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Re: My '98 GU 4.2 TD
Posted: 25 Oct 2017 08:11
by hugejp
Sad news indeed!
Good luck with the repair.
Re: My '98 GU 4.2 TD
Posted: 25 Oct 2017 12:15
by Rudolph
Re: My '98 GU 4.2 TD
Posted: 29 Oct 2017 15:46
by ces
Ai, slegte nuus!!! Sterkte
Re: My '98 GU 4.2 TD
Posted: 15 Nov 2017 05:51
by Michael
Ok so finally got the engine out and stripped.
The engine had a severe piston failure on no.3 and cracked the whole piston in half. It also had huge amounts of blowby which unfortunately caused damage on the sleeve as well.
So the future for this engine is a complete rebuild.
Block and cylinder head is going to the engineers this morning.
Re: My '98 GU 4.2 TD
Posted: 15 Nov 2017 07:36
by Wilkie
Michael just for interest sake...what do you think has caused it !!!
I would like to see the spray pattern of the injector on that cylinder. I think that injector were washing down the cylinder when the engine wasn't running and started picking up ,also the raw diesel on initial start up was hitting the piston and started to crack

Re: My '98 GU 4.2 TD
Posted: 15 Nov 2017 08:27
by ricster
Wow .... That is one ugly failure !!!
The hole that it left in the piston looks very similar to the hole in the piston on mine when I had the failure on my motor many years back. I believe that it was due to a dripping injector, as I also had not high egt's or water temp, just a constant drip causing a hotspot and eventually the burn through. My piston however never cracked like that, and I still droove my Iron Maiden home from Botswana to Alberton ( 550Km ) with the hole in the piston. So I think Wilkie is onto something there...
Here is a pic of what mine looked like for comparison
Re: My '98 GU 4.2 TD
Posted: 15 Nov 2017 10:33
by Michael
Errol/Cedric, the injectors received new tips and were calibrated when Dustin did the turbo conversion so I dont think a faulty injector caused this. If this was a direct injection engine I would highly suspect the i jector, but not so much for the indirect injection. The injectors will however be tested to make sure
Also the "flame front" that comes out of the precombustion chamber is directly aimed at the "mushroom" on the piston head, so there is no way the combustion can create a hotspot on the area with the hole in.
If I have to bet money I would say at some point pre turbo conversion this piston had very high EGT's and was weak compared to the others. The turbo just pushed it over the limit.
Re: My '98 GU 4.2 TD
Posted: 15 Nov 2017 11:51
by ces
Ai eina tog daai lyk aaklig!
Michael, dink jy die blok en top is red-baar? Hoop so. Met nuwe binnegoed sal hy weer jare kan gaan!!! (Ek het 'n ou John Deere 8430 op die plaas wat in 2008 kompleet oorgedoen is. Probleem daai tyd was om 'n goeie blok te kry, myne was beyond use. Nadat ons daai hekkie oor is, kon die res redelik maklik gedoen word. Daai trekker loop nou nog, enjin klink so mooi soos 25 jaar gelede!)
Sterkte, behoort 'n interessante een te wees
Re: My '98 GU 4.2 TD
Posted: 15 Nov 2017 12:17
by ricster
Luckily the TD42 blocks are pretty strong so popping out the old sleeves and putting new is not a problem at all. I think Michael now has more than sufficient experience in this department....hahaha.... They are also easy motors to work on, except for the weight

, just parts are expensive unfortunately.
I think Michael will have that motor up and running very quickly. I assume the head is still looking good? If so its a matter of popping out the old precoms and putting new ones in and machining them flat, and then Bobs your Aunty....hahaha.
I also don't think that this was something that happened instantly, but was building up to the failure over a loooooong time. We will never know really what caused this, much like mine years back. I was under the impression that a dodgy injector injector was the cause of my motor packing up, but it is almost impossible to say for sure. Maybe like Michael said the damage was from years before from a dodgy injector and when Dustin replace the injectors it just gave the engine an extension of life without even knowing. Dustin, and the new owner, that is really crappy luck my friend. I feel your pain and frustration. But soon it will be running better than before !!
Re: My '98 GU 4.2 TD
Posted: 15 Nov 2017 13:20
by Michael
Christoph, I believe the head is still fine (except foe the precoms which can easily be changed) and as Cedric said the blocks are quite tough and its really straight forward to have them resleeved.
And yes its really not easy know exactly what the cause was except the weaker NA pistons not holding up.
Must say that I have opened some really sad turbo engines that ran very high EGT's and none of them ever cracks a piston. They seize up and distroy the block but have not found one cracked turbo piston to date.