General Overheating JTD 1.9

[dwhyte14]

Hi all,

My 1.9 JTD 80 Stilo temperature gauge started getting towards the red mark today.
It normally sits right in the middle between cold and hot.

It started getting hotter the faster I went and the more revs.
Pulled in to a services and stopped, checked for anything obvious, found nothing.
When I restarted, it all went back to normal and has been ok since.
Revs were not up and was very smooth in 5th gear.

Was motorway driving but only doing a steady 60-65 as traffic was bad!

The only things done recently were the timing belt replaced a couple of months ago and new tyres yesterday.

Since the timing belt was done, when I turn the engine off there is a noise from the engine that sounds like a vacuum cleaner shutting down if that sounds understandable
It lasts about 5 seconds. Didn't think it was a fan but maybe...:idea:
The noise was never there before.

Anyway, any ideas?

Cheers

 

[cheddar]

overheating is usually the thermostat or water pump. I would go for water pump as this is a recommened item with some belt changes. The new belt can overstress the old pump and cause it to fail. As it fails it will make strange noises - the one you describe sounds like the pump slowing down once the engine is turned off. Not good news for you but best speak to the mechanic who done your belt - he should know your car by now and could help guide you towards determining the exact cause of your fault.
I take it you have checked coolant level etc and all is as it should be?

 

[john55]

Water pump impeller fell off. Common on JTD's.

Remove Cam belt again and change water pump.

Dont drive or start it. You risk destroying the engine if the cam belt comes off.

 

[dwhyte14]

Ok thanks,

If it is the water pump, should the garage not have told me it needed changed when the cam belt was done?
Or is it one of those things that could have happened anyway and its just a b**ger that it happened not long after the cam belt change?

What models of Stilo need the pump done at the same time?

 

[john55]

There is no official Fiat requirement to change the water pump with the cam belt, but experience says that it is always a wise thing to do on any car, particularly a JTD.
To change the water pump when the cam belt is already off is very easy and cheap. To change it at another time involves the same labour as a cam belt change.

 

[paulbennet]

overheating is usually the thermostat or water pump. I would go for water pump as this is a recommened item with some belt changes. The new belt can overstress the old pump and cause it to fail. As it fails it will make strange noises - the one you describe sounds like the pump slowing down once the engine is turned off. Not good news for you but best speak to the mechanic who done your belt - he should know your car by now and could help guide you towards determining the exact cause of your fault.
I take it you have checked coolant level etc and all is as it should be?

I have a major overheating problem on a 1.9 JTD 2004. Tried fixing it by replacing water pump (& timing belt), bled the air etc. When testing car lasted maybe 20 minutes longer than before but still overheats with coolant fluid bubbling like mad. Fan is working but doesnt stop temp gage going into red (then engine fault message comes up etc). Spoke to my mechanic who said theres nothing else he can do? Im really stuck and really not sure what to do!

 

[ABZSTILO]

Assuming the thermostat is OK ( is it? has it been changed? ) then that sounds like a right pain the derrier You might try a thermostat bypass - just to see if that cures the problem, it's not a long-term fix.
Has the radiator been thoroughly checked out and the whole coolant system (including the heater system) been drained, flushed and refilled?
Any evidence of a weak coolant pipe?
Any white 'goo' in the oil cap?
What colour is the engine oil - any sign of coolant contamination?

All worth considering IMHO

 

[keviwal]

I have a major overheating problem on a 1.9 JTD 2004. Tried fixing it by replacing water pump (& timing belt), bled the air etc. When testing car lasted maybe 20 minutes longer than before but still overheats with coolant fluid bubbling like mad. Fan is working but doesnt stop temp gage going into red (then engine fault message comes up etc). Spoke to my mechanic who said theres nothing else he can do? Im really stuck and really not sure what to do!

hi,

Could be the thermostat sticking?
http://www.shop4parts.co.uk/?name=store&op=Details&ProdID=4467&sku=10974
The only other thing could be a blocked radiator, or somewhere else in the cooling circuit.
head gasket could have gone where it it boiled before?
Other option could be the temp sensor gone skyward

Cheers,

Looks like ABZ and i are on the same track !!!!!!!

 

[Davren]

bled the air etc.

How many bleed screws did you find? and did you bleed them all in the correct order?

 

[paulbennet]

Thanks for the advice guys. Im not giving up just yet and God willing will try to solve the problem using the advice already given i.e revisiting the thermostat etc. To be continued.....

