Thermostat Housing Split?
Discussion
Morning all,
long story short: thermostat unbonded itself, and let the water out. I was trundling round at 30mph, been going about a mile, and stopped as soon as the car beeped at me (but had been doing local trips that morning).
Didn't see any steam though, so assume the water was mostly cool. Because the car's temp sensor is in the thermostat, it triggered the warning as soon as the sensor was dry.
Here's a pic (note: can't seem to put it upright: the pipe running left to right is the main feed to the radiator)
the thermostat was about 4 months old (I had replaced as temp gauge was always reading low, though this is a common feature in Alfa Romeos 156's. It was a pattern part from ECP.
I've got a replacement from ECP (different brand) and I think before I fit it, I'll flush the radiator through with a hose.
I have a few questions for the PH collective though:
- any thoughts on why this might have split?
- a blockage somewhere building up pressure, with this the weakest link?
- just random component failure / poor quality control
- anything else?
I wasn't towing, going fast and it wasn't that hot, so can't think of a reason this would fail now.
Thanks,
Ian
long story short: thermostat unbonded itself, and let the water out. I was trundling round at 30mph, been going about a mile, and stopped as soon as the car beeped at me (but had been doing local trips that morning).
Didn't see any steam though, so assume the water was mostly cool. Because the car's temp sensor is in the thermostat, it triggered the warning as soon as the sensor was dry.
Here's a pic (note: can't seem to put it upright: the pipe running left to right is the main feed to the radiator)
the thermostat was about 4 months old (I had replaced as temp gauge was always reading low, though this is a common feature in Alfa Romeos 156's. It was a pattern part from ECP.
I've got a replacement from ECP (different brand) and I think before I fit it, I'll flush the radiator through with a hose.
I have a few questions for the PH collective though:
- any thoughts on why this might have split?
- a blockage somewhere building up pressure, with this the weakest link?
- just random component failure / poor quality control
- anything else?
I wasn't towing, going fast and it wasn't that hot, so can't think of a reason this would fail now.
Thanks,
Ian
thanks for the reply.
New one on this morning (quick, as connectors were hex drive).
All seemed well with a quick test drive - the temp gauge was up and down a bit more than usual around 80-90.
Alfa threads can't agree whether this bouncing is "normal" operation of the thermostat or not. Didn't do it with my previous two thermostats, but it makes sense (as the gauge is a direct feed from just inside the housing).
Guess I'll have a few days of driving with one eye on the temp gauge then.
Ian
New one on this morning (quick, as connectors were hex drive).
All seemed well with a quick test drive - the temp gauge was up and down a bit more than usual around 80-90.
Alfa threads can't agree whether this bouncing is "normal" operation of the thermostat or not. Didn't do it with my previous two thermostats, but it makes sense (as the gauge is a direct feed from just inside the housing).
Guess I'll have a few days of driving with one eye on the temp gauge then.
Ian
Ian Geary said:
thanks for the reply.
New one on this morning (quick, as connectors were hex drive).
All seemed well with a quick test drive - the temp gauge was up and down a bit more than usual around 80-90.
Alfa threads can't agree whether this bouncing is "normal" operation of the thermostat or not. Didn't do it with my previous two thermostats, but it makes sense (as the gauge is a direct feed from just inside the housing).
Guess I'll have a few days of driving with one eye on the temp gauge then.
Ian
might have some air in the system, would be worth squeezing the hoses a few times with the engine running, also keep an eye on the coolant level as if the air leak clears then your coolant will drop!New one on this morning (quick, as connectors were hex drive).
All seemed well with a quick test drive - the temp gauge was up and down a bit more than usual around 80-90.
Alfa threads can't agree whether this bouncing is "normal" operation of the thermostat or not. Didn't do it with my previous two thermostats, but it makes sense (as the gauge is a direct feed from just inside the housing).
Guess I'll have a few days of driving with one eye on the temp gauge then.
Ian
As for the failure, faulty part or a bit of over-zealous tightening of the hose clips may have weakened it.
Plastic isn't a great material for a thermostat housing, is the replacement also plastic?
Hi,
Coolant has been dropping in the last day or so, which I guess is the air coming up.
I go easy on hoseclips- I tend to use a screwdriver socket rather than wrench.
The replacement is indeed plastic, but the plastic didn't split or fracture, it was the entire plastic assembly coming unbonded from the metal housing.
Hey ho, all fixed for £22, could have been worse.
Ian
Coolant has been dropping in the last day or so, which I guess is the air coming up.
I go easy on hoseclips- I tend to use a screwdriver socket rather than wrench.
The replacement is indeed plastic, but the plastic didn't split or fracture, it was the entire plastic assembly coming unbonded from the metal housing.
Hey ho, all fixed for £22, could have been worse.
Ian
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