3 replies to this topic

[frogs]

Hi, I've noticed today that I'm not getting any hot air from the heater. Someone suggested to me that the water pump has packed up, but I'm reading other things like heater matrix/blocked hoses. 

How would I go about testing the pump or matrix to find out which it is? In the meantime I'll make sure there's no hoses blocked!

I've recently put a new stat in so that should be fine.

 

I drive a 98 Cooper Sport which I believe is an MPI?

 

Thanks, Dan

[RedRuby]

If you have recently replaced the stat, the chances are that you have got an air lock in the heater matrix after refilling the system. Try either disconnecting a heater hose in the engine bay and using a hose pipe pour water into the hose to force any air through and/or start up and let the car idle with the radiator cap off to dispel any air in the system, compressing the top hose when the stat has opened may also help. I'm presuming it is not overheating as you only mention cold heater?

[cal844]

as above, fire the car up (take it a short drive (approx a mile)) to let the engine start to heat but not pressurise the system, then when back home take the rad cap off and let the car idle for half an hour... works every time for us... we also flush the system fully when we do any work to the coolant system#

[frogs]

Ah well, when I let it idle a couple of weeks ago it did start to boil not long after the fan kicked in, when I switched the ignition off it did force its way out of the expansion tank. That's when I was advised it may of been the water pump. However, I've tried idling it a couple times since and it hasn't overheated, and took it out for a spin today and while I did hear a minimal amount of hissing around the expansion tank, it wasn't boiling at all. 

 

Thanks for your replies, I'll take another look tomorrow