It was time to do my timing belt along with the water pump. So I thought I write a DIY for this.
I took the pictures during the reassembly process since everything was cleaned at that time and thus looked clearer. So don't be surprised if you find the exact same picture during removal and reassembly.
I hope someone will find it useful.
Some stats about the car:
1995 Rolla, 4AFE with manual transmission, 280k kilometers. Bought her 8 years ago with 100k on the clock.
First a few words about the dependencies between water pump and timing belt. On many engines, the water pump is driven by the timing belt. If the pump seizes, it destroys the timing belt which potentially causes serious damage to the engine (interference engines, 4AFE is not one of them though).
The timing belt on 4AFE however, handles just the timing, nothing else. Meaning that as far as timing belt is concerned, the mandatory items are the belt itself and its tensioner.
The water pump is driven by an external accessory belt. No need to change the water pump along with timing belt to ensure the belt's safety. But, in order to change the water pump, the timing belt has to come off because of the way things are put together. If one chooses to do just the water pump, the only step that is not necessary to perform from the timing belt job, is separation of the engine mount in order to remove the belt and put a new one on.
The water pump lasts fairly long, 200k kms is no problem, up to 300k kms there is a fair chance it will hold.
Beyond 300k kms is pushing it. When I removed mine at 280k and turned it by hand, it squealed quite a bit
from the bearing.
Valve cover has to come off for this job, so I checked the valve clearances. Specs are 0.2+/-.05mm for intake and 0.3+/-.05mm for exhaust. All were within specs on the lower side, intake somewhere between 0.15 and 0.2mm and exhaust 0.25-0.3mm. Engine is not abused, but the tachometer does not collect dust at 5000RPM either
And this is how a Rolla valvetrain looks like after 280k kms.
Check that you can remove the crankshaft pulley. The bolt is usually very tight. There is no point in disassembling anything else before knowing that the bolt and pulley can be taken off. Normally the pulley should slide off without a puller. Check it out and get necessary tools if there is trouble.
When changing the water pump, there are a few ways to handle coolant. If you are certain that the bolt for draining the engine block is not going to snap, then drain the block. In other case (the more probable one) one can just let the coolant flow out when the pump is disconnected from the block and the head. A little less than 2 litres of coolant will flow out. The engine will have to be wiped clean or rinsed with water to clean that up. This is much easier though than fighting a snapped drain plug.
There is a third option as well and that is to replace the antifreeze with plain water, just for the water pump
job. Thus avoiding having to clean up the mess from the coolant that flows out. Especially if one is due for coolant replacement anyway.
1. Loosen the bolt that holds the crankshaft pulley.
Raise the front of the car, put it on jackstands.
Remove the passenger front wheel, remove the splash guard.
Get a 17mm socket with a long ratchet. Like two feet. You will need all the torque you can find. Or an air impact gun.
Hold the crankshaft stationary. If you have a proper manual
transmission, have an assistant engage 4th gear and press the brakes, while you loosen the bolt. Otherwise a tool can be fabricated and bolted to the pulley or one can wedge a large screwdriver into the teeth of the flywheel.
2. Disconnect the battery. Alternator has to come off and you do not want to risk shortening anything.
3. Loosen/remove the pulley bolts from the water pump. If you can get a wrench in there. Very unlikely though. Moving away the water pump pulley helps removing the middle timing belt cover later on. But is not absolutely necessary.
Remove the accessory belts. Alternator, AC compressor (if equipped) and power-steering pump.
4. Disconnect the wires from the spark plugs.
5. Unbolt the washer fluid reservoir. It has to be moved aside to get the long upper bolt from the alternator out. Just one bolt. Then wiggle it out, one stud at the bottom and one on the side.
6. Remove the two 10mm bolts (one circled, the other on opposite end) that hold the narrow cover over
the alternator wiring.
7. Unbolt and remove the lock bolt beneath the alternator. Loosen the upper alternator bolt. Swing the alternator up a bit and disconnect the wire from the engine block. Then remove the upper bolt and the whole alternator and put it aside on the intake plenum. There is another wire hanging loose in the picture, normally it is not there. It goes to an oil temp sender I installed.
8. Disconnect the vacuum hoses from the valve cover.
Undo the four 10mm nuts (circled above) that hold the valve cover. The washers have rubber/sealant under them to prevent
oil leaks around the studs. Washers can be pried a bit with a screwdriver and then unscrewed from the studs.
