Engine damage?????

[jbgt]

Hi,

Galaxy mk2 1.9 TDi 115bhp.
This piece of **** has been giving me grief for a while. One minute the heaters are blowing hot, next cold - after 30miles I would need to top the water up - maybe 0.5 litre or so 
Flushed the system and a large piece of brown build up came out (finger tip to wrist in length) see photo 
Thought I'd solved the problem but no, it continued. Flushed the system out again this time with a rad flush and seemed to work great - for a day. Then yesterday when returning home the steam smell started in the cabin but no change in the instrument panel temp sensor - stayed at 90 degrees.  Luckily I wasnt to far from home 0.5miles
When i opened the bonnet the short (large) hose see photo had burst 
So after the thesis above what is the likelyhood that the head/engine is banjaxed?
What do I check? 

[jbgt]

....also how many thermostat(s) are in this engine?

[Chrispb]

One thermostat where bottom hose connects to cylinder block just under the alternator, two bolts hold the stat housing.
Once this is removed you can feel the impeller on the water pump is secure.

Rusty colour coolant/water would indicate to me that this engine has boiled over a few times in the past and possibly contaminated, something may have been added to the system to stop a leak or possible head gasket failure.
Split hoses are a bit unusual on these cars but could be a result of excess pressure.

Obviously you need to replace the hose and flush out the system also bear in mind there is a restriction in the small return pipe to the bottle see link below

https://www.fordmpv.com/smf2/ford-galaxy-reference-library/heater-blowing-cold-air-and-engine-overheating-underload-(all-models)/

Also auxiliary coolant pump for operation.

[jbgt]

thanks for the reply.

System was already flushed with water and rad flush prior to the pipe bursting.

On examining the other pipes i found that the return pipe to the expansion tank with the restrictor in it has been 'cut off' but i have had the car for 4yrs without the hot/cold issue appearing.
What is the purpose of the restrictor in the pipe? Is it a necessity?

If I buy a replacement pipe for the burst one what are the things to check first upon refilling the system?
How will I check to see if the head has warped or any other catastrophic damage has occured?

[jbgt]

... i recently replaced the auxillary pump as the bushes had worn out.

[Chrispb]

The restrictor allows a small amount of coolant and any aeration in the coolant to return to the bottle (highest point), with it removed the coolant will follow the easiest path bypassing the radiator not a ggod idea if the rad is already restricted with sludge etc.

As to what to look for once pipes are replaced check the coolant is returning to the bottle, the system is self bleeding but easier if car is facing up hill or jacked up, observe coolant level whilst warming up and cap removed topping up if necessary then replace cap, now take car for a run, heavy load if possible.

There should be no significant rise or fall in level look for any signs that coolant has been blown out around the cap.

On return switch off leave for a few minutes now slowly and carefully remove cap, is there any excess pressure or tendency to bubble over?

[jbgt]

thanks again.

What is the possibilty that of more significant damage such as the head or ....?
If it is likely, should i see water mixing with the oil or a leakage between the head and block?
Not the easiest to see as the engine bay is crammed 

The car is the family taxi and i dont wanna be stranded anywhere 

[Chrispb]

It's not that common to have oil in the water and vice versa, or visually see anything from the outside, what is common is excess pressure building up especially after a run.
This is caused by combustion gases leaking across the gasket into the waterways that surrounds each cylinder.

Cracks in the head are not unheard of but more likely gasket failure, only once the heads off can you determine if the head needs refacing (skimming).
Engineering companies that specialise in engine remanufacturing rebuilding can measure for warp and erosion caused by the gasket failure and indeed whether the head is suitable to be refaced.

[jbgt]

Cheers, a wealth of knowledge.

Should i drain the whole system, disconnecting the lower auxillary hose under the car (under the rear passenger seat) before refittind new hose  ?

Should i also change the thermostat, as i was suspecting this of the hot / cold issue  ?
Maybe it is nothing to do with it 

[Chrispb]

No harm in changing stat but more importantly check pump impeller while it is out.
Stick your hose pipe up the two pipes under the car to flush out the rear heater

[jbgt]

Thanks again 

One last thing, is there is an issue with the impeller how can I fix/change?

[Chrispb]

Early mk2's had a plastic impeller which came loose on the shaft if you have a metal one you should be ok.
You can see and feel the impeller once stat is removed but if you decide to change pump it will require removal of the timing belt.

[jbgt]

Will check with the garage that installed timing belt kit work to see if they checked/changed the impeller but I will check myself when the stat is out.

You've been a great help,  

[SilverBeast]

If they replaced the water pump when they did the timing belt then it is probably on your invoice for the work.

As the impeller is part of the water pump (it pushes the water round the engine, just as the fan blades push air through the radiator fins) it would also have been changed.  The issue is if a water pump with a plastic impeller is used, instead of one with a metal impeller.

As stated if you are removing the hose that goes into the bottom of the engine (this goes into the thermostat housing on the 130, not sure about the 115) then with the thermostat removed you can feel the impeller with your finger.  You should't be able to turn it as it is driven from the timing belt and you'd have to be able to turn the whole engine with your finger (I know I can't do it!!).  If it does turn, the impeller is detached from the shaft and the water pump will need replacing - probably along with the timing belt and tensioner.

[jbgt]

thanks for the info, weather permitting I'll get at this job/check in the coming days