overheating again and again

[evilution1x]

Hi everyone
Please please help.  
My 1.8 tdci galaxy 2008 started to overheat.  
I got the ignition off asap with the hope of saving as much as possible.  
I took it to my local garage and they said my head gasket had gone and it would be Ã,£800ish to get fixed.  
They said my water pump was noisy so that was replaced with timing belt at the same time.  
All seemed fine but 1200 miles later and the first longer journey,  it overheated again. .
So it went back and they skimmed and crack tested the head again. The rad was 70% blocked so it too was replaced.  They then said it needed a new thermostat, so that too was replaced.  All seemed ok, 1800 miles layer, overheats once again! !!! I have a 22 month old daughter and I only have this vehicle as transport.  The idea of it happening with her in the cat on the hard shoulder of a motorway is scary.  Please can someone Advise me of what to do next.  

Summary:
Overheated but fine on idle.
Head skimmed, new water pump, new timing belt, new header tank cap. 
Overheated again but fine on idle.
Head re skimmed, new radiator, new thermostat.
Overheating again but fine on idle. 

Help! Thank you.   

[insanitybeard]

Assuming the work that has already been carried out was done so correctly, it sounds like there could still be some kind of blockage in the coolant system preventing proper coolant circulation, especially if the radiator required replacing due to being blocked (which happens if the engine overheats and deposits on the surfaces of the cooling system internals are dislodged). When it overheats- is it simply that the temperature gauge rises above normal and you stop before anything else happens or does coolant and steam escape from the header tank?

[SiC]

Im surpised the thermostat wasnt changed along with the water pump after the first HG failure.

I would suspect the heater matrix could be partially blocked (for the same reasons as the radiator) ...do you get good heat from it when set to high?

If the HG has gone again so soon after then your either unlucky (dodgy gasket) or you have a leak somewhere causing the cooling system to pressurise to the point its forcing coolant out the header tank.

The EGR cooler could have an internal leak causing coolant to escape via the exhaust and you wont see a noticeable sign of any leakage in the engine bay. Your looking over Ã,£650 for a replacement if it is that (i speak from personal experience).

How often do you check your coolant level?  Have you noticed the header tank looking low but when you release the cap the level comes back up as pressure escapes?

[evilution1x]

Thank you all for your replies. 

The egr cooler was pressure tested first time around.
The heater matrix is not that great and goes warm only when the engine overheats.
When the engine overheats and pulls back (limp mode??), there is a massive pressure in header tank and comes out of overflow only when I release the cap. 

Should I check any pipes, block or matrix??

Thanks loads
David

[SiC]

When the engine is at running temp check the upper/lower radiator hoses, if they are both hot you know the thermostat is working fine.

Next check the temp of inlet/outlet hoses to the heater matrix where they enter the bulkhead (a bit awkward). Both should be hot to the point they are uncomfortable to hold.

If you find one is hot but the other is cooler theres a good chance your heater matrix is partially blocked restricting flow (which also explains the lack of heat when set to high). 

The solution would be to back flush the heater matrix. Some people just use normal tap water via a hose connected to the outlet, others buy a solution designed for the job that breaks down the blockage.

Unlike other cars there is no water valve in the mk3 so the heater matrix is a permanent part of the coolant system.

FYI - I was quoted around Ã,£650 for ford to fit a new heater matrix.

[evilution1x]

Thank you SiC
I am having the HG done again under warranty as we speak, when it is done I will check those things before taking it away. 
Thank you again! !

[SiC]

Your welcome. Hopefully this is the last issue you have with it.

Maybe worth asking the garage to back flush the heater matrix whilst they have it in.  They may already plan to as part of the work but no harm asking as bleeding the air out of the cooling system yourself if you did it at a later date is a pain in the backside.

[evilution1x]

Hi all
The garage have eventually got the head off and are now saying there is  a low point in the block face!! Seems a wee bit questionable as it's steel.    What the general thoughts with that?
They are now telling me I need a new engine!
Vbr
David

[Chrispb]

If it's the actual face I would say unlikely unless there's a mirror image on the gasket or head, what is more usual is erosion around the top edges of the water jacket reducing the surface area between the waterways.

[evilution1x]

Hi. 
Thank you for your reply. 
I'm not really sure what you mean, could I take some photos and post them on here to see if you can see anything?  If that would be ok,  what area would you like to see photo of?
Vbr David

[Chrispb]

Some close up pics of the block face and cylinder head face would help.
An engineering straight edge and feeler gauges can be used to check distortion and warp.
When placing photo's on the site use the full size inline option, see below.[attachimg=1]

[evilution1x]

Well here goes. 
Thank you for all your help chrispb!!![attachimg=1]

[evilution1x]

[attachimg=1]

[johnnyroper]

You can clearly see cause of the over heating,or is that a consequence of the overheating causing gasket to blow between combustion chamber and water jacket.

There is no pic of block on there,personally I can't see a "low point" on a cast block,I would be more inclined to think head warped as it is alloy.
Firstly you need to get a straight edge on block as to cause that damage it would be obvious if there was a low point,then get head checked by machining company.

[evilution1x]

The block

[evilution1x]

Hi Chrispb
Just posted photo of block. 
They told me the block and head was steel. Is that not true?
Head has been machined twice now, the second time it was crack tested to eliminate that potential cause.
How would you clean and check block head without removing from the vehicle?
Vbr
David

[evilution1x]

Hi Chrispb
They told me the head was steel, is that not true?
Head has been skimmed twice now and crack tested on the second time round to eliminate a potential cause. 
How would you check the block without removing from vehicle?
Vbr
David

[johnnyroper]

Use a scraper to remove residue then some wet and dry gradually going down the grades until block face is nice and polished.
Then get an engineers straight edge to lie across block,use feels gauges to see if any fit between block and straight edge along its length. That will give an idea if there's a low point also once clean you will see if the metal around bores etc is eroded.

