06 TD5 Defender using WATER

[mike_beecham]

Hi all

Just a question (may well be silly!). I have an 06 Defender. Had to filll the overflow tank for the radiator up from dead empty about a month ago. Since then - kept an eye on it and it has slowly only gone down maybe 2cm under the 'COLD' level??

It has worked BLOODY HARD over summer (as all our Defedners do) - l am a Hay Contractor and it is not un-common for it to run all day in Low 1/2 pulling 2 tonne of hay about a paddock with the AC on! As well as towing implements on the road between jobs.


Is this an issue or standard? Have cooked one TD5 (Disco) - don't want to go down that pasth again!

Cheers,


Mike

[Blknight.aus]

while it should be above the cold level it doesnt have to be... mark the tank with a line and dont add anyting to it but keep a damn close eye on it if it doesnt move in a month then thats where your engine wants to be...

[Slunnie]

Temps also affect the level a fair bit.

[Blknight.aus]

good point....

cold is considered 25 degrees which is supposedly room temperature...

I forget the formulas for working out the expansion rate of water over temp but the rough reckoner for water is something like 1CC per L per 2 degrees between 15 and 80 degrees...

whats the temp your checking it at?

[davros]

why was the expansion tank empty in the first place??

I have a had worry with my disco that the head cracked at about 150000 and I had the typical dramas and x $k cost.

Everyone says "now the steel head dowels are in it's great" etc...

Just like it was when it was new...

But what happens at 300000? Will the head stuff up again? Is there any real proof the dowels are the cause (I hope so!!), or is there a design weakness in the head and in reality they last 150000 and are very sensitive to high temps, steel dowels or not??

What I'm saying is of course the head is ok on mine now it's new and there's a new gasket and dowels, but I will be intersted to see if this case is a cracked head on a newer model, with the steel dowels?

As an aside, when mine was cracked, temp made a slight difference to the amount it leaked - I guess the crack may twist open or closed.

Hope it's not!!

Dave

[Graeme]

It should not use any coolant - my current TD5 doesn't use a drop.

When my 99TD5 was loosing coolant the LR dealer said they all use a bit. Eventually I discovered that it lost water from the hose connection at the top of the head. The leak was not detectable due to the engine cover being unable to be removed due to a broken captive nut and the dealer refused to damage anything to get the cover off, whereas I took to the bolt with an angle grinder. Subsequently the head was destroyed due to overheating whilst arguing with LR as to who was going to pay to fix it.

My conclusion re the plastic dowels is that they only allow the head to move once the bolts loose their tension due to overheating. If the head moves enough then valves can damage the bores.

I replaced all hose clamps on my 03TD5 before warranty ended as I believe the spring type clamp was the cause of my earlier problems. I heard many years ago that Jaguar replaced all hose clamps on new vehicles in Australia before they were sold because the clamps were unreliable.

[CraigE]

Look if any vehicle is worked hard in hot dry conditions, you will use some coolant. It is a liquid and will evaporate / condensate to some extent. As long as it is not excessive. Look out for tell tale signs like oil in water , water in oil, steam from exhaust or just leaks. Mine uses a tiny little bit when really worked hard, but not much.
A coolant sensor is a great investment. A friend with a 100 series will be getting one after the weekend after throwing both drive belts and ballooning his radiator. He was lucky this was the only damage, would have been much worse if a hose had failed or another few minutes.

[Captain_Rightfoot]

My 05 car was doing the same... ie using a tiny bit of coolant **very** slowly. I as for it to be checked under warranty and they found a very small leak in one of the hoses. They replaced it and it hasn't moved since :)

[Slunnie]

The other time that the coolant level moves around a bit is after it has lost coolant (eg, flush etc) and it has been refilled. Despite following workshop procedure, there will still be some air left in the engine and it takes a little bit to get it all out.

[loanrangie]

Everyone says "now the steel head dowels are in it's great" etc...

I really dont get this statement , you dont even need the dowels once the head is torqued down correctly, i have had a few engines without dowels without any problems ?

