Blown ZD30 more info

[Burto]

HI all,
Thought I would add what happened, in case it may provide someone else with some info for the future.

Vehicle is a GU III built Dec 2002, manual with the famous ZD30 engine, it has 301700 kms, hence my belief that I had dodged the bullet.

Engine mods are
Gauges EGT, Boost, Oil pressure, water temp all fitted
Provent fitted
Engine oil and filter changed every 5000.
Had a new injection pump fitted approx 4000kms ago
MAF sensor regularly cleaned, engine blew on Thursday, MAF cleaned on Monday before trip

At the time of failing to proceed, had been towing camper trailer in some hilly country, had used 3rd/4th and on one hill back to second to reduce load on vehicle, noticed blue smoke in rear, thought a tyre at first, when stopped lots of blue smoke, provent was pressurised, engine running with miss. NO mechanical noises or rattles.

Regards
Burto

EGT had been to 450 then cooling down to 250 on downhills as normal, oil pressure normal, coolant temp normal, boost normal bouncing around the 14 psi.

Vehicle towed home, now in shed ready for rebuild. This engine passed away very quietly without much fuss, so mileage has nothing to with it, regular servicing makes no difference, in my case the gauges showed nothing out of the ordinary, it is a gamble you pays your money and takes your chances.

[rusty_nail]

sounds very similar to my circumstances mate, i blew my motor last july, and have now got it back on the road albeit with some other problems lol. i ended up rebuilding my motor again, what are you thinking of doing?

[Burto]

Thanks Rusty for your response, will probably strip it down to head off to assess any damage, then drop the sump and do a in chassis overhaul, if there is no significant damage or wear. Will get head done in town, and the injectors serviced. Failing that block out and rebore to +0.05.
The only thing I cant believe is that to remove the upper sump, the gearbox needs to come out, I am still trying to get my head around that one.
Being retired gives me the time and being a vehicle mechanic, aircraft engine fitter and a automotive engineer gives me the confidence to tackle it.
Will post any updates as the strip down progresses.
Regards
Burto

[rusty_nail]

Thanks Rusty for your response, will probably strip it down to head off to assess any damage, then drop the sump and do a in chassis overhaul, if there is no significant damage or wear. Will get head done in town, and the injectors serviced. Failing that block out and rebore to +0.05.
The only thing I cant believe is that to remove the upper sump, the gearbox needs to come out, I am still trying to get my head around that one.
Being retired gives me the time and being a vehicle mechanic, aircraft engine fitter and a automotive engineer gives me the confidence to tackle it.
Will post any updates as the strip down progresses.
Regards
Burto
Haha well sounds like u have the vehicle xp to get the job done. I'll pm u a PIC of the receipt if you like to see what sort of costs your up for.

[Burto]

Well have started the strip and inspection, looks like may have dodged a bullet.
All intake hoses, intercooler and swirl valve have liquid engine oil in them, not burnt oil but good ordinary engine oil, in fact a small quantity of oil ran out of the intercooler when inverted. Hmm Turbo ??
Turbo off, impellar elbow again contained liquid oil with evidence around the actual impellar the turbine also has oil sludge in exit of the "snail" and around the turbine.
When the turbo shaft is grasped at either end it can be rocked slightly not much but enough that it can be felt.
Removed the rocker cover all looks normal, normal engine oil with no signs of crankcase fuming.
Removed the glow plugs, turned engine over by hand all cylinders were "huffing and puffing", put each cylinder in turn on compression stroke and locked engine, introduced compressed air pressure in through glow plug hole and checked for excessive leakage at crankcase (rocker cover off), exhaust manifold and intake manifold, all cylinders held pressure.

So now thinking, turbo seals failed, resulting in oil at engine pressure being sprayed into intake, resulting in the excessive oil burning and rough running, engine still started normally but ran rough and blew heaps of smoke.

Now to look at overhaul the turbo, replacing the seals and brgs or fit new turbo. On trucks always overhauled the turbo providing that the snails were not burnt out; hard to justify the cost of a new turbo ($5000 +) to a truckie when kits were available.

Didn't know much about this motor, but learning fast. Love the retained washers on the injector spill pipe.

Will post more as the adventure continues

Burto

[Covo71]

Hi Burto, I saw genuine Nissan patrol turbos on an email from Denco diesel just a couple of days ago for $1200. I can forward you the email if you PM your email address.

[Burto]

Thanks for the response have sent PM this morning, will certainly look at this option.

BUrto

[threedogs]

these motors dont like being overfilled with oil,
First I'd be fitting a catch can to "catch" all that oil.

[Burto]

Thanks Threedogs, provent is fitted, but little or no oil in it.

Provent was checked on the Monday when checked engine before the trip, and MAF cleaned.