4WD Systems has been repairing & reconditioning 4WD Diesel & Petrol Engines for over 30 years. Our process is to fully disassemble, comprehensively inspect all components and replace or recondition any part our qualified technician deems too worn for reuse.

We ship engines all over Australia, many to work site environments. Most of our technicians have worked in the petroleum and mineral exploration industries, hence understand the cost of interruption due to part failure.

Following is a list of pertinent points relating to our engine rebuilds:
Dis-assembled and reassembled by the one mechanic
Hot tank chemical clean all components
All parts are checked for tolerances, alignment and wear
Block machine bored & honed, resurfaced, main tunnel check/machined
Crankshaft tested for straightness, crack tested and reground/linished
Only use OE quality Japanese components
New pistons, gudegon pins & rings
New mains, thrusts, conrods & cam bearings
All bearing clearances ‘plasti-gauged’ on assembly
Conrods checked for sized, straightness and new bushes
Overhauled head – pressure tested, faced, valve grind, new stem seals
New head bolts – if required
New water pump
New welsh plugs – as required
New timing belt – as required
All gaskets and seals replaced

In-house Fitting includes
Radiator clean
Silicon oil in fan hub
New Hoses, genuine Thermostat, Oil Filter, Running In Oil & Coolant

Supplied complete with change over injector pump & injectors or use original
Injectors overhauled, new nozzles and set for turbo application as applicable
For Non-turbo vehicles a turbo kit can be fitted
Balance engine components

1HZ Internal Upgrade
When the time comes to rebuild a 1HZ engine you may want to consider fitting factory turbo equivalent pistons. You can use good quality 1HZ pistons in conjunction with an aftermarket turbo and this will be no problem, but the 1HDT will take a lot more heat… more fuel… more boost.

To change to the turbo type, you have to use the 1HDT rods, they have a larger gudgeon diameter, there is no mistaking the difference.

The 1HDT type have the compression bowl in the top, where as the 1HZ are flat topped, so we use a 1HDT equivalent piston, 1HDT temperature tolerant, but 1HZ shape.

Hope this is not to confusing!

We have done this upgrade on a number of 1HZ rebuilds, it works really great in conjunction with high boost Turbo Kits with 3″ Exhaust and Intercooler.