The valve cover may be stuck, put a piece of wood to it and tap it a bit with a hammer.
Do *NOT* damage the mating surfaces while prying on it. It is easiest to pry it up at timing belt end (left in the picture),
as it has a bit of flange hanging out there.
9. Turn the engine clockwise by the crankshaft pulley bolt and set it at No.1 cylinder Top Dead Center (TDC)
on compression stroke.
The notch at the crankshaft pulley should align with the 0 degrees mark, all No.1 cylinder valves should be closed
and the hole (circled) in the camshaft sprocket's spoke should align with the notch on top of the camshaft bearing cap.
10. Remove the crankshaft bolt and pulley. Remove the idler pulley for AC compressor, just a 14mm nut.
11. Remove the timing belt covers. All are held with 10mm bolts. Some bolts are shared between covers.
The top cover comes off easy. The middle one has one bolt very close to the bracket for idler pulley for
the AC compressor. Remove the bolts from lower cover as well. Removing the middle and lower cover is a bit of a pain.
Mostly because the middle cover has to be wiggled out from behind the water pump pulleys.
Work the middle and lower cover together to get them off.
The rubber plug in the lower cover hides the bolt that holds the timing belt tensioner. No need to remove it.
12. Unbolt the power-steering pump bracket (2x 12mm bolts circled). Remove the pivot bolt at the bottom
of power-steering pump.
The pump will have to be moved aside to clear the water pump out of the engine bay. Watch PS pump's hoses, especially
two vacuum lines underneath.
12. Slide off the timing belt guide. Unbolt the tensioner (10mm). Slide off the timing belt.
13. If the timing belt is to be reused, move it out of the way so it will not get contaminated by engine oil
or coolant when water pump is disconnected.
To remove the belt, the engine mount needs to be separated. Support the engine from underneath at the oil pan
with a jack. Put a wooden block between the pan and the jack.
Separate the engine mount, one bolt from the top and two nuts from below. I think they all are 14mm.
Lower the motor until the studs in the engine mount clear the holes so that the timing belt can be slipped through.
Most likely they won't though, and the engine mount will have to be pried up. I used the tool showed in the picture
below. It opens and closes when the handle is turned. It takes some time to separate the mount enough.
Surely one could just cut the old belt, but I prefer to try and get it out in one piece. This gives a bit of
confidence that one will be able to put the new belt in as well
If the water pump is not to be replaced, go to step 21. Otherwise just remove whatever you used to pry up
the mount, so as to not keep the mount under unnecessary pressure.
Water pump replacement
14. Water pump is bolted to the engine block with three 12mm bolts. Two of them circled in the picture below.
The third is above the one circled in red.
Then the pump is connected with a short (around 4-5 inches long)
hose to an elbow pipe that goes to the head. *DO* replace that hose. It is easier to remove the water pump
from the engine bay if it is disconnected from the elbow. Easiest way is to just cut off the short hose.
Then install the new hose on the elbow first and after that, insert the water pump into the hose.
Put the hose clamps on before inserting the water pump.
If you decide to remove the elbow as well, e.g. to replace the gasket between the elbow and the head,
the description is below.
It is a metal gasket covered with thin layer of rubber-ish compound.
Removing the elbow.
Disconnect the wire from the temp sensor for the temp gauge. Remove the small nut that holds a plastic
wire harness to the pipe. Remove the bolt (between intake pipes for #2 and #3 cylinder) that holds that
plastic harness to the head. This is to be able to move the harness a bit so it can be unhooked from
the elbow. There is a second bolt between #3 and #4 cylinder as well, but that is really awkward to get at
and can be left alone since the harness can move enough anyway.
Unbolt the oil dipstick and remove it. Plug the hole to the oil pan with some rag to prevent
stuff from getting in there. Especially coolant. Unbolt the elbow from the head, two nuts. Remove the elbow.
Old water pump
As can be seen the coolant leaked a tad. No wonder, considering the shape of the o-ring between the pump
and engine block.
New water pump connected to the elbow. Just for reference, as said above, the elbow goes in first (if removed),
then the pump is connected to it. Note the two hose clamps. One for the elbow, the other moved away
to allow the insertion of the pump.
