Bad water pump?

[Henkka]

I tried sesrching through the internet and forums for a solution before posting and didn’t find one so here we go. The temperature gauge on my w124 rarely shows the temp to be over 60c (140f) even when driving for long durations (4+ hours). When idle, the temperature rises to 80c. It seems like some of the coolant has boiled over multiple times because it seems to be rapidly reducing over time (no leaks). The hest blowers on the inside of the car don’t blow air hot enough for the interior to warm up fully, even on the ”max” setting. I’m thinking my water pump might not be working and that’s what causes all of these problems. Good to ask fellow mercedes drivers first before paying a professional to change it just to realise that wasn’t the problem.

 

[joderest]

hmmm, sounds like thermostat until you mention its using water.
have you checked for leaks anywhere ?, is oil ok.
Maybe you have both, a duff Thermostat and a coolant leak. You need to have it looked at

 

[Henkka]

hmmm, sounds like thermostat until you mention its using water.
have you checked for leaks anywhere ?, is oil ok.
Maybe you have both, a duff Thermostat and a coolant leak. You need to have it looked at

No leaks. Also worth to mention that the root of the exhaust (the part where it leaves the engine) is glowing red when driving normally, even here in Finland during winter time.

 

[LostKiwi]

If your waterpump isn't working your car will overheat.

 

[00slk]

If your waterpump isn't working your car will overheat.

And boil over losing water......

 

[Blobcat]

And boil over losing water......

Is that a good thing or not (in your case…)

 

[LostKiwi]

What you're describing sounds a lot like a blown head gasket.

 

[Henkka]

If your waterpump isn't working your car will overheat.

Isn’t that exactly what’s happening here with the water boiling over and exhaust glowing red?

 

[Henkka]

What you're describing sounds a lot like a blown head gasket.

But if the gasket was blown the thermostat would read the ”right” temperatures and tell me it’s too hot, not like in my case where it constantly shows under 60c,

 

[joderest]

so, the engine is showing as not warming up, but the exhaust manifold is glowing red hot, could it be because the engine is still showing as cold, the system is injecting an over rich mixture ( like on choke) hence exhaust getting hot ? ( i do not know if the car has that sort of system)

Guessing now, but i would still suspect a thermostat faulty.

 

[Henkka]

so, the engine is showing as not warming up, but the exhaust manifold is glowing red hot, could it be because the engine is still showing as cold, the system is injecting an over rich mixture ( like on choke) hence exhaust getting hot ? ( i do not know if the car has that sort of system)

Guessing now, but i would still suspect a thermostat faulty.

Can this be the reason for the boil overs too?

 

[mioba]

Get a stethoscope on the water pump. You need to be strategic here. Get a test done on the coolant gas to see of any blow by and if it has exhaust gas in.
Any engine thats overheated is not a good sign tbf.

Assuming your water pump died, this could lead to overheating and head damage (gasket, cracked head).

Just throwing some considerations out.

 

[LostKiwi]

But if the gasket was blown the thermostat would read the ”right” temperatures and tell me it’s too hot, not like in my case where it constantly shows under 60c,

If the water were below the level of the sensor it will read low.
Simple test.
Cold engine with coolant topped up
Squeeze top radiator hose and remember how it feels.
Start engine and run two minutes.
With engine running squeeze top radiator hose. If it's hard the head gasket is toast. If its about the same as previous it's probably ok.

The heater not working is down to air in the system. Classic symptom of head gasket failure along with loss of water.

No way a water pump failure will affect exhaust either.

Water pump failure of this type is also extremely rare - in fact I've never heard of it on a Mercedes.
In a Vauxhall/Saab/VW/Audi/Seat etc yes.
They have a habit if detaching the impeller or its blades from the shaft.

 

[joderest]

I have to say that your symptoms do not really fit simple solutions.
Thermostat stuck open would cause a slow heating up, not reaching running temperature and poor fuel consumption. I cannot think of any reason it would cause engine to boil over unless its failed so badly that its blocking the water system before the temperature sensor.
I think you would be better off taking the car to a decent indy and let them investigate the cause of your issues.

 

[Henkka]

If the water were below the level of the sensor it will read low.
Simple test.
Cold engine with coolant topped up
Squeeze top radiator hose and remember how it feels.
Start engine and run two minutes.
With engine running squeeze top radiator hose. If it's hard the head gasket is toast. If its about the same as previous it's probably ok.

The heater not working is down to air in the system. Classic symptom of head gasket failure along with loss of water.

No way a water pump failure will affect exhaust either.

Faulty water pump would mean that the coolant isn’t circulating as it’s supposed to therefore not cooling the engine down, right?
I’ll check the radiator hose the next time I’m on the move, thanks for the help.

 

[Henkka]

I have to say that your symptoms do not really fit simple solutions.
Thermostat stuck open would cause a slow heating up, not reaching running temperature and poor fuel consumption. I cannot think of any reason it would cause engine to boil over unless its failed so badly that its blocking the water system before the temperature sensor.
I think you would be better off taking the car to a decent indy and let them investigate the cause of your issues.

My 23CE is consuming about 10l/100km (23mpg) on highway.

 

[LostKiwi]

Faulty water pump would mean that the coolant isn’t circulating as it’s supposed to therefore not cooling the engine down, right?
I’ll check the radiator hose the next time I’m on the move, thanks for the help.

Yes but then the temperature gauge would show overheating.

 

[Henkka]

Yes but then the temperature gauge would show overheating.

Would it though? The hot coolant remains near the engine and the cold coolant is near the thermostat.

 

[mioba]

Yes but then the temperature gauge would show overheating.

To an extent, not if its measuring air since the rest of the coolant has disappeared.

 

[Henkka]

To an extent, not if its measuring air since the rest of the coolant has disappeared.

I tried adding more coolant and it didn’t help the problem.