 

[Deckchair5]

Do some easy stuff first. You can't see the water flow but you can feel it so use your fingers

FIRST CHECK
heater circuit
Start engine from cold-heater fan off
Feel the heater flow and return pipes. Are they both getting hot soon after starting? If either are cold then you have poor flow there or air lock

SECOND CHECK
Is there flow through the radiator?
Is the radiator getting hot? Feel top and bottom hoses as engine warms up. If top hose suddenly gets hot and bottom hose gets very warm then you have radiator flow, no air locks in radiator, water pump is working and thermostat is working
If any part stays cold and your dash temp gauge goes above N then you've found where the problem is and why your car is overheating without even opening your toolbox

WARNING
remember the rad fan can start at any time, even with ignition off, so watch your fingers

 

[dwhyte14]

Update:

The intermittent overheating has become standard now at speeds of 40+ and the other day it went totaly into red and stop engine warning.


Needed a service anyway so had car in at a different garage from the one who fitted my timing belt.

They think either thermostat or water pump and suggested thermostat change as that would be cheap.
Turns out the thermostat on a JTD 1.9 is over £100+VAT for a fiat part
Said yes to fitting it.

Is that a gamble or should I have said no and still suspected the water pump and taken it back to the garage that fitted timing belt?

Car doesn't overheat in traffic queues or at town driving speeds.
Hot air comes into cabin when driving at speed and heater on.
No real outward sign of overheating and if stopped for 5 mins after overheating warning, can drive away and temp gauge goes back down to 3/4's.

Thanks again

 

[ramborobert]

If you see the coolant bubbling theres a problem and don't think it would be the thermostat more likely the water pump or a blockage perform the above checks.

 

[dwhyte14]

Thanks,

Coolant doesn't bubble.

 

[dwhyte14]

Further update:

Had thermostat changed. It's a bugger on the JTD apparently and expensive!
Still showing overheating though with new thermostat it seems to cool quicker.
When temp gauge goes up there is no sign of steam or physical overheating from engine

Took it back to original garage who fitted the timing belt and they still insist that I don't need a new water punp as they should last for ages. Car has only done 43000 miles.
They think it could be electrical like a sensor at the radiator or the connection to the dash panel.

Garage who fitted thermostat said it is a complete unit with new temp sensor.
So there should only be the sensor at the thermostat/rad and the connection to the dash panel? Is there any other engine temp sensor that could be playing up?

They also suggested I get the original garage to check the timing belt to see that it is on right and not out by a couple of teeth. Could this be the problem?

Thanks again

 

[Ffoxy]

Has the coolant system been pressure tested? The whole cooling system is pressurised to raise the coolant boiling point, if there is insufficient pressure in the system through a tiny leak the coolant will overheat.

 

[dwhyte14]

As far as I know it has during the service and thermostat fitting. Will double check.thanks

 

[Ffoxy]

As far as I know it has during the service and thermostat fitting. Will double check.thanks

Seriously... I doubt a pressure test will have been done at Service time, unless you specifically requested it. Ditto when the Thermostat was changed, time is money in a garage. You could have a tiny leak somewhere that doesnt drip coolant when you stop because the system has no pressure, & you just dont see the coolant level drop, or have you had to top-up at all?

Pressure testing will reveal a start point to delve deeper into this as all the obvious points have been mentioned already. Do you use a 50/50 coolant to water mix by the way... or mainly water? I ask because the coolant contains a corrosion inhibitor, if the car is run on a weak or non-existant coolant mix the radiator or heater matrix may be blocking up restricting coolant flow back to the radiator.

 

[dwhyte14]

Never seen the coolant level drop at all.Checked it loads of times but has always stayed at Max.

As far as I know, it is a 50/50 mix, looks like coolant anyway, bright pink colour

Will ask garage about pressure test.

 

[dwhyte14]

Well, still no physical sign of overheating.

Garage have had it for a couple of days and found a fault with diagnostics machine.
Temp sensor to the dash panel error which they have reset and say no more temp gauge going up.

They have also just found a leak from a coolant pipe that runs across exhaust manifold. The water coolant housing is dripping coolant onto the oil filter.
Now the coolant has dropped in a couple of days from MAX to MIN, which wasn't happening even when temp gauge went into the red.
This 'may' have just happened as a co-incidence
This wouldn't have anything to do with the change of thermostat would it?

New thermostat fitted at £200 which probably wasn't needed.
Should garages not put the cars on a diagnostic machine and test coolant system as a matter of course when told car is overheating?