P38A Head gasket advice needed

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the key to bleeding is leaving the cap off until the temp gets to about 90c, which means the thermostat is open and you've got circulation. switch off, let it cool for an hour, then put the cap on. go for a short drive (end of the road and back) in a low gear to keep revs over 2000 rpm, stop when it gets to 90-95 and let it cool down. take the cap off and fill to the mark.
if its even a bit below the mark, it will run hotter than it should
 
Thanks guys!

I did follow RAVE procedure including blowing out the bleed line from rad to expansion tank, however RAVE procedure is limited to basically 'fill it up, run it and continue filling it up'. Which I found strange anyway. Will try the tricks you have mentioned this weekend! Maybe I will also disconnect the return from the heater matrix to bleed that part, something my other cars all need to avoid air locks.

Many thanks!
 
I ran the engine with the car on ramps and the expansion tank cap off. Three times until hot then cooling down for 30mins. Managed to get another 2 litres in. Next I'll check if pipes to throttle bottle are clear, didn't have time for that.
 
pwood999 said:
Last time I did mine, I used a vacuum pump on the bleed hose. Sucks coolant into the engine & all pipes nicely.
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That sounds like a great idea! Gonna have a think how I can do something similar (don't have a vacuum pump).
 
Pressure helps. Apply pressure to the expansion tank then let it off quickly, helps the blighters escape. Doesn't have to be much, a couple of psi is enough to get a movement
 
I heard from a LR specialist that one of the illnesses of the V8 is that the cylinder liners start floating which will lead to coolant consumption and blowby 8bto the cooling system. When he hear the mileage on this car (260k kilometers) he said "let's hope it's not the original engine". Encouraging words.. but something I will keep in mind as it may be related to the issues I was having. Just thought I'd share.
 
They can if slip of they're not looked after but the failure seemed to occur around 60-80000 miles. If you're past that then likely ok.
The coolant issue is separate, caused by a crack in the block, which can also cause liners to slip
 
Liner slip is down to poor casting and the water jackets inbetween the cylinders are offset and the thinner wall of the jacket cracks and allows the aluminium block to shrink away from the liner, it's minute but enough to cause the liner to slap up and down, if left unattended it can bareak down in to the crank and split the block in two..

Not as common as you'd think, overheating to the point of pre ignition and running them lean are two of the most common causes, and obviously some bad blocks from the factory..

The Thor is more common for it due to the high running temperature to get the car through Euro 3 standards, keeping the cooling system in A1 condition is the most important thing for that engine.
 
Ratae said:
I can't remember the brand but one of the things that people put into the coolant system to block up leaks has exactly what you describes as 'glitter/sparkles' in it.
I think it's to help it block up any holes.
Some just put it in as a 'just in case' even if they don't have coolant loss.
Not a fan of any of them as I doubt they're going to do much to keep the smaller passages in the cooling system unblocked - but I do accept they might be the only alternative as a 'get you home' bodge.

I would suggest getting the car up & running & in normal use & keep an eye on your coolant levels.
A pressure test would be a good idea to see if the pressure drops without any apparent leaks - did this on my Classic using one of the Mityvac type devices ( does vacuum & pressure) & it showed up a slight weep from a hose joint which was solved by nipping up the hoseclip.
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I had a small gasket leak and used Prestone leak seal, has been as sound as a pound so far with no more coolant loss. I will eventually get the gaskets done but if the Prestone keeps working I will keep on trucking :)
 
ar1g3 said:
So this concerns my green 1999 p38 with 4l V8. It has been sat for 8 years before I acquired it.

I just did some major service work and found a considerable amount of milk in de oil filler cap. Also tiny tiny bit in the drained oil. After changing oil and running the engine visible condensation droplets in oil filler cap. Coolant level is low (only just in the expansion tank), but the drain plug was leaking a bit. No signs of oil in the coolant (eg. milk, black line in reservoir, black traces in coolant).

At first it seems to me that I have a coolant-oil gallery head gasket leak. However I find it strange that the contamination is only in one direction (coolant towards oil).

I don't know how what the heads look like on this engine. Is it possible to have an oil-coolant gallery leak on these or are they not adjacent?

Any other places where coolant could leak into the oil.?

On this type of leak I would expect to at least see some evident in the coolant expansion tank. From a sitting vehicle I expect some condensation in the engine but the amount of milk under the filler cap seems to be too much to be condensation related

I don't really care to do the work, and the parts don't seem too expensive at first glance, but of course if it doesn't need to be done it doesn't need to be done.

Any advice will be appreciated! Also ways to test the gaskets (except for compression test which i will do tomorrow)?
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This is one of Otto's freshly skimmed heads. Coolant passages are the slightly curved slots at the ends, oil passes up the stud / bolt holes to the rocker gear IIRC, there isn't a lot of oil goes up there. Most common issue is coolant oassage failure through to an end cylinder. Otto instead had blown through between 2 cylinders, although was also managing to seep exhaust into the coolant.
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The head bolts - or the stud washers & nuts if you've fitted a stud kit - effectively seal against the head so oil can't pass up or down them.

There are oil passageways from the block up through the heads & rocker shaft pedestal into the rocker shafts which are hollow.
Then out of the rocker shafts into the passages inside the rockers.
Some will also lube the rockers on the rocker shaft.
Through the rockers & onto the top of the pushrods before running back down.

Surprising how much cr8p builds up inside the shafts & I suggest you strip them & flush them out.

Get a suitable piece of dowel & as you remove & clean each item from the shaft put it onto the dowel. This will ensure it all goes back together in the same place & the same way it came off.

The passageways in the rockers can get blocked with cr8p & whilst you've got them off give them a good blast through with an aerosol of brake cleaner or other solvent. You may find some are so blocked - couple of mine were - you'll need to poke it out before blasting.

The Rover V8 is low pressure but huge volume.

The factory manual has a diagram showing the oil routing (right hand side left out for clarity). If you don't have the factory manual then this will show the relevant section. Probably best to ignore all the 'Click on this' and 'Download' nonsense as I've no idea what you'll end up with!
www.usermanuals.tech/d/land-rover-4-0-4-6-v8-engine-overhaul-4th-edition-rover-manual/part3#22
 
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So I thought this one was closed but alas it isn't. Tonight a mechanic friend came to pick up the car for its Belgian equivalent of the MOT, which is required to pass before you can register a car. 10mins driving and the temperature was in the red. Still a lot of air in the system it seems. Going to be a long weekend purging everything out...
 
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