2.5NA coolant boiling

Was driving my 1985 2.5 NA diesel back home last night and noticed the temp gauge was showing hotter than usual. I seemed to be having poorer performance up the hills, having to change down earlier than expected.

Parked up and there was a bubbling noise and the smell of coolant so lifted the bonnet. The coolant was bubbling out of the overflow. Top of the radiator was hot but bottom was stone cold.

This morning I looked in the coolant and it seemed pretty empty. Added 6 litres which didn't make a dent. Started her up and immediately, coolant was spraying out of the overflow.

Any advice as to what could be going on?

The thermostat was checked a month ago and seemed to open fine. The coolant was drained and refilled at the same time too.

I suspect its the head gasket

Rocky09 said:

Started her up and immediately, coolant was spraying out of the overflow.

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I suspect its the head gasket too

Was going to say knackered water pump but if it does it straight from cold then its defo the head gasket.

Thanks both

Yeh took it to a landy mechanic and it's def the head gasket. He said 'Just go on t'internet, print off a guide and take a day over it'. I'm not so sure. Is it really as straight forward as he says? All the manuals make it look like just a nut and bolts job, I just reckon the risk of messing something up is pretty high!

Its not a bad job on the NA, usually takes a bit of patience getting the head free from the block but its not a hard job.
Just be careful to make sure all the rocker gear stays together when you lift it off, you can fix it to the rocker cover to keep it all in order.
Make sure you clean all traces of the old gasket off taking care not to get crap dropping down the push rod holes.
Take a look at my 110 thread as you will see mine stripped out to give you an idea.

Have a go, its one of those jobs that seems to inspire seft confidence. if it works out ok then you will never look back, if it doesent, well wtf ! Plenty of lads on here will be delighted to help (from a distance) , just give us some pics as payment.

Did mine at the side of the road on my TD (which is slightly harder due to the turbo being in the way!) in a day. All you need is a torque wrench, a few sockets and a new gasket - along with some water and oil! I think i used and old chisel to tap the head off the block being careful not to damage the surface.

A bit of emery paper is also needed to polish the surfaces up prior to putting it all back together

You may also want to have a look at the valves and seats +/- get them referb'd prior to putting the head back on - also check the inserts for the pre-ignition/heater chambers as mine had cracked up slightly - not sure if it made any difference by replacing them but I guess it prevented early failure - also put in new injectors at the same time - that worked a treat on the lack of power especially as one was leaking fuel all the time even at low pressure! - Saved on a load of fuel as well!

See this guide -
2.5 N/A head gasket replacement - Land Rover Technical Archive - LR4x4 - The Land Rover Forum . It's from another forum, but I have to post it as it's the best guide I've found. I followed it - it was the first major mechanical work I've done, and it would have worked out fine for me if my head had not been cracked.

Be aware, that as well as replacing the headgasket, you need to determine what caused the failure - water pump for example.

Check the head carefully for cracks and watch your back when lifting it clear - if possible, get another pair of hands to help - it's bloody heavy!

you need to look closely between the valves on a 2.5 head they are very prone to cracking

jamesmartin said:

you need to look closely between the valves on a 2.5 head they are very prone to cracking

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Like this one on mine:

yes thats buggered ,also in the scallop often difficult to see

Sods law this - my heads cracked in three places :'(

How prone are they to cracking? Is it something I've done or just an 'its a 30 year old head thing'. Feeling a bit gutted that I might have knackered her

"I might have knackered her"

No actually your halfway there to fixing it !