Coolant overflowing from expansion tank

[inlinesix]

Just now, Kklim said:

Petrol. Sylphy G11 1.5L auto. Only go over 3K rpm on NSH

That’s strange.

I only experience this in Diesel engine.

[mersaylee]

41 minutes ago, Kklim said:

Workshop diagnosed as blown head gasket. There was some oily deposit in expansion tank. 10 years liao (just renewed COE).

what’s the mileage on the car? 

Check engine oil cooler if your car has one. 

[Ichibawa]

Were you one of them who got caught in the congestion in JB before the Movement Restriction Order come into force?

[Kklim]

1 hour ago, Ichibawa said:

Were you one of them who got caught in the congestion in JB before the Movement Restriction Order come into force?

Nope

[Kklim]

2 hours ago, mersaylee said:

what’s the mileage on the car? 

Check engine oil cooler if your car has one. 

150K 

[Mkl22]

2 hours ago, Kklim said:

Workshop diagnosed as blown head gasket. There was some oily deposit in expansion tank. 10 years liao (just renewed COE).

Guess as much. 

[Ct3833]

3 hours ago, Kklim said:

Workshop diagnosed as blown head gasket. There was some oily deposit in expansion tank. 10 years liao (just renewed COE).

so just have to change the head gasket, should be cheap , good for you. what is the damage ? 

[Beregond]

13 minutes ago, Ct3833 said:

so just have to change the head gasket, should be cheap , good for you. what is the damage ? 

Change head gasket can be consider top overhaul liao. I doubt will be cheap. I guess 1.5k+- lol

[Kb27]

If head gasket blown, you should normally see white exhaust, then the overflow tank and radiator should be empty bcuz of the leak.

[inlinesix]

17 minutes ago, Kb27 said:

If head gasket blown, you should normally see white exhaust, then the overflow tank and radiator should be empty bcuz of the leak.

It is not a leak.  It is boiling water back flow into expansion tank.

It back flow to the extent that water level goes beyond maximum line and flow out of bleeding tube (expansion tank).

I only see this in diesel engine.

[mersaylee]

47 minutes ago, Kb27 said:

If head gasket blown, you should normally see white exhaust, then the overflow tank and radiator should be empty bcuz of the leak.

I’m not convinced it’s HG too

[Scholesy]

20 hours ago, Ct3833 said:

so just have to change the head gasket, should be cheap , good for you. what is the damage ? 

head gasket and top gasket is different. if he has oil in coolant tank, then it is high chance the more serious head gasket. 

[Ct3833]

4 hours ago, Scholesy said:

head gasket and top gasket is different. if he has oil in coolant tank, then it is high chance the more serious head gasket. 

Thanks for  sharing.

[Volvobrick]

4 hours ago, mersaylee said:

I’m not convinced it’s HG too

If HG blown it could be the result of a overheated engine, rather than the cause of boiling water in the expansion tank. 

Overheating usually coolant thermostat, fan (or related electrical circuit like relay, fuse, wire etc) , stuck thermostat valve.

First need to check if fan turning normally or not. 

[Beregond]

Normally overheat cos either water not enough(leakage) or fan not working.

20%chances is radiator choke.

The chances of water pump not working is even lower. I say about 2%. B4 the water pump fail. Normally its already leaking so can be easily detect.

When your hg blow. Not only u need to do a top overhaul. U need fix the root of the problem also. Example replacing radiator bababa. So a simply 1.5k for top overhaul with other stuff can easily hit 3k.

And owner must take note replaceing hg mean the engine head need to be skim abit. Mean your engine compression will be out.

Even after repair. U 'might ' have funny issue. Like water level keep drop even no leakage etc etc etc

Make sure u discuss with your ws b4 proceeding