My 1992 CLX is running much hotter than usual. Climbing to just below the red quickly in traffic but cooling only a little on the move. No noticeable loss of power. Top and bottom pipes are hot, coolant a little low, but no white gunk in the oil.

So I search the forum, read some other posts and then come across a description of virtually the same problem, posted in Sept 2013 ....by me (#sheepish)

Naturally, re-reading the whole thread brought it all back. The solution last time was to replace the water pump (with a solid looking metal vaned one) and flushing the system with the garden hose.

I did it before so I know I can do it again, but I am surprised that the water pump has stopped working after 3.5 years. What could go wrong with it?
There isn't any noticeable noise coming from it and no evidence of leaking coolant on the driveway.

Could I be jumping to conclusions and be missing something else?

Thanks

What was wrong with the old waterpump?
I've only seen three pumping failure modes on this type of pump
Corrosion or erosion of te impeller
Blockage due to contamination or corrosion
Impeller coming loose on shaft

The last is the most likely, IF it's a pump failure.

Robert G8RPI.

Thermostat?

If top hose is hot as OP says shouldn't be t/stat.
You mentioned in traffic it approaches red, coolant fan cutting in and out?

Fan seems to be working fine, kicking in as the gauge goes into the red, and stopping as gauge drops below red

Air trapped in rad?check bleed screw?fill through bleed screw.

change thermostat , it may be opening late or may be not opening enough.
Fan should start before gauge reaches red.
Could be reduced flow flow through rad leading to fan switch heating slowly due to iffy thermostat.

The fan generally kicks in after the first mark just after the needle is straight upwards (can't say the exact dial measurement without looking at my car). If your fan is kicking in when the gauge gets to red, I am wondering if it's the earth fault that others are having at the moment which causes the gauge to advance further than it should.

Other than that, I'd agree with the other suggestions - is your heater matrix getting warm as well?

Thanks. I will open the bleed screws and get rid of any air
I will check if the heater matrix is getting warm
The fan has always started when approaching the red
Will report back
Thanks for the advice so far

The tank at the side of radiator is an expansion tank for coolant. Picture it as a separate tank only joined to radiator by a hose going from bottom of tank to bottom of radiator.
if there is air in radiator fill through the bleed screw holes, small funnel useful. leave expansion cap on or you will end up with no expansion air space in tank.
Ooo casting my mind way back I may have used to fill these systems by removing the top most heater pipe and filling through that pipe. Doing it that way put rad bleed screw back in when coolant free of bubbles flows out.stop filling when coolant comes out of heater stub , make sure heater valve open when doing this.
Good luck.

PS add an extra earth wire from battery -ve to body it works wonders .

Best way I've found to bleed them is to get someone to keep an eye on the bleed screw and use your mouth over the expansion tank and blow putting pressure on the water to go through the system, once air has all come out the bleed screw tighten it up then run the engine and repeat if needed.

Yes as mentioned the fan should switch on just past the midway mark on the gauge and typically turns off just under midway again.
I may be completely wrong here but does the dash temp gauge read from a different sender to the source the fan uses to switch on and off? I feel like I read that somewhere... If so could be the fan sender is out and telling the fan to come on much later it should. Or the gauge side of it is out and the gauge is reading hot when the engine isn't?

On panda mk1 gauge sender and fan switch are separate parts.
Fan switch is screwed into radiator.

Freebo said:

Best way I've found to bleed them is to get someone to keep an eye on the bleed screw and use your mouth over the expansion tank and blow putting pressure on the water to go through the system, once air has all come out the bleed screw tighten it up then run the engine and repeat if needed.

Click to expand...

Don't do this with the engine hot


A radiator leak test kit often contain a cap with a hose fitting. This provides a safer method of pressure bleeding than mouth to expansion bottle.


Robert G8RPI

g8rpi said:

Don't do this with the engine hot

A radiator leak test kit often contain a cap with a hose fitting. This provides a safer method of pressure bleeding than mouth to expansion bottle.


Robert G8RPI

Click to expand...

I only do this when cold, assuming if your bleeding it then the engine isn't going to be hot. Besides if it was I can't see any issues?

Freebo said:

I only do this when cold, assuming if your bleeding it then the engine isn't going to be hot. Besides if it was I can't see any issues?

Click to expand...

The first issue is of course getting hot water blown back at you, examples being a thermostat opening or airlock releasing. You need the engine running to circulate the water.
Other issue is that coolant is toxic.


I have of course never done this myself


Robert G8RPI.

g8rpi said:

The first issue is of course getting hot water blown back at you, examples being a thermostat opening or airlock releasing. You need the engine running to circulate the water.
Other issue is that coolant is toxic.


I have of course never done this myself

Robert G8RPI.

Click to expand...

Hehe. Well so far I've only ever done it on cold engines and not experienced these things. Would be interested in a tool to do this, might make life easier

g8rpi said:

The first issue is of course getting hot water blown back at you, examples being a thermostat opening or airlock releasing. You need the engine running to circulate the water.
Other issue is that coolant is toxic.


I have of course never done this myself

Robert G8RPI.

Click to expand...

Big issue is it tastes disgusting.....I imagine[emoji4]

Don't leave any open containers of it around, bowls you have drained it into etc
Pets and other animals are attracted to it's sweet smell and drink it. It only takes a teaspoon full or so to kill a cat for example. Death from liver failure very nasty.

On the panda mk1 , heater hose fill and bleed method is probably cleanest.

I would say it is the gauge showing wrong temperature.
First red is at 120*C if rad fan kicks in more ish around same place-all is FINE apart from the wiring.
You would not get too far with engine at 120 degrees C.
Iirc stick 2.7k Ohm resistor inline and check the dial indication.

Thanks the help so far.
I am minded to flush and refill the whole system at the weekend.
I'll report back
If the problem is still there after that, maybe replace the thermostat and water pump (and timing belt whilst I am at it)
Hopefully flush and refill will work though

Torridon1 said:

Thanks the help so far.
I am minded to flush and refill the whole system at the weekend.
I'll report back
If the problem is still there after that, maybe replace the thermostat and water pump (and timing belt whilst I am at it)
Hopefully flush and refill will work though

Click to expand...

May I suggest you check for air in radiator being the problem first?
If that's the problem at least you will know.
Flush and refill after that good idea anyway.