[ak]

why was the expansion tank empty in the first place??

I have a had worry with my disco that the head cracked at about 150000 and I had the typical dramas and x $k cost.

Everyone says "now the steel head dowels are in it's great" etc...

Just like it was when it was new...

But what happens at 300000? Will the head stuff up again? Is there any real proof the dowels are the cause (I hope so!!), or is there a design weakness in the head and in reality they last 150000 and are very sensitive to high temps, steel dowels or not??

What I'm saying is of course the head is ok on mine now it's new and there's a new gasket and dowels, but I will be intersted to see if this case is a cracked head on a newer model, with the steel dowels?

As an aside, when mine was cracked, temp made a slight difference to the amount it leaked - I guess the crack may twist open or closed.

Hope it's not!!

Dave


My gut feeling is that with the TD5 the head is the part of the engine that Landrover could not get durability out of way back in the design stage. From what I have read in other Landie forums not just here, if constantly worked hard ( towing big horse floats in hill conditions massive amounts of beach work constantly on super hot days ) the Td5 does not liked to be stressed and evently gets head problems. That's why it seems some Td5's suffer this fate and others don't.

[Blknight.aus]

My gut feeling is that with the TD5 the head is the part of the engine that Landrover could not get durability out of way back in the design stage. From what I have read in other Landie forums not just here, if constantly worked hard ( towing big horse floats in hill conditions massive amounts of beach work constantly on super hot days ) the Td5 does not liked to be stressed and evently gets head problems. That's why it seems some Td5's suffer this fate and others don't.

Shhh dont tell big red that......

[Slunnie]

My gut feeling is that with the TD5 the head is the part of the engine that Landrover could not get durability out of way back in the design stage. From what I have read in other Landie forums not just here, if constantly worked hard ( towing big horse floats in hill conditions massive amounts of beach work constantly on super hot days ) the Td5 does not liked to be stressed and evently gets head problems. That's why it seems some Td5's suffer this fate and others don't.
There was also a heap of effort put into cooling the engine to keep the heat out of it too.

Here is a really interesting read from LROI that some may be interested in. It's about the development of the TD5. My apologies as the article has been photographed, but if you click on the pics you will get a high res copy.

www.slunnie.com - LROI TD5 article (http://www.slunnie.com/coppermine/thumbnails.php?album=135)

[ak]

I won't argue with Dave or Simon you guys have heaps more tech experience than me. It's strange how some Td5's have head problems and others don't. However as said above my best guess is still the fact that it mainly happens to TD5's that work really hard constantly in hot conditions and of-course other factors like wrong coolant and lack of servicing. However I would be interested to hear other thoughts especialy from the likes of Dave and Simon. So keep the thoughts coming guys. Am I onto something hear with my line I thinking? Or not.

[tombraider]

Everyone says "now the steel head dowels are in it's great" etc...

I really dont get this statement , you dont even need the dowels once the head is torqued down correctly, i have had a few engines without dowels without any problems ?

Again you speak wisely :)

[djam1]

An interesting read Slunnie very enthusiastic author telling us about the Bomb Proof TD5??

[B92 8NW]

Everyone says "now the steel head dowels are in it's great" etc...

I really dont get this statement , you dont even need the dowels once the head is torqued down correctly, i have had a few engines without dowels without any problems ?Again you speak wisely :)

Can someone explain the dowels to me? I thought they were just to locate the head onto the block, hence if they were made of steel, plastic or indian naan it wouldn't make a difference? Or am I totally wrong:(

[Sandtoyz]

A way to check if you are losing coolant from the overflow,
put the overflow hose into a plastic bottle of some kind, taped in or similar.
so any fluid coming out of the overflow is then caught in the bottle.

If it isn't coming out the overflow, and your loosing coolant, it must be going elsewhere... just where is the secret question. :confused:

[Blknight.aus]

Can someone explain the dowels to me? I thought they were just to locate the head onto the block, hence if they were made of steel, plastic or indian naan it wouldn't make a difference? Or am I totally wrong:(



nope your tottaly correct...

the dowels are only there for the initial locating of the head and gasket while you put it all together....

