Cylinder Head What would you do?

Not having a great day
I've been trying to do some compression testing following a brief diesel runaway. But, the compression tester I bought midweek is not working. Joint not tightened enough before threadlock has set and I can't shift it to tighten it up. I've messaged the seller on ebay, so they may send me another. My question is, is it worth waiting to try and get a pressure test on each cylinder? It would be good to know the results I reckon.
I've taken the heater plugs out and No4 is burnt away on the end Is this common?

If it's done that slowly over a long time I' hope the cylinder would be ok. If not I'm guessing it could be in a poor state. Good reason for compression test?
On the other hand I'm haunted by the possibility that the run away may have been down to the head gasket going between a cylinder and a push rod hole, so pressurising the oil and pushing it through the breather in to the air intake and/or taking oil into to a cylinder and burning it. So, I'm probably not going to settle unless the head gasket is changed.
It's time to pack up for the night, sit down with some Guinness and watch the Toon play Huddersfield.
Should I just start taking the head off tomorrow or wait and get a set of compression test results first?
What would you do?
Cheers.

Thought I'd take a close up of that heater plug end.

No3 is looking a bit oily too

A lot of runaways have been caused by the turbo seals letting oil through, it'd definitely be worth at least checking the turbo hoses, and taking the turbo unit off .. 'specially as you need to at least undo the manifold anyway ..

Cheap boroscope from ebay down the glow plug hole?

Paul D said:

A lot of runaways have been caused by the turbo seals letting oil through, it'd definitely be worth at least checking the turbo hoses, and taking the turbo unit off .. 'specially as you need to at least undo the manifold anyway ..

Click to expand...

Already done that, Paul. New (recon) turbo is already here and ready to go on. There was movement on the turbo, but not too bad. It's done 180k so thought it worth replacing.for peace of mind. One run away is enough! Cheers.

lynall said:

Cheap boroscope from ebay down the glow plug hole?

Click to expand...

I've got one of those! You know what, I've spend so much time and focus on that damn compression tester that I forgot about having it.
I'll have a look in tomorrow. Thanks for jogging the 'old' memory!

Looks like No.4 has got quite hot....

I'd pull the head just for peace of mind...

• You have experienced a 'run-away' event
• No. 4 Plug looks like it got hot and melted
• Common HG failure is between No.4 and the No.8 pushrod hole meaning it can ingest its own oil
• You found oil in the Turbo housing
• You have a fine mist of oil covering the bulkhead

To me, that all adds up to pulling the head to take a good ol'goosey gander in the bowels of the engine....head off and back on can be done in a day quite easily.

Saint.V8 said:

Looks like No.4 has got quite hot....

I'd pull the head just for peace of mind...

• You have experienced a 'run-away' event
• No. 4 Plug looks like it got hot and melted
• Common HG failure is between No.4 and the No.8 pushrod hole meaning it can ingest its own oil
• You found oil in the Turbo housing
• You have a fine mist of oil covering the bulkhead

To me, that all adds up to pulling the head to take a good ol'goosey gander in the bowels of the engine....head off and back on can be done in a day quite easily.

Click to expand...

As you know, your absolutely right. It's inexperience that's making me over think this. I've been thinking that a compression test would be of value. But, it probably won't help me a lot. Even if I do get a low reading it could be rings, valve guides or gasket. Thanks for the advice (again) and great summary of symptoms.

Gutted for you Al but whatever a compression test tells you, you wont rest or trust it until you change the HG.

mick the builder said:

Gutted for you Al but whatever a compression test tells you, you wont rest or trust it until you change the HG.

Click to expand...

You're absolutely right, Mick. Couldn't drive it with any confidence. Just been fixed on a compression test - stupid!

Right gents, I need those who know to tell me what these symptoms mean please.
Here are my injectors. Injector number 4 is grey and must have been getting hot. As per the heater plug above.

Here is a close up of it.

The others are similar except No3 looks oily
Here's the head. Number 4 cylinder has been hot I presume. The surface of the valves feel rough and look like they have been sand blasted.
Number 3 looks oily.
Number 1 looks drier than 2 and 3

This is a close up of No4

I can't see any problems with the head gasket No cracks or splits anywhere.

Top of No4 piston is dry and a bit rough. Not as bad as the valve faces.

I can clearly see honing marks on No2 and No3

The sunlight was making it hard to see, but couldn't see any obvious honing marks on No 1 or No4. I'll look again when the light has changed.
I could feel a light scratch on No 4 You can see where I have rubbed my finger down it.

What could be causing the problem in No4 ?
A few weeks before the runaway it started getting a bit 'lumpy' on start up in the morning. It was making a bit of light smoke out the exhaust and I put a post on LZ. It was thought a fuelling problem, so could this be the No4 issue?

Time to pull the motor out Al ! Don't think your going to fix it while its in !
I think i have just sent you some picys from my phone ?? of wot append to mine

Steve

Thats got so hot its melted the piston and transferred the alloy to the valves and injector!

Magicgrotto said:

Time to pull the motor out Al ! Don't think your going to fix it while its in !
I think i have just sent you some picys from my phone ?? of wot append to mine

Steve

Click to expand...

Cheers, Steve. By, yours were in a hell of a state!

lynall said:

Thats got so hot its melted the piston and transferred the alloy to the valves and injector!

Click to expand...

Ah, so where the valve face looks shot blast it's actually piston alloy droplets stuck to it.

Did the injector go faulty first and cause the over heat in that cylinder? I'd like to find out the cause and possible sequence of events.

I suspect the injector, worth getting them tested.

zeaphod said:

I suspect the injector, worth getting them tested.

Click to expand...

I can only see one on the tiny holes in injector No4. It looks like they are all blocked by the alloy, if that's what it is. So probably beyond testing. You can get them refurbished though, can't you?

definetely dont refit no4 injector

jamesmartin said:

definetely dont refit no4 injector

Click to expand...

Cheers, James.
What do you think caused it to overheat?

that injector id think is the source of your issues

A faulty injector can make the cylinder run lean - and consequently hot. No4 is beyond help, but the others may be fine.

jamesmartin said:

that injector id think is the source of your issues

Click to expand...

zeaphod said:

A faulty injector can make the cylinder run lean - and consequently hot. No4 is beyond help, but the others may be fine.

Click to expand...

Is that bad luck, or my fault due to not having them checked at a certain number of miles?