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Monday, May 9

Learning from the expert mechanics

Brett: After some searching, we found some Hilux specialists in Cape Town that were willing to spend time teaching me as they worked on the 4x4. I spent 3 days working with Allan Venter, Gawie, William and James at AEW Auto in Brackenfell. I highly recommend Allan - he was very knowledgeable and helpful.
Clutch – this was a big job - we took the engine out to get to the clutch (the other option is taking the gearbox out) which gave me a chance to learn a lot. The flywheel was skimmed, new bearings fitted and a heavy duty Sachs clutch fitted. The clutch had been OK on the test drive, but got worse on our practice run to Cape Town to the point where it started to slip and it didn’t disengage properly causing issues with gear changes. A clutch is definitely something to check as it can let you down with little option of fixing in the bush. The best way to test a clutch is to drive in 5th at low speed, then clutch in, floor the gas and drop the clutch – the revs will drop slowly if the clutch is slipping.
Valve Stem Seals – in cars designed before the introduction of unleaded fuel, the valves stem seals tend to go hard and leak oil. There was a small amount of smoke while the engine was cold and it was using a little oil (this is the most common cause for this engine). Many people live with this, but we decided to fix it as we plan to keep the vehicle after the trip. We took the head off and sent it to be completely refurbished.
Prop Shaft – there was a small vibration at 10km/h when we test drove the 4x4 which is caused by the centre rubber mounted bearing. On the way down to Cape Town, it developed a bigger vibration that was present most of the time, but worst at 110km/h. The likely cause is because the bearings were about to go and by taking off the weight of the canopy, the angle of the prop shaft increased to more than it had been doing for its whole life. There was about 1/2 cm of play in one of the bearings and the rollers had disintegrated. There was also a small oil leak from the transfer case which turned out to be a missing bolt.
Leaf Springs – the front springs had sagged below straight – these were reset using a 20 pound press to bend it at points 5 cm apart. These have been set slightly too high, but reset springs tend to settle down after some time – to avoid them settling too much, an extra leaf was added. The rear springs were already fine, but an extra leaf was added to take the additional load. Re-installing the front leafs took a lot of force.
Engine – taking off the head allowed closer inspection of the cylinders which are in excellent condition. The engine has no oil leaks and runs very well. We replaced the exhaust manifold gasket with a heavy duty one as the previous one had blown slightly. There are 2 valve chains and push rods to the valves – with this set up, there is no need to replace these until they start getting noisy (around 500,000km). Alan adjusted the spark timing from 15 to 5 degrees advanced to help with poorer fuel quality in some countries. We also did a general service of oil/fuel/air filters, oil change, brake/power steering/clutch fluid check.
Diff Lock – this worked on the test drive, but stopped working on our way back from Bloem. It turned out to be the power cable had broken. I learned how to debug the electrical and vacuum systems involved. The best way to test the diff lock is to lift one wheel with the gear in neutral – the wheel can’t be turned with diff lock engaged. 
Aircon – This was re-gassed and a leak fixed.
Other bits – I took the cover off the driver door and oiled up the winder mechanism that was sticking - there was also a rattle that turned out to be a loose bolt. We fixed the second tail gate chain with a weld. We welded 2 pipes onto the bumper/chassis as high lift jacking points. Alan bought the VHF radio as we wouldn’t get much use out of it and would need to licence it at every border. We siliconed the front window which had a small leak. We checked the alternator and second battery wiring. We inspected the fan, but the motor still makes some noise.
Bad Fuel Lesson – Allan suggested doing a visual inspection of and fuel before filling up – taking fuel from the bottom of the container or pump into a glass jar, and leaving it to settle, we should see if there is sediment or water.  Sediment will clog up the filters (which we are taking a lot). Water or diesel in the tank will cause the engine to stop running, but won’t cause permanent damage as it is petrol with a carburettor. Fuel injectors tend to be much more sensitive and the wrong fuel or water in a diesel engine can cause expensive damage.
Bypassing the Immobiliser – This could give us some issues on the trip and after the lesson from Alan, I can see they would only delay a determined thief by about 30 seconds. He showed me where the original wiring was cut and can be reconnected. There is also a fuel cut-off solenoid which can be bypassed.
Spares Kit – went to GoeieHoop with a list of spares to buy: spark plugs, air filter, oil filter, lots of fuel filters, top/bottom hose, heater hose, fuel hose, 3xbelts, cable ties, insulation tape, brake fluid, engine oil, fuses, pratley steel, flexoid, grey sealer, grease, Q20, hose clamps, duct tape, electrical wire, nuts and bolts.
Carb - on returning to higher altitude, the engine started to stutter - a quick call to Allan and he recommended removing one of the vacuum pipes which makes the mixture richer when you do a quick burst of acceleration - it tends to flood the engine on older vehicles and the fix worked brilliantly. There was also a rotten pipe from the fuel pump to the carb that was perished and leaking - another easy fix.

We bought an aluminium canopy, fridge, second battery and inverter from R&D Offroad in Brackenfell.

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