4.2 Diesel GRX

[Michael]

Th black top vs silver top discussion is a nitemare, its impossable to guarantee if an engine is a real silvertop or not as both had a vacum pump on the alternator as well as the one on the timing cover at one stage if I remember correctly. Its as simple as changing the valve cover or timing cover to create a "silver top".
I have spent hours on the Ausie forums regarding this and even they have trouble determaning this. I honestly dont think the real silvertop engine reached our shores unless it has been imported.....I can also be wrong here.

[Alex Roux]

Since it is a conversion, more questions.
Quality of the conversion will determine wether it is a bargain or a lemon.

[SJC]

Would definitely get Graham to have a look at this one before I would think of buying it.......

Defnitief.

Die verkoper se dat die engine oor gedoen is (seker vervang?), so 12000km terug.
Vin no: JN1TBSY61Z0503024 .

[ricster]

That is also very true. I believe that we here in SA are very lucky... I say this due to the fact that both Michael and I ( and Chuck, if I'm not mistaken ) are all black top TD42's, yet when the motor was opened up there are oil squirters under the pistons which I am lead to believe the black tops aren't supposed to have.

Mine in particular also has the bigger gudgeon pins ( 30mm and not 28mm ). So I think Nissan built up a few GU Patrols from the scraps that were left in Japan before launching the ZD30 Patrols. Much to our advantage in hindsight !!!!

[ricster]

JN1TBSY61Z0503024 Nissan Patrol / Safari 2005 VIN: JN1TBSY61Z0503024

WMI / VDS / VIS: JN1 TBSY61 Z0503024
Manufacturer: Nissan Infiniti Motor Japan

Brand: Nissan

Model: Patrol / Safari

Check: 1

Year: 2005

Sequential number: 03024

Approx. mileage: 162,606 km

[Clem]

So according to the VIN number the car is a 2005 model. Clearly the engine is not the original engine but an earlier engine that has been put into the car; no one knows what the mileage on that engine actually is and whether the internals are blacktop or silver top. Also, unless you know these things well, you do not know how well the conversion has been done (how difficult would such a conversion be, anyway?). I have been watching this thread with some interest but am uncertain as to what the car is actually worth and what issues there could potentially be with something like this. The mileage is fairly high but probably not excessively so. Seeing as I have been toying with the idea of a second Patrol for some time now. But I am totally uncertain as to what to make of this particular fish… or fowl…or...

[Michael]

This is quoted off the Aussie forum, and even here it seems like I have got a Silver Top combined with a GU black top..... something. Mine also has the 30mm pins and oil squirters

GU turbo black top, has the turbo oil drain cast into the block. 28mm gudgeons, different bolt pattern on the back of the crank. Vacuum pump driving off timing gear below fuel pump.
Good for 900+ Nm if you build them properly,precombustion chamber ports are larger.

Compression ratio 22.5:1
Engine number starts with TD42nnnnnT

Silver top (which dont all have silver rocker covers) Build date to somewhere around August 1995. Vacuum pump on back of alternator. Good for 650-700 Nm at 30 psi in short bursts if you watch your gauges with standard internals. 30mm gudgeons. "small/standard" back end on crankshaft. small precombustion chamber ports. Compression ratio 22.7:1. I've just blown one of these up being an idiot and the block and liners have disintegrated between #3 and #4. I'd keep it to under 650Nm with these. Engine number starts with TD42nnnnn

Good for mild boost only:
non turbo GQ and GU "black tops" built post august 1995 approx. Vac pump driven off timing gear below fuel pump. No turbo drain cast into block, "small/standard" back end on crankshaft. 28mm gudgeons.
12 psi non intercooled, 15psi intercooled, Thou Shalt Not Pass this boost level. reasonably lively engine due to the lower mass pistons, especially if you use 4.375 diffs. small precomb chamber ports. compression ratio 22.7:1
the pick of the bunch for moderate applications because everyone wants the "strong" ones and the lower reciprocating mass helps performance

[ricster]

hahaha.... yeah... the first one is the turbo GU they used in the 4.2 turbo pickup.

Like I said we have a mishmash here for some reason.... But I'm not complaining !!!!

[Peter Connan]

Also, unless you know these things well, you do not know how well the conversion has been done (how difficult would such a conversion be, anyway

By now you know that I am generally allergic to conversions.

However, since this is a normally-aspirated 4.2 diesel engine, I doubt the conversion could cause any problems, except perhaps minor ones like water pipes or exhaust routings. I say this because:
1) The engine requires no electrics or electronics to actually run, just to start.
2) The manual gearboxes on all the Patrols are basically the same, thus it is a straight bolt-in. Even the engine mount positions are probably correct.
3) The radiator capacity is approximately the same for any of the engines the car may have come out with.

Thus for once, I am not concerned about the quality of the conversion.

What does bother me is the work done on the engine itself, what the real mileage is and why whoever did it felt the need to turn the odo back.

I would think an oil analysis and G-Tech health check should answer most of the questions though.

[ricster]

A silly question, but can the digital odometer be "turned back"? I assume on the GQ "turning back" the odo is achievable, albeit illegal if I'm not mistaken.