What are you getting for your money with a pre trip
inspection? What are good mechanics on the look out for to ensure your 4WD
makes it through that big trip?
A pre trip inspection should take around an hour and we
always start with the radiators and cooling system. Modern 4WD’s can have
transmission coolers, a/c condensers and intercoolers that can have bugs and
all sorts of muck that can impede flow to the radiator. We had a couple of
cruisers that got blocked that bad we had to remove the coolers individually
and unblock them with a gurney and compressed air. Also check the coolant is in
good condition and not water diluted and contaminated with rust or oil.
BATTERIES AND ALTERNATORS
Every pre trip
inspection should include an electrical assessment of the charging system. You
don’t need to be an auto electrician to clean battery terminals and top it up
with water but any parasitic drains or bad charge rates need to be sorted. Any
new equipment (i.e. Fridge, Spotlights etc) needs to be locally tested before
getting into a remote area and realising the alternator isn’t up to the job. Water,
salt, dirt and electrical currents all give your connections a very hard time
and regular maintenance is required. If wiring up your own accessories make
strong water proof connections. There are a variety of contact cleaners
available. I prefer WD40 or CRC5.56 together with a light scrubbing of the dirty
connections with sandpaper.
WHEEL BEARING AND CV CARE
Wheel bearing maintenance is critical for your own safety
and good reliability. Most manufacturers recommend 100000km service interval
for replacement but heavy off road driving demands this interval be shortened.
It is important to inspect brakes as well as suspension components when you
have the bearing assembly apart. There are a number of different greases
available and you have got to be certain that you use a high speed bearing
grease. If you are unsure just get down to your local bearing and industrial
supplier and they will give you the right one. They also make good bearing
packs and can sell any belts and seals you might need. The vehicle should be
jacked up and checked for smoothness and good adjustment. Also give your ball
joints a good shake and change them as required.
Left to right CV Joint Grease, Purple high tack bearing
grease (what we use), Valvoline and Mobile
blue grease(high speed bearing) Extreme high pressure grease for earth moving.
GEARBOX AND DRIVE LINE CARE
Many 4WD’s go through two or three gearboxes compared to
maybe one motor. Lack of care/leaks and bad oil are the number one killer of
boxes. In their operation they generate metal and that needs to be drained and
refilled with good quality oil at regular intervals. Upgrades like oil saver
hoses on the cruisers can save money long term if you have a failure with your
gearbox output shaft seal. Transfer case oils get a lot of steel and heat and
need to be kept in good condition. If you drain out a lot of steel it is
cheaper to get it repaired sooner rather than later when more serious damage
occurs. Most reconditioners charge extra if the core return has a hole in the
side it.
Gearbox and transmission oils in 20l packs. These containers could do 2 major drive line services on this cruiser.
ENGINE CARE
Diesel engines need good servicing or their life will be
reduced. Regular oil and filter changes are really important and also don’t
forget about timing belt intervals. Any smoke needs to be looked at and there are
three different types that diesel mechanics look out for.
White Smoke – This generally indicates partially burnt fuel
or coolant getting into the combustion chamber via the head gasket (also check
air cleaner after a dusty trip). Also with 1HZ motors when you have white smoke
on a cold start up and it clears up you know straight away that you have glow
plug issues. 1HZ motors are indirect injected and rely heavily on glow plugs
for starting. If the motor won’t fire up straight away don’t burn out your
starter because they can crank over all day and not start with out plugs. If
you get caught out in the bush with a glow plug wire fault under the dash
somewhere you can use a jumper wire from the battery straight on to the glow
plug and be able to get home. Bad fuel can also give you a white smoke if it
doesn’t stop a diesel motor. It is important to drain your fuel water separator
regularly and use some diesel conditioner if fuelling up out of drums in remote
areas.
Blue Smoke – This generally indicates oil burning and means
rings or a turbo seal are faulty. When you get a seized piston you get a
combination of white and blue as the seal on the bore is that bad there is a
lot of oil as well as not enough compression to burn the fuel.
Black Smoke – This generally indicates over fuelling or a
bit of injector dribble. In this condition the fuel is completely intact as
opposed to white smoke which is partially burnt and is doing no useful work.
This 1HZ has an aftermarket turbo and 300 000
kms on the clock. It is well looked after and doesn’t smoke or leak.
Will my older 4WD make it on that big trip?
Older style diesels are tough they can take some bad fuel
and you don’t need a scanner or expensive diagnostic equipment to tackle a
fault. If they are well looked after they can be just as reliable as their newer
counterparts. They have heavy duty rugged motors in them and parts are readily
available and as well as cheap. If you have a mechanical problem just some
common sense and basic knowledge will get you on your way. I recommend an older
style 4WD for DIY mechanics and people on a tight budget. Pajeros and Jackaroos
are good capable off roaders and can found cheap on the second hand market.
Landcruisers and hiluxes hold their value and are great 4WD’s.They are a bit
more crude but if you do break something on them you don’t have to take out a
second mortgage to fix it.
Enjoy your 4WD and keep safe
Sam
Head Mechanic
Express Diesel Service
