diagnosing overheating problem

[J_Dub]

Not a 4wd but the Mrs caldina has started overheating.

Saw rad cap n hoses were well old so replaced them as part of a full service I done yesterday which it was overdue for, it started overheating before the service, both top n bottom hoses r hot so I guess that means flow is not restricted right?

Where would I start to check problem?

Radiator seems fine though there is some discoloration after a flush, water brown again, hoping its not oil, oil still clean after the service.

Cheers

[derk]

is it using coolant or just running hot

[mudlva]

dont know about the caldinas but worth mentioning anyways

the commi 3.8 runs a steel water pump impeller and corrodes away to nothing but a small center disk, which i found out after it had done a h/g.

found out that they were pron to doing this even when running the correct antifreeze mix as well.

so for the sake a a w/p gasket it may be worth pulling the pump off to inspect just in case

[J_Dub]

Just reading "off the clock" hot after 5 mins driving. Doesn't seem to be using coolant.
I'm a bit suspect of the color of the coolant tho, it looks an oliy brown but it's not oily to touch, must just be corrosion?

When the Mrs overheated it I popped the bonnet to find a leak coming from what I think looks like the heater host flange to the water pump, tho yesterday once it ran hot there were no leaks anyway....

Yes I'm thinking the water pump needs to come out too

[Crash bandicoot]

thermostat jammed shut
Radiator cores blocked with rust scale
waterpump had it .

take the top hose off shove the garden hose in the radiator inlet and start it up and see how much water the water pump is pushing
Dont force the water into the radiator though, just let it spill out allowing the water pump to draw in what it needs

[mudlva]

thermostat jammed shut
Radiator cores blocked with rust scale
waterpump had it .

take the top hose off shove the garden hose in the radiator inlet and start it up and see how much water the water pump is pushing
Dont force the water into the radiator though, just let it spill out allowing the water pump to draw in what it needs

take into account the thermo is closed so not a lot will happen as the water will just move around the engine until the thermo opens

[3VILC]

I'd say if you clean it right out and it turns s brown again some things rusty, since there's not a hell of a lot of steel in a modern engine except the block which shouldnt rust if its had antifreeze in I'd pick as above the water pumps impeller has converted itself to rust Your probably going to wish she brought a Hilux, FWD water pumps are generally not a particularly fun job haha. When I did the ex's Corona you have to just about have to dismantle half that side of the engine to get it off

[evolution02]

Do the radiator fans turn on when it gets hot?

[Team Tonka]

When you overheated it with the leaking hose you probably ruined the thermostat. I'd go for that next.

[J_Dub]

Cheers guys. I guess next thing is check water pump

[derk]

Just reading "off the clock" hot after 5 mins driving. Doesn't seem to be using coolant.

is it actually running that hot after 5 mins or just reading that hot on the temp gauge if the temp gauge is reading off the clock it should be spewing coolant out into the overflow bottle and generally giving everything a good old boil up

[J_Dub]

Yea slight exaggeration there, gauge goes right up to above 3/4

[Ant]

You should be able to check the water pump without puling the whole thing apart. Not sure of the exact procedure but could you run the garden hose in the top hose and have the bottom hose disconnected. The flow of water will change when the water pump is "pumping". It might be the other way around too so when the water pump runs the water is pushed the other way so be careful you don't run it dry. You would have to remove the thermostat too.

Also, make sure the radiator isn't to blocked up. again you could put the garden hose to use and run it from top to bottom and from bottom to top, its not going to be conclusive but might give an indication.

Also make sure the fan is moving air, hold a cloth or paper in front of it.