Was head machined for defo or the garage just said that? The head certainly looks alloy to me not steel.

[johnnyroper]

How long ago was head machined last time?

Assuming everything was done properly last time machining,gasket,new bolts and torquing etc then it sounds like the gasket damage is a consequence of over heating and not a cause to me.

Need to check block if ok go back to basics head check and skim, all new bolts and gaskets,new thermostat and water pump. Back flush and flow check of rad and heater matrix and once up and running bleed all air out and check cooling fan operation.

[insanitybeard]

The 1.8 Lynx DI diesels and the later TDCI's both had cast iron blocks and heads.

It may just be the picture but the coolant visible in the water jacket of your engine block doesn't look a very nice colour to me- it looks rusty, which if actually the case, isn't a good sign.

[evilution1x]

Hi Chrispb
Head was done December 14 and again in July 15.
(I only use the car daughter is in cart with me as it has isofix, my van doesn't, hence small mileage within those months)
Water pump was done on the first time.
Thermostat and new radiator fitted the second time.
Do you think they haven't flushed the system and that's why the rusty water?
Vbr David

[Chrispb]

Hi Chrispb
They told me the head was steel, is that not true?
Head has been skimmed twice now and crack tested on the second time round to eliminate a potential cause. 
How would you check the block without removing from vehicle?
Vbr
David

Yep cast block and head on the 1.8 engine, if the heads been skimmed twice I would think it's on its limit

can see the evidence of blowing across the gasket but actual faces don't look to bad.

Really important make sure the block threads are clear with no oil or water or other debris in the bottom

Use new bolts if not replaced before, check the bolts screw all the way down.

[Chrispb]

Hi Chrispb
Head was done December 14 and again in July 15.
(I only use the car daughter is in cart with me as it has isofix, my van doesn't, hence small mileage within those months)
Water pump was done on the first time.
Thermostat and new radiator fitted the second time.
Do you think they haven't flushed the system and that's why the rusty water?
Vbr David

A cooling system should always have the correct amount of coolant/antifreeze mix, rust and scale can be the result of a diluted mix when topped up with just water.

[evilution1x]

The water top up was probably me trying to limp it home and stopping, cooling and adding water to get just 1 mile.  Gave up and got towed in end. 
I will try to clean the block and use a straight edge to check.
However if the head can't be machined a third time, I'll need new engine anyway? ?
As I've been told, the heater matrix is a constant part of the cooling system, if this is partially blocked, could this cause the overheating and thus the head gasket ?
Vbr David

[Chrispb]

Iv'e never known a head to need skimming twice in a short time like yours, as to whether it could be done again really depends on how much metal has been removed.
If it has distorted that much I would say it's down to the tightening/torquing method used and/or unserviceable head bolts.

The heater matrix is a constant flow (no water valve) but should not affect engine cooling and certainly not cause overheating

[mike wilson]

Use a scraper to remove residue then some wet and dry gradually going down the grades until block face is nice and polished.

I really, _really_ wouldn't do the second part of that.  Doesn't need much carborundum powder to wreck an engine completely.  Copper pipe, flattened to a chisel shape, should be all that's necessary.  Make sure there's no crust on the edges of water galleries.

It's difficult to tell from the photos but the head doesn't look as if it's been cut at all.  My suspicions for the repeated failure would be poor preparation, poor torqueing of head bolts (either wrong spec or pattern) or a head warped beyond repair.

Another, faint, possibility is that you lucked into either a dud run of head gaskets or there are different types of (apparently identical at a cursory glance) gasket for different iterations of this engine.

[johnnyroper]

Doing it correctly with wet paper and then cleaning off after done it that way for years and never had a problem. Just make sure oil and filter is changed after.

I agree about head though it does not look like it's been machined from pictures

[mike wilson]

Changing the oil and filter won't deal with the stuff that's gone into the cooling system, although that will have less overall effect on the motor.  It won't stop it stuffing the oil pump, which drinks unfiltered oil from the sump.  I'm also not sure how you would clean any out that fell between the piston and bore.

In my opinion, there's no correct way of using loose abrasive on the internals of an assembled motor.

As a secondary issue, wet and dry will remove block metal as happily as gasket remnants.  If you really want a low spot on your block face, rubbing at it with abrasive paper is a pretty good way to obtain one.

[johnnyroper]

I beg to differ it is common practise in motor trade to clean the faces in fact it is was also mentioned on the TIS at Vauxhall,I can't imagine a manufacturer would recommend it if it caused damage. I am not talking attacking it with an electric sander just by hand with a block.
I also can't see how you would get enough force on it to put a low spot on cast block either? Personally I prefer to have nice clean mating surfaces when doing a gasket,in my time in motor trade I did more head jobs than I can remember and never had any come backs.
Oh well each to their own I suppose

[johnnyroper]

Just to add I am not talking course grit papers here either just fine stuff used with some wd40 to make sure it is clean and polished.

[Chrispb]

I must say from my time working in a garage etc it was common practice as you describe johnnyroper, what was important was to know when to stop.

[mike wilson]

I just find the thought of putting loose particles, of the second or third hardest substance known to mankind, into a motor abhorrent.  Only with the greatest care in application and cleanup would you avoid all contamination.  Hand on heart; which commercial enterprise has the time to allow that?  While your hand's there; how many "common practices" do you find abhorrent?

I've never been baulked by gasket remnants by using a combination of soft scrapers and chemical removers.