water pump

Post by **sidsmith** » Fri May 12, 2006 9:40 am

I have fitted a water temp' gauge to Mungo, and when I take him out for a spin the needle on the gauge goes off the clock/gauge and he's over heating
there's plenty of water in the radiator and I don't think it's blocked so could it possibly be that the water pump has packed up (there's no rattles or anything) or could it be something else. The gauge is wired correctly so I don't think that that is the problem. one day i'll get used to the so called combustion engine, bah ...bah

Post by **Willie** » Fri May 12, 2006 9:52 am

Elsewhere on this forum you say that you have just fitted a new thermostat
so the obvious question is, did it overheat before you changed it? If yes
then have you refitted the fan belt to a proper tightness. If no then you have
done something wrong or the new thermostat is faulty. Presumably you are
running the supply for the temp gauge from the light green wire at the rear
of the speedo and, if this is so, it could explain your other problem with the
indicator lights on the speedo i.e. you could have replaced the bulb holders
in the wrong places on the speedo as suggested by Chicken John in'electrical'

Post by **bmcecosse** » Fri May 12, 2006 11:28 am

Sounds like faulty gauge (or stat) to me ! If it's not obviously boiling or losing water - then not much wrong. This has only started since you fitted the gauge ? then look to the gauge! Check it with a glass bulb thermometer in the rad.

Post by **Packedup** » Fri May 12, 2006 1:02 pm

Possibly a stupid question, but is the guage wired through a stabiliser?

If not, and the charging system is working well (or even too well!) then the needle will rise more than it should - They're mostly designed for around 10v, although someone posted here about guages with built in stabilisers a while ago...

Post by **sidsmith** » Fri May 12, 2006 7:20 pm

hi, the car was overheating before I put the gauge on. It is wired from the starter switch as I haven't got a voltage stabiliser on the back of the speedo,
It wires from the starter switch to a stabiliser on the back of the gauge , then to the gauge and then from the gauge to the sender unit. I have today also took the hoses off the radiator to make sure it isn't blocked, I can force water through it easily so I am at a loss as to look for next.
sid

Post by **Packedup** » Fri May 12, 2006 8:26 pm

If you pull a hose and spin the engine over you should see healthy pulses of water pumping out. If not, then there could well be a water pump problem.

Also does the system pressure up very quickly with the engine running, even when the coolant is stll cold? Could be blown gasket (or worse, crack between water jacket and cylinder).

Also double check silly things like rad cap - Over time the springs can get weaker, causing the system to blow off steam in a manner very similar to overheating.

And make sure the temp guage is only getting 10v from whatever stabiliser you're using - If it's more (or less of course) then you'll be getting very erroneous readings which won't help!

Post by **newagetraveller** » Fri May 12, 2006 8:47 pm

Is the radiator in good condition?

If some of the little cooling fins have rusted away it may overheat.

Post by **bmcecosse** » Fri May 12, 2006 11:07 pm

How did you know it was overheating before fitting a gauge ? Was it actually boiling up ? Assuming the stat is now ok - then it must be cracked block/cracked head/leaking head gasket - in descending order of expense!

Post by **sidsmith** » Sat May 13, 2006 10:40 am

the radiator isn't boiling over or giving off steam, but with the heater switched off in the car it gets really warm in there, perhaps it could be a duff stabiliser or the wrong type of wiring i've used. there's no oil in the water and the oil level stays constant on the dipstick measure. The performance overall is good , the mpg could be better, so I think i'll have to buy another stabilising unit and try that next just to make sure and then a new dial. If I can sort the problem I will let you all know as it's getting to be a bit of an enigma.
cheers sid & "Mungo"

Post by **newagetraveller** » Sat May 13, 2006 11:44 am

When you say that the heater is switched off in the car do you mean that the electric fan is switched off or that the valve at the back of the cylinder head has been shut off?
If the valve at the back of the cylinder head is still open then the car will get hot in this weather.

Post by **bmcecosse** » Sat May 13, 2006 3:31 pm

Aye - water still circulates through the heater rad - this is a good thing! Don't shut it off if you can possibly avoid it - leads to silting up in the heater. If it's too hot in the car - use the climate control system

ie - Open the quarter lights !