Block Test

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Buckinghamshire
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Hi, I'm new to this site and wonder if any of you good people out there could help with a problem I'm having with my recently purchased 2001 Discovery 2 TD5 ES Auto. I will try to keep it brief.

Purchased car from a reputable local dealer a month ago, a few days later experienced two separate instances of fans coming on after short trips. Checked the coolant level and it was low, topped it up several times and soon realised that there must be a leak somewhere as i was getting through quite a lot. As far as I could tell there were no visual signs anywhere of any coolant and no smell. Took it to a local LR specialist who told me they could find no external leaks but that it had FAILED the 'block test' meaning it had to be an internal leak in the engine. Took it straight back to the dealer and asked him nicely to sort it out as I had been told by specialist that this could mean a cracked head or head gasket = v. costly job! Lo and behold the dealer comes back to me to say that his specialist (not LR) had found a leak in the radiator hose and that it has PASSED the block test. So I now have 2 legit invoices: one saying "Block Test - failed", the other saying "Cylinder Block Test" - No fault found".

So here are my questions. How does it fail and then pass a block test? Is someone telling porkies? I have been assured by the LR specialist that a car cannot fail a block test and then pass one within a matter of days - but equally I have documentation that contradicts this. Are there 2 types (or more) of block test? Has the same test been carried out by the 2 different garages? Has the garage that fixed the problem simply dumped some coolant sealant in the coolant tank as a temporary fix. I have done about 500 miles since the 'fix' and have only noticed in the last few days the coolant level is starting drop again. Does this all sound normal?

Thanks.
 
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Its a bit of a curious title, but a 'block test' examines the integrity of the cylinder block - or more likely causes of coolant loss. 3 main possibilities:
1) Cylinder head gasket failure
2) A cylinder liner that has moved at some point when the engine was being worked on at an earlier date
3) Porous cylinder castings.
Either way, I would suspect that there would be products of combustion gases dissolved in the coolant liquid, and this is easy enough to test by doing a 'sniff' test. This is where a sample of the air above the coolant in the expansion bottle is bubbled through a coloured liquid - if products of combustion are present, the liquid changes colour. Its pretty foolproof.
What I'm saying is pretty generic, but I would keep the supplying dealer well informed of your suspicions - any work on this car will be very expensive.
John :)
 
If the engine is now OK? Then it passed the block test and it was the hose.

If the engine is still using coolant then you still have a problem which could well be internal. And as said above, will be expensive to rectify.

If the test is carried out at different engine temperatures you will get different results.

The block test is used in the trade to "help diagnose" an internal leak.
 
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Well the engine seems ok - no overheating and no fans coming on, needle on the temp gauge never goes above middle. However I have noticed that the coolant level has started to drop again. The question now is, what is normal coolant usage/loss? I have been told that the coolant level should not drop at all if all is ok. Is this correct? Should one expect the coolant level to drop to a certain degree with normal usage? I have also noticed quite a strong(ish) smell when I turn the engine off.
 
there is an optimum coolant level, any excess above this level will be blown out as the engine reaches normal operating temperature.
See where it actually reaches a constant level, if it continues to drop then you may have a leak somewhere, look for evidence near water pump.


Wotan
 
Top up to the Maximum mark on the tank and it should stay at that level. But after work on the system it may have air so it could drop until it settles.

To be honest if you had a block issue you wouldn't have to look at the coolant level, so things are looking good.

Keep a close eye on it and DONT run the engine low on coolant.

What sort of smell?

Keep in mind you may have another small external leak that is drying off with the heat from the engine
 
sorry to drag up an older topic.

td5 discoverys. i own two that i work very hard as trailer tugs and recovery motors. over 5 tonne on drawbar not unknown (dont ask, i know its not allowed).

anyhow, the earlier td5 engines have plastic dowels locating head to block. they melt letting head move in relation to block. gives the pass test/fail test symptom you describe.

i own a garage and repair a lot of landrovers. what you are describing could be a gasket problem. however, the disco i run myself, hardest worked btw, always settles just below min coolant level. defo no leaks. it just likes it there. top it up it down to that level in 10 miles and stays there. for weeks.

sorry i rambling. bit drunked.
 
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