So far Every head fault I've personally seen with the td5 (5 now) Has been easily attributable to either operator error OR dodgy workmanship when the operator has taken it to someone to have the required corrective work done.

The big problem with the dowels is when cheapskate mechanics try to reuse the plastic ones the head can be sat on and the dowels will let it sit off center then engine will work for a while but once the combustion process begins to eat the head gasket failure isnt far off.

[feraldisco]

There was also a heap of effort put into cooling the engine to keep the heat out of it too.

Here is a really interesting read from LROI that some may be interested in. It's about the development of the TD5. My apologies as the article has been photographed, but if you click on the pics you will get a high res copy.

www.slunnie.com - LROI TD5 article (http://www.slunnie.com/coppermine/thumbnails.php?album=135)


Thanks Slunnie - yes, it is a very interesting (if a bit self-serving by the author) read. One can't help but wonder that LR went through a very complex process to make a complex motor to account for the requirements of an in-line 5-cylinder that could fit within the Disco engine bay - maybe they would have been better off with the Beemer 4-cylinder TD! Then again, I love my Td5, and better say nice things about it to maintain the amicable relationship...

[Slunnie]

No probs mate. I guess back when they were developing the motor they were still owned by Bae, before BMW took ownership. I guess that's exactly what they did though after BMW scrapped the TD6 and used the BMW TD in the new Range Rover.

[Chucaro]

nope your tottaly correct...

the dowels are only there for the initial locating of the head and gasket while you put it all together....

So far Every head fault I've personally seen with the td5 (5 now) Has been easily attributable to either operator error OR dodgy workmanship when the operator has taken it to someone to have the required corrective work done.

The big problem with the dowels is when cheapskate mechanics try to reuse the plastic ones the head can be sat on and the dowels will let it sit off center then engine will work for a while but once the combustion process begins to eat the head gasket failure isnt far off.

I agree with the observation of dodgy workmanship. It would not surprise me if 70% of problems with Land Rovers in general are attributed to this factor. If the owner is unaware of the bad work done he will keep returning to the same mechanic until he sells the vehicle for being unreliable.
I have to pay twice for work done on the timing belt of the Tdi300 because the job was not done correctly in the first time by a "Land Rover especialist"
His work lasted 20000 km and luckily I found the problem when the belt jumped 1 tooth. I just wonder how many Tdi owners have the same problem with this mechanic? :eek:
I guess that the TD5 is more sophisticated and require more knowledge person to work on it.

[Blknight.aus]

pfaffle...

anyone who wants to do what I can do can do what I can do...

they just have to do what I did...


read books and be prepared to get it wrong a few times then learn from the snafus.

These things come with manuals and those manuals point you to other books on how to do bits that arent explained in the manual...

[ak]

There was also a heap of effort put into cooling the engine to keep the heat out of it too.

Here is a really interesting read from LROI that some may be interested in. It's about the development of the TD5. My apologies as the article has been photographed, but if you click on the pics you will get a high res copy.

www.slunnie.com - LROI TD5 article (http://www.slunnie.com/coppermine/thumbnails.php?album=135)

Getting back to this line of thinking ( thanks for the post Simon very interesting ) if the Td5 is so well cooled why do alot of them keep over-heating? Can't all be down too bad servicing can it?

Leanered tech ones please educate me?

[Blknight.aus]

thats simple,

they are made of a heat treated aluminum and the combustion process can generate enough heat to undo the heat treating, so a very high tech coolant system was developed to deal with it...

