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Re: 99 td42 head cracked
Posted: 24 Nov 2012 08:00
by Peter Connan
IT seems that current theory is to work a new engine fairly hard, but paying special attention to engine temperatures and not using the engine at constant speed and load for extended periods.
The requirements for the rings and bearings are almost opposite. The bearings need to be kept cool and not worked too hard so that they can bed in nicely, so that in later life a thin, uniform oil film is maintained for lowest friction at lowest oil pressure, while the rings need to scrub aggressively so as not to glaze the bores, which will cause high oil usage and a smoky engine.
This is difficult to get right, and here is my main reason for preferring the second-hand engine route. As far as I am aware, the critical first run-in period on modern cars is achieved on an engine dyno in the factory, before the engine is installed in the car. By experts and according to a well-proven procedure.
Re: 99 td42 head cracked
Posted: 24 Nov 2012 19:58
by dieselfan
Thanks Peter I'm confused then as to why do all manuals say DONT put a load or tow for first 800km and no 100% throttle for first 1600km? They mention make use of rev changes and in bold NO 100% throttle.
I was told on some cars the injectors have a bedding in material that if gunned from day one breaks non uniformly thereby having inconsistencies between the injectors, plus temps and oil usage.
On my old Chinese 125cc scooter myself and 4 others at work purchased. I was the only one to run in via the manual and never had any leaks nor oil usage in over 4 years, plus I used to average 52km/l. Whereas theirs used a pint per month and around 35km/l. I used to redline mine all the way to work. I'm quite heavy ;).
On my last Renault Megane diesel I ran it in via manual as well and at point of sale on dyno I had 28nm more than two other Meganes with around 9kw more. Once again why would the manuals specify in big BOLD letters the run in schedule?
Re: 99 td42 head cracked
Posted: 24 Nov 2012 20:06
by Peter Connan
Cos the process is not completed on the engine dyno, only the most important first section.
Stay with the manual.
Re: 99 td42 head cracked
Posted: 24 Nov 2012 23:35
by ricster
Andre... If they are making up a radiator for you, consider this... I have a MUCH bigger radiator fitted in mine. I was told it is a radiator from a Cabstar... but can't varify. Grant on the forum had a radiator leak while we were cruising Lesotho in his GQ. His water temps would climb when working the motor on the old radiator. He had a new and much bigger radiator fitted, and the water temps are 100 perfect and don't fluctuate much now. I'll look for the link and post it here for you... ( you won't regret the bigger radiator )
Re: 99 td42 head cracked
Posted: 24 Nov 2012 23:41
by ricster
Re: 99 td42 head cracked
Posted: 26 Nov 2012 08:26
by ricster
So.... so ....so .... any news???.... just kidding.
Keep us posted mate!!
Re: 99 td42 head cracked
Posted: 26 Nov 2012 15:07
by Andre Steyn
Good afternoon everyone
ok so far pistons rings and sleeves I'm able to get the 2.7turbo model ones from AE. The head is priced at R16674,61 FOR new bare head for the td42t, I also have the option for a head from a place in hennops they're willing to give a 1year guarantee, for R7500?(any suggestions on the head and Pistons) Having a manifold built to suit the turbo and I'm going to pop in a garret turbo a nice big intercooler.
Re: 99 td42 head cracked
Posted: 26 Nov 2012 15:32
by ricster
ooooohhh eh eh.... I'm scared of non genuine heads.... you are welcome to have mine... with the cracks at the no2 and 5 cylinders.... I just don't trust them...not with a 22 or 23:1 compression ratio !!!
Is that R16674,61 head from Nissan? The Nissan head will also be bare with precoms fitted and skimmed. Contact Mark White Nissan in Bryanston area ( (011) 840 1960 ) Fight for a 10% discount.....
Pistons... your choice mate... I followed advice I got from Frans and used the Alfin type rings and pistons, so I don't know if AE make them... but they are working for me and was told that they are meant for turbo diesels
Is your Patrol currently not fitted with a turbo?...
Re: 99 td42 head cracked
Posted: 26 Nov 2012 15:57
by Tinus lotz
Raka has a 4.2 motor that needs att still in one piece mabe get it and see if heaad is ok

Re: 99 td42 head cracked
Posted: 26 Nov 2012 16:07
by ricster
This is the Nissan Part no for the head
Nissan SA part no 1103963T02