Got to fix this first! Even if the engine goes for sale.

Still considering the turbo, not sure how to control it yet.
 
So before ripping the head off, will be air pressure testing from the coolant bottle and listening in the spark plug holes!
If this proves the case then will remove the head and post photos.
Trying to decide whether to reseal liners while doing it or just leave them alone.
Probs depends what I find, will, of course, be asking advice before proceeding!
 
Put the pressure tester on the coolant bottle. Pumped to 20psi. Could hear a hiss! Both return hose joints to the coolant bottle were hissing. Took off the crimp clamps and fitted jubilee clips. All good but pressure still dropping very very slowly. That was probably the cause of the boiling coolant in the first place.

Took out plugs, no hiss. Took off oil filler and dipstick, no hiss.

Started engine, and here is the interesting bit, pressure still dropped slowly.
No sign of water in cylinders. Compression good at 200, 220 psi (on my enthusiastic gauge!)

Have left pressure on overnight, it stabilises at around 15 psi then the drop is tiny.

I figured engine running would either stop the fall in pressure or ramp up the pressure in the bottle, unless the tester has a non return valve.

Bit confused by that. Not an obvious head problem but how to find out where the air is going? No water in oil but slight light brown deposit in oil cap.

Is it worth tightening the head bolts?
Is it worth trying to pressurise the oil system and see if it comes the other way?
 
I figured engine running would either stop the fall in pressure or ramp up the pressure in the bottle, unless the tester has a non return valve.

If you've pressurised the coolant to a set amount, then started the engine. I'd expect to see the pressure rise while the engine was running, if the HG was allowing combustion gasses to enter the cooling system.
If there no rapid pressure rise when cold, it would point away from the HG IMO.
 
Agree. Wonder if the tester has a non return valve on it?
I left 20psi in last night and it is zero this morning.
No more sounds of air or water leaking.
No noise in bores when listening in plug holes.
No rise in oil level.
Compression good and consistent.
This one is beating me!!
Happy to do the head gasket, but not if it isn't needed!!
 
Agree. Wonder if the tester has a non return valve on it?
I left 20psi in last night and it is zero this morning.
No more sounds of air or water leaking.

Pump it to 20 PSI (I'm guessing there's coolant in it?)
Leave over night, lock into the cylinders next morning, to see if any have coolant in them.
If not, then it's almost definite that the coolant is going somewhere else, maybe a weeping pipe connection somewhere, or the heater matrix is leaking?
 
Thanks, can (or more relevantly does), the K series fail with oil and water ways joined but not combustion chamber??

Not ruled this out yet, have had pressure on it overnight so will take a look in cylinders again. I have a flexi camera that I could use.
I guess if I keep applying pressure it will reveal itself somewhere!!
 
Worth also checking the expansion tank itself, mine spit around the seam only slightly but it was enough to leak off pressure..

very similar to you funnily enough!
 
Thanks guys.
So, pressurised, left it, pressurised left it, checked bores, no sign of dampness. Plugs all the same colour.

So pulled it out into the open air, pumped it up to 20psi and got my trusty hand sprayer with a bit of washing up liquid in.
Sprayed everywhere, hoses, joints, manifold!! Header tank, return pipes etc.

Guess what, only the brand new pressure tester pump to cap fitting blowing tiny bubbles!!

Fitted an o ring to make it fit properly and bingo. No pressure loss.

So, were the 2 x small leaks that I found yesterday enough to generate the behaviour that I saw? Boiling coolant, loss and hard top hose??
Maybe.....

So now have got engine hot and tested again, no pressure loss. Put blue dye in bubble fitted to header, no colour change.
Checked oil no sign of water. Checked compression and all good.
Can't think of anything else to check.

Looks like we are good to go again!!
What would others do? I think with an engine that runs so close to boiling, I have learnt that even a pin hole can push it over.
Might just have got away with it (for now).
Car back in use and being closely watched for now.

Thanks for all the input, might help others but 'don't rush in and strip engine apart' is the lesson to all I think! :rolleyes:
 
Who thinks this might be solved - 2 tiny leaks.
Are HG being replaced unnecessarily - I nearly went there too.!?!?!
Give a dog a bad name.....
There have been many many cases where a K series HG was replaced unnecessarily when the real cause was a leaky hose or water pump. And probably many cars written off as unrepairable when the fault invariably returns.
 
So a thread update.
No it didn't run rough at all. Drove perfectly and I thought having found the 2 minor leaks that all was well.
Have used the vehicle on short runs for a couple of weeks and all good. No water loss.
Wife went out to use it on Friday, heard it crank and sound like it locked mid crank.
Then it fired with a cloud of steam out the exhaust.
Immediately took it around to the workshop, applied pressure tester to coolant and removed plugs. Cylinder 4 was wet!!
Cranking with plugs out shot a jet of water into the air. So fault has finally revealed itself. Thought I'd got away with it but must have been some slight damage which came to the fore eventually.
It's in the line up for a replacement gasket now after all. :(
 
Last edited:
So a thread update.
No it didn't run rough at all. Drove perfectly and I thought having found the 2 minor leaks that all was well.
Have used the vehicle on short runs for a couple of weeks and all good. No water loss.
Wife went out to use it on Friday, heard it crank and sound like it locked mid crank.
Then it fired with a cloud of steam out the exhaust.
Immediately took it around to the workshop, applied pressure tester to coolant and removed plugs. Cylinder 4 was wet!!
Cranking with plugs out shot a jet of water into the air. So fault has finally revealed itself. Thought I'd got away with it but must have been some slight damage which came to the fore eventually.
It's in the line up for a replacement gasket now after all. :(
Sorry to hear that buddy :-(

That looks fun, have you got one? You can get some 5.5mm and some 7mm winner if there's a difference to the image?
I've got one, 7mm IIRC, image quality is very much "early webcam" rather than blockbuster 4k UHD, but it's ok as it's on yor phone's small screen, and infinitely better than not seeing anything. If you get oil onto the lens they are a bugger to clean, but even if you can't get it clean again, it's such a cheap bit of kit it's almost disposable, as in it costs less than abox of beer, so not a big hit to write it off.
 

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