Engine rebuild - after engine fail in Germay (Jul 2024)

[Jim San]

I'm not good at build threads and i'm far from being a mechanic so if thats why you are here, best lower your expectations from this point on 

The Situation:
The holiday was great and daily temps were hot hot hot.
In short, temp guage had been sitting low for best part of a week - no issue with water levels.
 - Day before breakdown, we'dcovered no more than 200k, at the site I was concerned at how hot the engine felt - i left the tailgate up and bonnet off to cool.  the water in the header tank was sitting high and remained so when it had cooeld(I dont have the 2 tank system).
 - Day of breakdown, we travelled around 50k stopped at a campsite gate, enquiry took longer than thought so I shut the engine off.
5 mins later, tried to start it and - absolutely nothing - just lights on the dash - not a flicker.
Tried the camp site jumper pack just in case but still nothing
Checked fuses - NFF
Couple of hours later, recovery truck arrived.  Tried massive jumper pack and it burst into life - making a horrible intense metallic rattling noise (the sort of noise you know the sensible thing to do is shut it off).
No issue with water, or the oil.   Got it repatriated from Rothenburg (there is a great VW service centre there, bloke is supper helpful).

Back in the UK, over a long drawn put period, I picked away at it trying to find the fault.
Pressure check showed Cyl 2 was low in comparision 
Coolant was clear
Oil was clean - not metal etc.
Endoscope in sump and down glowplug holes showed nothing.

Head is off - headtechnique in Telford have tested aand confirmed its ok, all it needs is a freshen up and valves seating again (relief)
Injectors - united diesel nr Telford have tested, Electrically sound but diesel is more a dribble than a mist (they are being refurbed)
Pistons - fairly black around the top 1/3, just look worn, not damaged - but i'm not the best person to judge this
Bttom bearing - as above - just look worn, no damage.

So, i'm still non the wiser, 

Some months prior to trip, had fuel pump refurbed as it was leaking


I am adding the cost of things as I go along. You could easily find cheaper, but i buy best quality based on advice from the experts im using to do the work, but free to comment:

Costs: so far = £625 state: in bits!

Injectors 4x 1.9 - test, refurbished with Italian tips (bosch out of stock everywhere) £315

Head gasket & bolts est £120

Head test and overhaul £190

On the to do list:

Honing barrels:

Rings and she'll bearings:

[colinthefox]

Some months prior to trip, had fuel pump refurbed as it was leaking

Well, funny you should say that.......

My Perkins 4.108 powered Commer PB van ran OK for 6 years after my engine rebuild, until I had the injection pump rebuilt by a "reputable company" as it was leaking. More smoke than before. Two months later the head gasket failed. Replaced head gasket. Failed again. Head skimmed. Failed again this May. I learned how to check fuel delivery of the pump. Fuel delivery had been set way too high by "reputable company", resulting in high combustion temperatures. I reduced fuelling to correct level. Smoke all gone. I still don't know if I have finally cured the head gasket problem, but hopeful now.

Your story seemed strangely familiar.

[silverbullet]

Now I'm no diesel expert but if the spray pattern was poor then either it was running rich (usually makes them run a bit cooler) or lean (hot)

You report that it seemed to be very hot, so I'd go with lean AND a suspect or misreading temp guage. Electrical investigation required.

[silverbullet]

Also, the failed restart suggests a near seize-up due to very hot pistons and cylinders.
Thats probably whybit sounded so dreadful when it did finally restart. I wouldn't trust the bottom end after that, the bores may not be scored but I would renew all the crank bearings at the very least. Easy job on an inline.

[Jim San]

Now I'm no diesel expert but if the spray pattern was poor then either it was running rich (usually makes them run a bit cooler) or lean (hot)

You report that it seemed to be very hot, so I'd go with lean AND a suspect or misreading temp guage. Electrical investigation required.

I'll get more info when I pick up the injectors as to how big or little the dribble was (they are now refurbed - not a cheap process)

Luckily the hot running didnt warp the head as that seems fine.  
Coincidence of temp guage playing up is sods law but quite likely.  

[Jim San]

Also, the failed restart suggests a near seize-up due to very hot pistons and cylinders.
Thats probably whybit sounded so dreadful when it did finally restart. I wouldn't trust the bottom end after that, the bores may not be scored but I would renew all the crank bearings at the very least. Easy job on an inline.

Temp seize is what we thought/worked out.  Ignition lights were bright, headlights were 'bright' so ruled out battery flat.
Plan is to hone the bores, replace the rings and bottom end and rebuild.   Plus a ton of little jobs in the engine bay whilst its empty
 

[colinthefox]

Now I'm no diesel expert but if the spray pattern was poor then either it was running rich (usually makes them run a bit cooler) or lean (hot)

You report that it seemed to be very hot, so I'd go with lean AND a suspect or misreading temp guage. Electrical investigation required.

