TD42 Turbo Conversion Project

[Michael]

In your experience, what causes the plethora off snapped cranks that the TD42 has been ear marked with in Australia?

Tell us more. Never heard of this

We have managed to snap a crank on one of our builds. This was the very powerful bakkie I built for Attie Diedericks that made 223kw on the rear wheels if I remember correctly.
We could not measure the torque correctly as we could not keep it from wheel spinning on the dyno...... not even with deflated tyres and 6 of SAC staff member on the back, but the torque was calculated to be over 1,000Nm on the crank and it just cannot take that much torque.
This is why they produce steel cranks in Aus, but I don't plan to build another engine that will produce that much power again. We also had to de tune this engine a bit to not break another crank.

[ra_01]

Thanks for posting this.

Assuming the vehicle is kitted for a touring set up; What kind of fuel consumption can we expect after a turbo conversion. I've heard about 4.2TD heating issues, can you shed some light on this?

[jakeslouw]

Thanks for posting this.

Assuming the vehicle is kitted for a touring set up; What kind of fuel consumption can we expect after a turbo conversion. I've heard about 4.2TD heating issues, can you shed some light on this?

Depends on too many factors:
- boost
- pump settings
- weight / load
- your right foot
- gear selection and revs

Yes, the TD42 is renowned for overheating issues due to a badly designed cooling system.

[Michael]

Thanks for posting this.

Assuming the vehicle is kitted for a touring set up; What kind of fuel consumption can we expect after a turbo conversion. I've heard about 4.2TD heating issues, can you shed some light on this?

The vehicle is still stock and it should give about 7,5km/L on avarage. If you can control your urge to use all the power and drive at 110km/h it will give you 8,5km/l.
The TD42 can give you sleepless nights with running hot, but that depends on so many factors which I will cover as we go.
But in short, when I am done, you will not have to worry about temps

[Michael]

Thanks for posting this.

Assuming the vehicle is kitted for a touring set up; What kind of fuel consumption can we expect after a turbo conversion. I've heard about 4.2TD heating issues, can you shed some light on this?

Depends on too many factors:
- boost
- pump settings
- weight / load
- your right foot
- gear selection and revs

Yes, the TD42 is renowned for overheating issues due to a badly designed cooling system.

In short, its the engine design that is the main cause. Its a pre combustion chamber engine, which means the combustion takes place inside the cylinder head and not on the piston. This generates a lot of heat in the head and the design is not good enough for the cooling system to get rid of that heat....... thats the long and short of it.
Even if you install the best radiator on the planet, the engine design cannot be changed

[jakeslouw]

In short, its the engine design that is the main cause. Its a pre combustion chamber engine, which means the combustion takes place inside the cylinder head and not on the piston. This generates a lot of heat in the head and the design is not good enough for the cooling system to get rid of that heat....... thats the long and short of it.
Even if you install the best radiator on the planet, the engine design cannot be changed

never had any issues with my TD27 which is exactly the same design: so I think a decent radiator should help IMHO

[Michael]

In short, its the engine design that is the main cause. Its a pre combustion chamber engine, which means the combustion takes place inside the cylinder head and not on the piston. This generates a lot of heat in the head and the design is not good enough for the cooling system to get rid of that heat....... thats the long and short of it.
Even if you install the best radiator on the planet, the engine design cannot be changed

never had any issues with my TD27 which is exactly the same design: so I think a decent radiator should help IMHO

Just a decent radiator makes no difference. We have been through many radiators and more than 2 different radiator builders that made a 3 core radiator which actually made it worse. The best radiator you can buy is the Nissan original.
Also be aware of the following, the TD42 when tuned correctly and there is enough airflow over the radiator runs great and you will not have any temp issues. The problem comes in when its really hot and you are towing something heavy, then the temps start creeping up and there is not much you can do but just manage the temps with your foot.
If it was a simple as changing the radiator it would not have been one of the biggest topics on a TD42.

[Michael]

Ok so today is piston and rings day.
Its quite a timely process, but every ring is placed inside the sleeve and the ring end gap is filled to the specification we have found to work best over the years.
The factory spec is too small and we have ran into some problems in the past. We also run the engine with more than double the factory power and for that you have to account for a bit of extra expansion from the rings.

Here I am just using an old piston with rings to press down a ring and measure the end gap.

Finally all the rings done and ready to be installed

[Michael]

So there has been some other projects that needed a bit of attention, so could not work on this build full time over the last few weeks.
But here is what happened. We have installed the new turbo pistons and everything measures up to spec.
The cylinder head was crack tested and serviced where the valves were again faced and seated and they also received new valve stem seals.
Sump was modified so the turbo oil return pipe could connect to the sump.
We use Nissan gaskets only for the cylinder head gasket and the sump gasket.

Pistons are now in their new home

Head assembled with a top mount turbo manifold

[Michael]

So now all the internal work of the engine has been completed and we can now start with the work on the outside.
Last couple of things to mention. We have tested and calibrated the injectors to 130 bar (factory spec is 118 bar) to help a bit with better atomazation.
Injector pump static timing was done and the boost compensator will follow soon.

Here is just a pic of how the engine bay looks before we get started..........