Technical Coolant Leak

[OverheatingPalio]

Had head gasket, thermostat, temp switch and water bottle replaced. after driving about 30 km I stopped and checked water reservoir / bottle. Found foam and bubbling in water reservoir / bottle, can see a little water has leaked out water reservoir / bottle cap. Any suggestions as to what the cause could be ?

 

[fingers99]

Re: Bubbling/water running noises

Had head gasket, thermostat, temp switch and water bottle replaced.

Dumb mechanic!

Chances are they didn't bleed it properly. But foolish not to replace the belt, tensioner and water pump (and water pump O ring) while in there.

Was the head skimmed?

 

[OverheatingPalio]

After replacement of (head gasket, thermostat, temp switch and water bottle) the temp gauge is between 1/4 and 1/2 when driving or idling in traffic.

After driving about 30 km I stopped and checked water reservoir / bottle. Found foam and bubbling in water reservoir / bottle, can see a little water has leaked out water reservoir / bottle cap, you will hear a hissing noise near water reservoir / bottle cap every now and then. Water level in water reservoir / bottle is on (min) mark.

Any suggestions as to what the cause could be ?

 

[fingers99]

Re: Coolant leak

Was the head skimmed?

It would suggest to me that the HG has failed.

 

[Ziggy122]

Re: Coolant leak

After replacement of (head gasket, thermostat, temp switch and water bottle) the temp gauge is between 1/4 and 1/2 when driving or idling in traffic.

After driving about 30 km I stopped and checked water reservoir / bottle. Found foam and bubbling in water reservoir / bottle, can see a little water has leaked out water reservoir / bottle cap, you will hear a hissing noise near water reservoir / bottle cap every now and then. Water level in water reservoir / bottle is on (min) mark.

Any suggestions as to what the cause could be ?

Was the head skimmed?

It would suggest to me that the HG has failed.

Overheatingpalio
Stop hi-jacking every thread going - Start your own topic
It'd be easier to keep track of what you've been told

Ziggy

 

[ChrisUK]

Re: Coolant leak

Moved into his own thread .

 

[MikeSalt]

Re: Coolant leak

OverheatingPalio,

The reason that everyone is asking whether the head was skimmed is due to the most common failure mode of Fiat head-gaskets: localised warping of the head. Head-gaskets rarely just 'go' in these cars, it is usually due to overheating causing the head to warp. As the head warps, it lifts from the block causing separation of the gasket and its subsequent failure. As a result, the head MUST be skimmed since it is no longer a flat surface, and any head gasket installed against this uneven surface will not properly seal and will fail again.

The correct steps to take in the event of head gasket failure are:

Head off
Head skimmed
Block cleaned
Head gasket and head back on
New waterpump and cambelt (the belt has been disturbed, it's worth replacing)
Fresh oil, filter and coolant since these may have become cross-contaminated
Find the original reason for the overheat and fix

The two reasons I have killed a head gasket is from thrashing the engine when not sufficiently heated up and from a faulty thermostat that was not actually letting the engine reach operating temperature (head warping due to thermal stresses). Low coolant level, blockages due to dirty coolant and improperly bled cooling systems can lead to hot-spots in the head too.

I hope that helps,

Cheers,

Mick

 

[s and b]

a head gasket is just a means to seal two components from leaks
see it as the weakest link like a fuse
if caught in time and engine stopped then unless severe mechanical damage has occurred then a simple head gasket change can be a nice cheap solution
ie as soon as needle climbs
you turn the motor off and then find the cause
you dont nip down to sainsbobs in your jimjams and hope it makes it

 

[Ziggy122]

mikey has hit the nail

There is a fualt which caused the HG to fail

By simply replacing the HG it'll temporarily mask the issue before long it's back doing the same tricks

A prime example is the waterpump - works poorly
new HG and pump still remains weak - car gets hot enough and it blows again

Thermostat - Stuck open = Thermal Stress
Stuck Closed - Rapid overheating and thermal stress galore

Blocked heater matrix or radiator = Low coolant flow
And reduced cooling effect - esp if the rad is shot

Ziggy