1. Home
  2. Car Maintenance
  3. Strange overheating problem.

Strange overheating problem.

I went out in my van this morning, put the heater on, but no heat. Didnt think anything about it, then after 3 miles or so, noticed the temperature gauge was into the red. So, I pulled over, thinking the water level must be low - but no, the rad and expansion tank were normal. Left it 10 minutes, then drove another mile, where it went into the red again. Did a job for a hour, then drove toward home. Stopped off to order a water-pump for the van, as it was in the red again.Then drove back, when quickly, the temp gauge went down to normal, and the heater started pumping out heat.

Tried it again this afternoon, and all was well again. Now, I had this down as a failed water pump, but it seems it is working fine again.

Has anyone else had this happen? It was driven 10 miles or so, with no frost here last night.

Ta Alan.

Reply to
A.Lee
Loading thread data ...

temporarily stuck thermostat

Reply to
Mrcheerful

Sorry, didn't concentrate enough on the info: Actually the heater stopping points to an air lock, so unless you have recently filled the system then the likely fault is either a leak which the header tank didn't refill (seen on Japanese stuff usually) or a blown head gasket.

In the absence of leaks get a header tank gas test done to rule out the head gasket if possible.

Reply to
Mrcheerful

Never experienced it myself, but it certainly matches the symptoms. If I were the OP I'd cancel the pump order. and buy a thermostat. If it overheated again I'd fit it. Mike.

Reply to
Miike G

Which van? I've seen a loose water pump impeller behave like that.

Reply to
Duncan Wood

I dont think it's the head, as the water level hasnt changed.

Suzuki Supercarry.

Thanks for the replies. Alan.

Reply to
A.Lee

That has probably got the pressurised coolant system with an unpressurised header bottle (which is common on Jap vehicles, so it is possible to have low coolant in the engine but the bottle level stays the same. get the gas test done, no coolant change does not prove the head gasket is OK, I have changed head gaskets on those, also there is a tiny core plug under the cam that gets holed if the coolant is not regularly changed.

Reply to
Mrcheerful

I've not seen a system where the thermostat regulates the coolant flow to the heater.

John

Reply to
John Henderson

Saab 900 and 9000. 3 stage thermostat. Wouldn't cause the the symptoms described, but the third setting cut off the flow to the heater to avoid the passengers being burned if/when the engine overheated.

Reply to
Elder

+1. Sometimes it turns, sometimes it doesn't. Z
Reply to
Zimmy

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.