which would make it take longer to heat up.

This would only apply if it was a valve heater. The vast majority of cars made after c. 1975 have an air blending heater.

AMurphy

Or you could have a heater water valve with a leak, so when you activate it, it leaks past some shaft seal.
Fast heating is not unusual, overheating is.

Next time you get it home, leave it running, check for leaks underneath, then turn on the heater and recheck after a few minutes.
Most engines cool down when the heater is turned on, not overheat.... unless you had/have a leak.

However, as indicated above, some engines do not have a heater valve, just an air blender, so the heater core is always hot.

My 89 camry has a valve, the 97 van a blender.

a_ominous

If this is something you have recently noticed and hadn't occurred in the past, you should get it checked out. I had a problem earlier this year: water pump went. I thought there was a leak in the radiator and filled it up the 3-4 times I used the car (motorbike is main transport, but used the car on icy mornings).
End result: head gasket needed replacing. This meant the car in the local mechanic's garage for over a week. And it cost me about 750 yoyos to get done. New water pump was about 130 euro of that.

You could bring the car to a main stealer and get their opinion on the problem and get an estimate. Then see if it's worthwhile getting the car repaired. If it's just a gauge, that shouldn't cost much to replace.

But bottom line is: don't leave the problem untreated, it could cost you more in the very near future.