Wicklaman
Member
We believe around 150k miles.
It had a new head installed maybe 10k miles ago.
I purchased it 5weeks ago. It has a major rebuild, and is in super condition mechanically. Hence the engine donation from seller to help diagnose issue. He was not happy when i told him about the issue and wants to help resolve. Spare engine is also from good history with 140k miles
discomania
Well-Known Member
Brand new head?
Wicklaman
Member
yes new head. what i don't know is what supplier and if it was a fully assembled head.
there is Mastic/grey silicone around the rocker cover bolts and cyclone. these are the only things i didn't like.
Wicklaman
Member
took cylinder head off at weekend and pressure tested today. crack in an exhaust port. i will have more detail later when i collect from engineering shop. next step to pressure test head on spare engine. the head is not new despite what I was told when I purchased the Defender and is in poor condition with lots of fails around the gasket which is a composite gasket and the exhaust gasket lip was sandwiched between head and block. bit of rust on face of 1 valve. some oil showing on head for 2 cylinders. I have some analysis to do...can upload some photos again. but looks like my initial suspicion was correct. Injectors were perfect, got them cleaned and tested.
i have stripped head from spare engine and it seems in much better condition, in fact so does block and pistons. I may yet decide to swap entire engine now that I am this far in. pressure test on head #2 tomorrow.
first 2# photos of original engine, 2nd 2# photos of spare engine.
appreciate any helpful comments.
Last edited:
Wicklaman
Member
folks more updates.
the head was for sure NOT a new head. if it was replaced recently then it was a USED head. the replacement was not good. gaskets were poorly fitted, studs in exhaust and inlet manifolds were poorly fitted. This is my first head replacement, but utilising the wealth of information available it has been relatively straight forward. i have tested the spare (used head) it is in good condition, requiring minimal skimming. new stem seals, 3 hole metal gasket, block cleaned, injectors tested and cleaned, new exhaust/inlet gasket, new thermostat and housing gasket, rocker cover gaskets, valve clearances checked (twice). Just waiting for oil filter and sump nut and new cyclone and we will be ready to turn key. i may take opportunity to seal sump as there is a little weep. what knowledge can i pass on to others? i would say, take time diagnosing and stick to the facts to lead you to root cause. Also, i made sure to clean out all bolt holes meticulously. i will update again when i turn the key. thanks again Discomania.
the head was for sure NOT a new head. if it was replaced recently then it was a USED head. the replacement was not good. gaskets were poorly fitted, studs in exhaust and inlet manifolds were poorly fitted. This is my first head replacement, but utilising the wealth of information available it has been relatively straight forward. i have tested the spare (used head) it is in good condition, requiring minimal skimming. new stem seals, 3 hole metal gasket, block cleaned, injectors tested and cleaned, new exhaust/inlet gasket, new thermostat and housing gasket, rocker cover gaskets, valve clearances checked (twice). Just waiting for oil filter and sump nut and new cyclone and we will be ready to turn key. i may take opportunity to seal sump as there is a little weep. what knowledge can i pass on to others? i would say, take time diagnosing and stick to the facts to lead you to root cause. Also, i made sure to clean out all bolt holes meticulously. i will update again when i turn the key. thanks again Discomania.
Attachments
jamesmartin
Well-Known Member
what is minimal skimming
Wicklaman
Member
hi Jamesmartin.
I brought head to a well established engine rebuild shop (with plenty of landrovers in the yard), they tested head and measured slight warping and thus skimmed head. I did not get measurements from them, but i can follow up. Any thoughts?
jamesmartin
Well-Known Member
not specifically a head that needs 4 thou skimming has likely a longish life a head that needs 20 thou probably quite short,might be worth measuring valve stand down / depth of valve head from head face
Frankies Help
New Member
I still wouldn't rule out turbo oil seal damaged. 1-2mm lateral movement seems a lot to me. I just got a complete turbo core and replaced my old one. About £130.
Wicklaman
Member
hi James.
original coolant sensor indicated about 1/3 way which concerned me post work above. i have filled slowly per procedure and by volume input of coolant it is correct. swapped sensor for one from spare engine which started rising before thermostat housing was warm, got to half way few kms from house and after 6kms it rocketed to hot. i pulled in and checked hoses etc, new stat is working well (i tested it before install with water and temp gauge). checked rad and it is cool even though bottom hose is hot and top hose is hot. is it possible rad is able to short circuit? i thought the spare sensor was faulty until i checked rad.
jamesmartin
Well-Known Member
rad needs changing it was a common cause of over heating
Wicklaman
Member
i am a little puzzled why it did not overheat before i did the gasket and head. what happens to rad? blockages?
jamesmartin
Well-Known Member
300 rad fills and empties on the same side if core blocks or baffles fail water goes in straight down and out with out circulating through the rad
Wicklaman
Member
seems to add up. bottom and top hoses are hot and water moves in reservoir when i squeeze the hoses. to close the loop on this one, can the temp sensors fail such that they don't read high (1/3 from cold when engine is hot).
Original problem i set out to fix seems to be cured (no smoke/steam from exhaust) but this looks to be a deeper problem all round. once you start pulling the thread.
thanks for your help James
Wicklaman
Member
ok, some self education since i was stranded on the road the other night with "overheating" issue. the spare coolant sensor was 'green' type rather than the 'black' type which basically caused all sorts of inaccurate readings.
i swapped it back for original 'black' one and ran engine up from cold in shed yesterday while monitoring warm up with the temperature probe on my fluke multimeter. the thermostat opens when expected, temperature at external of the black sensor never got above 72degC. and the RHS of rad gets hot..approx 30-60 (bottom to top) LHS gets warm after loaded drive (30degC), the entire rad never gets warm however the engine temp is always stable. dash temp gauge sits between 1/3 and 1/2 way. it seems the engine is not running hot, checked along several placed of head and block while out for a drive. water in reservoir sits at approx 60degC. Seems like i was crying wolf with the green sensor. Thanks again to James for your help the other night...
I might upgrade to a digital gauge so i can see exact temperature, would be more reassuring to have a coolant level sensor also. anybody done this?
i swapped it back for original 'black' one and ran engine up from cold in shed yesterday while monitoring warm up with the temperature probe on my fluke multimeter. the thermostat opens when expected, temperature at external of the black sensor never got above 72degC. and the RHS of rad gets hot..approx 30-60 (bottom to top) LHS gets warm after loaded drive (30degC), the entire rad never gets warm however the engine temp is always stable. dash temp gauge sits between 1/3 and 1/2 way. it seems the engine is not running hot, checked along several placed of head and block while out for a drive. water in reservoir sits at approx 60degC. Seems like i was crying wolf with the green sensor. Thanks again to James for your help the other night...
I might upgrade to a digital gauge so i can see exact temperature, would be more reassuring to have a coolant level sensor also. anybody done this?
Wicklaman
Member
great, thanks. will have a look. assume its on the rad rather than on thermostat housing.
