2.5 DSE - Cracked head without overheating ?

mcapinha said:

The radiator is heating evenly now.

I have no experience in sniff tests, can someone tell me how they work ? Do you have to test the vehicle with the engine running or do you just need to test coolant that may have been exposed to HG failure ? If you need to have the engine running I'm thinking that the problem may not reveal itself since it seems to overheat just under heavy load.

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I'm sorry to say that is typical of a cracked head, only shows with high combustion pressures.

Datatek said:

Unfortunately, experience shows that pressure testing does not always find a cracked head. It needs to be done with the head off under high temperature and high pressure to be sure.

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True you can do it with a hot engine too, obviously not boiling. My point was if no gas doesn't mean hgf is out as there are other crevices ..

I think you should take it back where you got the hg done get them to check your car if they don't want to or you don't want the grief.option 2 to get it tested by professionals if the car is not worth much and you can't afford the hassleand it's not worth it then I suggest option 3 £9.99 k seal works wonders for cracked heads and blown hgf I've used it in an old van not worth spending on and to my knowledge its still going ....

defender300td1 said:

I think you should take it back where you got the hg done get them to check your car if they don't want to or you don't want the grief.option 2 to get it tested by professionals if the car is not worth much and you can't afford the hassleand it's not worth it then I suggest option 3 £9.99 k seal works wonders for cracked heads and blown hgf I've used it in an old van not worth spending on and to my knowledge its still going ....

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K seal won't seal a cracked head, nor will irontight. Better to replace the head with a second hand one.

That's just it: when I had the head off to replace the HG the head was pressure tested at a high temperature (or so I was told). Since this is something beyond my technical skills and since I also don't have space to work on such a big task, I had it done by a mechanic who told me the head checked out OK. So I'm thinking about doing the sniff test and if it fails the mechanic will have to fix it, so he'll have to troubleshoot if the problem is the head or the HG. Right now I just need a 100% sure way of showing him that the problem is the HG or head.

Datatek said:

K seal won't seal a cracked head, nor will irontight. Better to replace the head with a second hand one.

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You can argue with the manufacture not me
K-Seal will permanently repair most cracks or leaks in the cylinder head where there is coolant loss. You simply shake the bottle, pour and go. It is literally as simple as that!
Want to get hold of a bottle to fix your cylinder head?

defender300td1 said:

You can argue with the manufacture not me
K-Seal will permanently repair most cracks or leaks in the cylinder head where there is coolant loss. You simply shake the bottle, pour and go. It is literally as simple as that!
Want to get hold of a bottle to fix your cylinder head?

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It will fix water leaks in the head but not a crack into the combustion chamber especially round the exhaust valve where they usually fail. The cracks only open under high pressure/temperature.
It may also block the narrow waterways in the P38 RAD.

Datatek said:

It will fix water leaks in the head but not a crack into the combustion chamber especially round the exhaust valve where they usually fail. The cracks only open under high pressure/temperature.
It may also block the narrow waterways in the P38 RAD.

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If that's the case then when its over heating it would be squirting all sorts out the exhaust wouldn't it when crack opens

mcapinha said:

That's just it: when I had the head off to replace the HG the head was pressure tested at a high temperature (or so I was told). Since this is something beyond my technical skills and since I also don't have space to work on such a big task, I had it done by a mechanic who told me the head checked out OK. So I'm thinking about doing the sniff test and if it fails the mechanic will have to fix it, so he'll have to troubleshoot if the problem is the head or the HG. Right now I just need a 100% sure way of showing him that the problem is the HG or head.

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Yep I see well good luck hope they sort it for you if he refuses see what trading standards have to say how many miles have you done and how much time has passed ??

defender300td1 said:

If that's the case then when its over heating it would be squirting all sorts out the exhaust wouldn't it when crack opens

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Nope, the cracks go into the water jacket not into the exhaust and they can be invisible to the naked eye.

The mechanic is a friend of mine that I use to go offroading with. He's been very straightforward about this and if it's proven that the problem is with the HG or head he'll sort it out.
I've already tracked down another garage that has a sniff test so I'm trying to book it to go in Saturday. I'll let you all know how this turns out

Hi,

If it's of any use I've used K-seal and it worked. The engine has done over 10,000 miles since with no problem. If you do use though I would recommend flushing it out once the seal has been made.

Spen, is yours a 2.5 DSE too ?

No, a td5. I didn't think it was the best option at the time but couldn't really afford the repair so took the chance and it worked. However mine wasn't over heating like yours and was only loosing around a litre of coolant during a week....around 250 miles.

I'm by no way endorsing the product as I know lots of people have different views about it.....I'm just sharing my experience.

I have a 2.5 dse that had an intermittent overheating problem when under high load (long steep hills or towing a trailer up a hill), it didn't overheat all the time, only occasionally and it was the viscous coupling.
To check the viscous coupling, run the vehicle till its hot, stop the engine and pop the bonnet. Grab the fan by a blade and spin it. If the fan spins freelly then the coupling is kaput, if it only spins a half to 3/4 of a turn then the coupling is ok. The bearing was also worn in mine so it had a bit of free play when you held the fan blades and wiggled it side to side, and i think that is why it worked sometimes but not always.
It is not too difficult to take off the water pump to check the impellor either, so i would also remove the pump and check it. If it has a steel impellor then it may be corroded and half the blades missing so not pumping enough water. If it has a plastic impellor then these could also be damaged.
Good luck.

Got a call today from the shop that did the sniff test and the result is positive. I'm going down there tomorrow but from what the shop owner told me over the phone, it is leaking very bad. He said that as soon as he installed the testing kit the liquid turned from blue straight to yellow, so there's lot of combustion gases on the coolant. Oh well, time to take the head off, again.