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Re: My GU 4.2 Turbo Diesel

Posted: 14 Mar 2017 10:42
by Michael
Ok so an update on my Patrol.....have not done anything to it for a while.

With the Dune trip just around the corner and with loads of drag racing waiting I did not want to take a chance with my already very worn clutch and decided to change it over the weekend. I have already bought a new kit from Nissan a long time ago and it is now finally installed.

I bought the car with a pirate kit in and it was already worn back then. I have now done more than 40,000km after that so it is overdue.

So quite a big job if you don't have a lift and/or a gearbox jack. So I decided to rather take out the engine. Started at 8:00 AM and had the engine back on its mountings at 14:00 same day. Took another 4 hours or so to get the wiring and piping sorted.

Some interesting things that have happened since the clutch kit was changed.
1. The clutch is about two times as soft to push in (this was expected and is common with a new clutch)
2. I used to have this rattling noise coming from the gearbox when the car is in neutral and clutch not depressed which many TD42 owners have and was said to be the gearbox gears making that noise. It is not totally gone after the clutch replacement, so I will point this to the clutch plate instead.

I did not take many pictures as I was really rushing to get the job done, but took one just as I had the engine back in its position.

Re: My GU 4.2 Turbo Diesel

Posted: 14 Mar 2017 10:45
by iandvl
Respect Michael. :salute: :salute:

I guess you've had that motor out a few times before. I'd be too frightened of screwing stuff up to do a job like that on my own... :rolling: :rolling:

Re: My GU 4.2 Turbo Diesel

Posted: 14 Mar 2017 10:56
by Michael
I Think it gets easier after the 5th engine install :lol:

I see now I have never posted new pics of how my Patrol looks with the new rims and tyres I installed...... ish

So here are two nice ones Peter Conann took at Hennops the other day

Re: My GU 4.2 Turbo Diesel

Posted: 14 Mar 2017 18:07
by hugejp
So hoe lyk die workshop nou???

Ons het dalk werk om te begin...

Re: My GU 4.2 Turbo Diesel

Posted: 14 Mar 2017 19:39
by Michael
Ons sal praat as die duine trip verby is......ek het plek :thumbup:

Re: My GU 4.2 Turbo Diesel

Posted: 14 Mar 2017 21:20
by Wilkie
MMMMMmmmm..Michael dit lyk my ek en jy het die selfde werk gedoen oor die naweek...
ook 4.8 motor getrek ( met seer hart) en 4.5 ingesit en dit vir die Duine trip..
moet ook se dat my koppelaar is super sag na die nuwe een ge-installeer was.. :biggrin: :biggrin:

Re: My GU 4.2 Turbo Diesel

Posted: 24 Aug 2017 16:58
by Michael
Right so time to update my thread here as quite a bit has happened recently.

Things have gone south when i was traveling north for the annual river trip. Just when I reached Bela Bela I noticed a slight misfire and saw quite a bit of blow by when I opened the oil filler cap. I knew there were an internal failure and suspected a cracked piston. I turned back, took the head off and found the following.

No. 6 Piston had a massive crack in and this was the cause of the misfire obviously, but it made no sense as I built the engine only 50,000km ago and all temps were kept well within the safety margins. I took out the engine and stripped everything as I decided against just replacing the pistons and doing it properly.

Upon closer inspection and going back to the original purchase of my parts I found that the "turbo" pistons I was supplied with was actually NOT turbo pistons :surprised:
This was was very upsetting as anyone can imagine as this should never have happened.

Some pics of No. 6 Piston from a couple of angles. It actually almost cracked right through the middle and it could have ended easily with a conrod through the block if I continued driving like that.
piston5-2200.jpg (236.58 KiB) Viewed 644 times
piston4-2200.jpg (142.3 KiB) Viewed 644 times
piston3-2200.jpg (171.14 KiB) Viewed 644 times
piston2-2200.jpg (123.98 KiB) Viewed 644 times
piston1-2200.jpg (148.7 KiB) Viewed 644 times
Now below is a photo of the Non turbo pistons vs the turbo piston i am planning to install in my engine this time round.
This is the same spec piston found in the UD40 trucks and is the same pistons the Ausies use to build their 250kw 900Nm engines of madness so they should be able to handle my hopefully 130kw and 450Nm on the rear wheels I am after with ease.
piston comparison-2200.jpg
piston comparison-2200.jpg (198.76 KiB) Viewed 644 times

Re: My GU 4.2 Turbo Diesel

Posted: 24 Aug 2017 17:12
by Michael
Now I am not too sad about the whole episode, even if it was just a very expensive exercise to prove that you cannot run 1 bar+ boost on N/A pistons so that someone ellse makes the correct decisions when building an engine I guess it has a purpose. Its a blessing that ONLY the pistons were cracked and nothing ells was damaged
From the start I built my engine to do some testing and experiments as we are not even close to what the Ausies know about these engines, but there was only one way of doing it and thats try and implement what they have done and picking up their bread crumbs left of the forums.

So some new stuff planned for my new engine build:
1. Sending in my crank, front pully, nut, flywheel, pressure plate, clutch disc, conrods and pistons for some balancing :biggrin:
2. I also purchased some Nissan TD42T pre-combustion chambers and did some porting on them. (see pics below)
3. Planning on ceramic coating the piston crowns as well as the precomps inside and outside if my budget allows it.
4. New top mount turbo manifold
5. new 63mm polished mandrel bend boost pipes
6. stainless air box
7. will be running 1.2 bar boost hopefully if I can squeeze a bit more fuel out of the pump
8. new TD42T piston oil squirters to make sure as much possible oil reach the piston crown. (see below pics)
oil squirters-2200.jpg
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precomps-2200.jpg (289.05 KiB) Viewed 641 times

Re: My GU 4.2 Turbo Diesel

Posted: 24 Aug 2017 17:17
by Anthony Forgey
It's amazing that the pistons lasted as long as they did with 1 bar boost. Just imagine the possibilities with the new (better) turbo pistons.

I hope your last few bits arrive soon so that the vehicle can return to its natural habitat

Re: My GU 4.2 Turbo Diesel

Posted: 24 Aug 2017 18:11
by iandvl
My vehicle's natural habitat is the gas station. Its secondary habitat is where it should be, and the third is tar.... It is petrol though, which means it is thirsty... :rolling:

On a serious note: wow, Michael. Not being a diesel 'kenner' I am a little clueless about turbos and boost and stuff. But the comparison photo of the pistons ? That is just incredible.... :|

Edit - PS: Hope all is sorted very soon.