That's the case with petrol engines. With diesels it's the other way round strangely. Overfuelling leads to higher combustion temperatures which can for example burn holes in pistons, or as in my case burn out the head gasket. There's no such thing as a conventional diesel running "lean".....as the air intake is unthrottled and only the fuel delivery is changed, there is always an excess of air, and especially "lean" at part throttle.

A poor spray pattern would create dieselly noise due to unruly burn patterns, and partially burnt fuel exploding at the wrong time. It could also wash the bores with unburnt fuel.
 

[Jim San]

Now I'm no diesel expert but if the spray pattern was poor then either it was running rich (usually makes them run a bit cooler) or lean (hot)

You report that it seemed to be very hot, so I'd go with lean AND a suspect or misreading temp guage. Electrical investigation required.

I'm trying to learn why all 4 injectors would go the same way at the same time.  (so far it: bad fuel, water, contamination, component not fitted correctly, electrical problem)

Fuel system had leaking issues but didnt effect the running - fuel pump leaked and so did the return lines on tickover - had fuel pump refurbed before the MOT (around March) and did the return lines literally before we got on the Tunnel.

 

[silverbullet]

Now I'm no diesel expert but if the spray pattern was poor then either it was running rich (usually makes them run a bit cooler) or lean (hot)

You report that it seemed to be very hot, so I'd go with lean AND a suspect or misreading temp guage. Electrical investigation required.

That's the case with petrol engines. With diesels it's the other way round strangely. Overfuelling leads to higher combustion temperatures which can for example burn holes in pistons, or as in my case burn out the head gasket. There's no such thing as a conventional diesel running "lean".....as the air intake is unthrottled and only the fuel delivery is changed, there is always an excess of air, and especially "lean" at part throttle.

A poor spray pattern would create dieselly noise due to unruly burn patterns, and partially burnt fuel exploding at the wrong time. It could also wash the bores with unburnt fuel.
 

You learn something new every day!

[Jim San]

[quote=colinthefox post_id=8344227

That's the case with petrol engines. With diesels it's the other way round strangely. Overfuelling leads to higher combustion temperatures which can for example burn holes in pistons, or as in my case burn out the head gasket. There's no such thing as a conventional diesel running "lean".....as the air intake is unthrottled and only the fuel delivery is changed, there is always an excess of air, and especially "lean" at part throttle.

A poor spray pattern would create dieselly noise due to unruly burn patterns, and partially burnt fuel exploding at the wrong time. It could also wash the bores with unburnt fuel.
 
[/quote]

I'm not sure what a dieselly sound is, but I was certain mine sounded different with the refurbed pump fitted - slightly more noisy/ bangy

Top end seems to have survived, head gasket mostly intact, minor signs of degredation (according to the head shop), not twisted, they have pressure tested and bathed it and its all good, they will give it some tlc and I'll have it back next week, complete with quality new head gasket nd bolts
Pistons not holed or melted. I'm thanking my lucky stars it's not totalled but wish fault was more obvious

[colinthefox]

I'm not sure what a dieselly sound is, but I was certain mine sounded different with the refurbed pump fitted - slightly more noisy/ bangy

Top end seems to have survived, head gasket mostly intact, minor signs of degredation (according to the head shop), not twisted, they have pressure tested and bathed it and its all good, they will give it some tlc and I'll have it back next week, complete with quality new head gasket nd bolts
Pistons not holed or melted. I'm thanking my lucky stars it's not totalled but wish fault was more obvious

By "dieselly sound" I was referring to exactly what you describe as in "slightly more noisy/bangy". I believe it's referred to as "diesel knock", not to be confused with the normal diesel noises.

The other thing that I found during my recent research, was that there are perils in mixing and matching components. Injectors have to be matched to pumps, and both matched to the engine. For example, the IP cam profile is matched to injector spray pattern, which is matched to the engine burn pattern etc., so I don't like to mess with any of that stuff. That's why I was mighty annoyed at finding that my IP had come back overfuelling.

So I'm wondering whether the fact that you have changed the IP to a Landrover unit has something to do with your troubles. Is it matched to the injectors?
 

[Jim San]

 

By "dieselly sound" I was referring to exactly what you describe as in "slightly more noisy/bangy". I believe it's referred to as "diesel knock", not to be confused with the normal diesel noises.


So I'm wondering whether the fact that you have changed the IP to a Landrover unit has something to do with your troubles. Is it matched to the injectors?

Landrover pump and injectors were on it when I bought it 10yrs ago - until recently they have had no issues and no attention.  It used to run reliably and well.

Re the diesel knock, I even started phoning around a few local places to see if they would adjust the setting on the pump but becuase its non standard, i didnt get anywhere.  Something else i'll need to overcome before running it proper (long way off that!)