15. Remove the o-ring from where water pump meets the engine block (circled below). The o-ring is hard as rock and
has to be carefully pried out from the groove. Do not damage the groove surface.
Clean the mating surfaces with some fine grit sandpaper.
16. Remove the pulley from the old water pump and put it on the new one. If you were able to unbolt the pulley
from the old pump *before* removing the pump from the engine bay, leave the pulley loose, to make it easier
to put the middle timing belt cover back on.
17. Put the elbow back on with the short hose installed on it. Leave the elbow a bit loose on the studs coming
from the head to have some room for wiggling it while reconnecting the water pump.
Push the water pump into the hose.
Put a new o-ring into the groove where the water pump meets the block. Do *NOT FORGET* that o-ring.
And *DO NOT* damage it while putting the pump over it. The o-ring falls out of that groove easily,
so do not squash it.
18. Tighten the 3 bolts sequentially a bit at a time.
19. Tighten the elbow to the head.
Tighten the plastic wire harness to the elbow and to the head. Reconnect the wire to the sensor for the temp gauge.
Put back the oil dipstick.
20. Put back the power-steering pump and bracket.
21. Slip the new timing belt through the engine mount. Put the mount together again. It can be a bit tricky
to get the studs into their holes. Moving the engine up or down with the jack can help. Lift the engine with
the jack until the mount is back together, then put back the nuts and the bolt.
22. Put a little high-temperature grease on the belt tensioner pivot stud and the surface where it is bolted
to the engine (circled). This way the tensioner can move easily when it will apply pressure to the timing belt.
23. Put the new tensioner on and its spring. Move the tensioner to the back as far as possible and tighten it
to hold it in that position.
24. Put the crankshaft sprocket back on. Put the timing belt on. Start at the crankshaft and then put it
on the camshaft sprocket. Have the slack on the portion of the belt where the tensioner rides.
Put back the timing belt guide, with the cupped side facing out.
25. Loosen the tensioner and let it push on the timing belt. Slowly rotate the crankshaft clockwise
(temporary install the crank pulley bolt and use a wrench)
and as soon as the camshaft starts rotating, tighten the tensioner.
Rotate the crankshaft slowly two complete revolutions and check that everything aligns properly when
no.1 cylinder is at TDC at compression stroke. Hole in the camshaft sprocket must align with
the notch on the bearing cap and crankshaft pulley notch must align with the 0 degrees mark on the timing cover.
If not aligned, go back to step 23 and move the timing belt as appropriate to get things aligned.
26. Put back the timing belt covers. As with removal, the middle and lower covers require a bit of wiggling.
27. Put back the idler pulley for AC compressor belt, if equipped.
Put back the crankshaft pulley. Hold the crankshaft stationary and tighten the bolt.
28. Pour out any oil from the valve cover. Wipe clean the gasket.
Put a thin layer of RTV sealant along
the gasket. Put small dabs of sealant on the sharp corners where the gasket goes over crankshaft bearing caps
near the sprocket and distributor. Put a thin layer of sealant on the spark plug tube seals.
Do *NOT* overdo the sealant or you will have dabs of sealant fall into the oil inside the valve cover, potentially clogging oil passages.
Another option could be to just put a new valve cover gasket, depending on the old one's condition. Then the RTV sealant would only be necessary on the sharp edges. Either case, do *NOT* overdo the sealant. Do not let the sealant to dry too much and put back the valve cover within 4-5 minutes from sealant application. Make sure *NOT* to get any oil on the mating surfaces or else the gasket will not seal properly and oil will start to leak.
29. Reconnect the vacuum hoses. Put back the alternator. Reconnect the wire to the engine block.
Put back and tighten the power-steering pump belt,
then the AC compressor belt and finally the water-pump and alternator belt.
Reconnect the spark plug wires. Put back the plastic cover over the alternator wires.
Put back the washer-fluid reservoir.
Put back whatever I forgot to mention
Check that no tools are left in the engine bay.
Top up the coolant. Reconnect the battery. Fire it up.
Check for leaks.
Depending on how the coolant was handled, top it up, or replace the water with proper
Bring the engine to operating temp, wait for the radiator fan to turn on and some pressure to
build up in the cooling system. Check for leaks. Let it cool off, top up the coolant, put some in the overflow
tank as well.