Lets start out with coolant concentration your doing the right thing, youve noticed the cooling system is a bit low so you top it up with some distilled water. this dilutes the coolant and eventually it will drop below the point where it can deal with the temp range it needs to be able to deal with.

so like all things hi tech its only got to go out of tolerance a little bit and it wont work as effeciently which leads to a bit of heat build up which will slowly start to undo the hardening. This in itself leads to eventual head warpage. But like all complicated things it doesnt stop there As the head is getting hotter the cooling system gets hotter lets face it if it didnt the laws of physics would have gone on holidays but I digress. As the cooling system gets hotter the coolant expands more, more expansion means more pressure which puts things like your hoses and expansion tank at risk more often than not the extra pressure will just squeeze a little bit of coolant out past a hoseclamp untill the pressure is back under control.. So thats not too bad...Untill the hose develops a permanant leak or untill you loose enough coolant that you have the metal inside the cooling system exposed to air and not immersed.

Now when that happens things go very bad very quickly.

Ok lets deal with the wrong coolant

this is easy the wrong coolant will eat the engine parts through a mixture of chemical reation, electrolosys and scouring. last time I checked removing metal from things that deal with pressure isnt such a cool idea.

And finally neglect.

if the radiator becomes clogged (internally or externally) then the coolant doesnt flow or the coolant doesnt get to transfer heat to the atmosphere.. the coolant gets too hot and then bad things happen, again surprisingly quickly. The same applies to water pumps, thermostats heater elements the whole shooting match, if its not up to standard its going to give problems.

and most of that with the exception of cleaning out heat exchangers and radiators is DIY type inspection and repair work....

[feraldisco]

posts like Dave's make me nervous...did someone say timebomb...

I guess a big part of the problem is that LR crammed five cylinders into a relatively short block and the tolerances of everything seems to be pretty fine..and I presume the block water channels are also small diameter and therefore easily blocked.

I guess, as Dave says, the keys are to maintain cooling systems rigorously and to fit aftermarket temp sensors and coolant alarms...

[Blknight.aus]

the cooling jackets are quite roomy for what it is, (more space in there than in a series block at any rate)

ITs only a time bomb if its abused to hard or neglected.... ITs a PC motor you need to give some loving to and it will love you back. Its not like a series 2.25 which is sort of like the village idiot of engines Abuse it and it just comes back for more.

[Graeme]

Getting back to this line of thinking ( thanks for the post Simon very interesting ) if the Td5 is so well cooled why do alot of them keep over-heating? Can't all be down too bad servicing can it?

Leanered tech ones please educate me?
I would like to know the success rate of re-torquing the head bolts at, say, 100k kms, in the same way as some other vehicles. I'd like to do mine as preventative maintenance but dare not unless its already been establised as successful.
Saab used to recommend it but the recommendation stopped when GM bought it and then head gaskets started to leak somewhere aroound 150k kms. But the Saab stretch bolts can be tightened a max of 3 times IIRC whereas LR say only once for the TD5's - ie the original time. In times gone by, Deutz stretch head bolts could be reused as long at their length didn't exceed specified limits, although being air-cooled they don't have the complication of water passages.

[Blknight.aus]

Nooooooo...

let me say that again.

Nooooooo..

dont touch the headbolts unless you want to replace them...

they are angle torqued not done up to a torque setting and they are not a very forgiving bolt.... (ask Auke)

However they make great tent pegs so if youre going to redo your head bolts can I have the old ones?

If you wanted to replace the bolts as a preventative measure you might get away with undoing one bolt (eventually all in the correct sequence) and installing the new bolt in that hole to its starting torque then when youve changed all the bolts over to the new ones going in the normal tightening sequence...

But If I was going to do that ID also replace the head gasket.

[Graeme]

Nooooooo...

let me say that again.

Nooooooo..

dont touch the headbolts unless you want to replace them...

they are angle torqued not done up to a torque setting and they are not a very forgiving bolt.... (ask Auke)

However they make great tent pegs so if youre going to redo your head bolts can I have the old ones?

If you wanted to replace the bolts as a preventative measure you might get away with undoing one bolt (eventually all in the correct sequence) and installing the new bolt in that hole to its starting torque then when youve changed all the bolts over to the new ones going in the normal tightening sequence...

But If I was going to do that ID also replace the head gasket.
I only kept one for use as a long punch.

In the absence of strong supporting advice, I would just change the gasket as soon as it started to leak.

Did I hear you say No?