

1HZ Timing Belt & Water Pump Replacement Guide
WARNING: I TAKE NO RESPONSIBILITY IF YOU ATTEMPT THIS.
I have been messing about with my own vehicles for the last 25 years.
If you follow this guide, you do so at your own risk.
I will not be liable if you lunch your engine because you didnt align your timing marks correctly or check for any valve to piston contact by rotating the engine after fitting the new timing belt by hand.
The Toyota 1HZ engine IS an interference engine due to being high compression.
This means that your pistons WILL become intimate with your valves if you get it wrong.
1. Drain The Coolant
2. Remove The Top Radiator Hose From The Radiator
3. Remove Radiator Fan Shroud Bolts
4. Remove Fan Clutch Nuts From Water Pump
5. Remove fan shroud and fan at the same time.
If your 80 series has battery heat shields fitted, you will need to remove both batteries first to remove them.
5. Loosen alternator tensioner bolt and alternator pivot bolt.
Loosen the a/c tensioner pulley nut and loosen both tensioners to remove the matched alternator belts and the a/c belt.
(Yes, I'm aware I said air-conditiong when pointing at the alternator. I was tired, thats my excuse and I'm sticking to it haha)
6. Remove A/C idler pulley and tensioner assembly.
7. Unbolt the alternator bracket and remove the water pump pulley from the water pump.
Remove the timing cover by removing the spring clips and 3 bolts.
8. Unbolt the power steering reservoir from intake manifold.
One bolt at the front and two on the side.
9. Remove timing cover and align timing marks for the cam gear and injector pump.
You can do this by rotating the engine via the harmonic balancer bolt.
If you overshoot the mark, gently rotate backwards past the mark and come forward and stop at the mark again.
10. Check your timing marks and remove the timing belt tensioner and spring assembly to remove the timing belt.
Remove the cam gear as per the video instructions.
Realign if required.
11. Remove the rear timing cover backing plate.
Gently pry from the passenger side with a pry bar and use a dead blow hammer to tap it forward to release it from the adhesive.12. Replace camshaft seal.
13. Remove water pump bolts from water pump.
14. Remove water pump and water pump metal gasket.
Inspection revealed that the water pump was leaking from the front seal as well as the inspection hole.
15. Fit new water pump and new metal water pump gasket.
Make sure to refit the alternator bracket at this point.
15. Clean off any old sealant and reapply a small bead to the rear of the rear timing cover.
Make sure you add sealant into the corners as this is a requirement for fitting a new cam cover gasket to stop it leaking.
Make sure you use pre-assembly lube or some fresh oil on the inside of the seal before you refit the cover.
16. Fit cam gear and tighten to 98nm (72ft-lb).
Not 72nm!
I was definitely tired by this stage.
17. Fit timing belt as per video.
18. Bolt new tensioner to engine.
19. Fit new tensioner spring to tensioner.
In the video, I discuss the easiest way to fit the hook of the spring over the post.
Important: Rotate engine one full revolution and line up the timing marks to be certain the belt is fitted correctly before going on to the next step.
20. Refit timing cover to the engine.
21. Refit a/c tensioner and idler pulley.
22. Replace the fan clutch assembly.
If you do not need to replace it, skip this step.
23. Refit fan assembly and fan shroud.
Drop these in at the same time, while taking care to not damage the fins of your radiator.
24. Refit the matched pair of alternator belts and the a/c belt.
Important: Tension them so you have about 12mm of deflection in the belts.
25. Refit the battery heat shields and batteries.
26. Refit top radiator hose and retighten lower radiator hose clamp.
Fill with coolant and check for leaks.
Bleed cooling system and refit radiator cap.
ABN: 89 462 190 615