Hello all

This forum has been great for me with some glitches on my just-run-in (126k) new (2000) Octavia diesel. So here's an account of my recent cambelt change for anyone considering doing it DIY.

1. Is it do-able by an amateur? Yes, if you're sensible, fairly experienced (eg you can do brakes, or change the oil, without being fazed) and nothing goes wrong (but that applies to everything).

2. Can it be done on the street? Yes.

Some notes:

- I used the Haynes manual. It was of some use but not critical.

- I didn't use the timing tools. I bought one but it didn't fit - so be careful about which one you buy if you really want to time the camshaft. Laser do about 5 types.

- I did use the tensioning wrench, which was about £12. You could use circlip pliers but it'd be a fart on. You might be able to rig one out of a grinder disc spanner.

- Getting the cam cover off was a giggle. I used a bit set with a 1/2 sq drive and was using just the bit (without holder) turned by a spanner in the rear right corner of the cover. Access is awkward.

- We did two cars; one took 12 hours as we felt our way through the job. The 2nd took 5hours without hurrying. Having one person would make a little difference to the time required but not much, and no part of the job needed 2 people.

- I changed the water pump (you'd be crackers not to) and the poly-V (AKA ancillary / serpentine / drive) belt.

Strip down part 1.

Flat surface, handbrake on, car in reverse gear – loosen right front wheel bolts. Jack car up on to axle stands. I used car’s own jack, and put a load of wood blocks under chassis rail and eased it back down on to these so both jack and timber had load on them to keep them secure where they were.

Trim: Remove undertray (I've left mine off for ease of oil changes). Remove wheelarch liner, small corner piece and vertical shield. All torx screws that came out fine. The flat metal star fixings on the side panel down by the undertray – I tried to rotate these but it’s best to give them a good strong pull straight down. They don’t appear to take any harm from this and go straight back on the same way and it’s easy.

Whilst you’re down there, take the tension off the crank pulley bolts and then use a spanner or socket to take the load off the ancillary belt tensioner, and slip the belt off. If you don’t have a Haynes or other diagram, note where it goes first – it’s tricky to figure out its run once the belt’s off. Note the condition – if there are cracks between the Vs, get a new one for when the job goes back together. Don’t panic if you don’t have one to hand, it's easy to do another day. Leave the wheelarch liner off and drive to the parts shop afterwards.

Once the belt’s off, finish taking crank pulley bolts out and take that off. It might need a tap to release it from the crank. Note the way it’s mounted first – they are supposed to go on a certain way (mark the hub & inner flange of pulley to be certain); n fact I think they will only go on a certain way, the bolt holes aren't on a circle. Remove the nut holding the corner of the intercooler-to-turbo pipe on. It’s useful but not essential to unclip the pipe at the elbow and the other (intercooler) end and take the pipe off, leaving the bit up to the turbo still on. Stuff a clean rag or ball of paper in any open hose ends on the car to stop stuff getting in (er, remember to remove before reassembly).

Up top – take air filter to manifold hose off at manifold end (up behind engine at top), unclip sensor plug and take housing off wing (2 bolts 10mm). This gives you sight of the flywheel port.

Take vac pump off end of camshaft cover, put in clean plastic bag still attached to hoses and hook out the way with string or wire. Drape a rag over the exposed end of the camshaft. [With hindsight I wouldn’t bother doing this – I didn’t use the slot that the tool goes in which sits behind the pump; there’s no other reason to take it off. Seeing the slot isn’t necessary if you can see flywheel notch and no.1 cylinder valves]

Remove right front headlamp connector – pressure on the clip on the side is needed to disengage the clasp, but careful – a bit too much and it snaps off. I used offset pliers (a bend in the jaws – v.useful for loads of things and cheap down the market). Remove 7mm nut linking indicator to headlamp, slide indicator out of wing, disconnect and remove. Remove screws holding headlamp assembly in and remove it.

Now to remove power steering reservoir (black, green cap) hoses, having lots of rags/paper underneath it when you pull the hoses off. Remove the hex bolt securing the reservoir to the wing, then using pliers, take tension off spring clips and move them back down the pipes. Do one side at a time, lifting the reservoir and pipe up vertical as soon as the connection is broken, to keep leakage to a minimum. I stuck a finger from an old rubber glove over the end of the hose and secured with an elastic band the postie kindly leaves all over our street. You can do this for both stub pipes out of the reservoir, and both open hose ends, and it’ll cost you almost one glove and 4 bands. You’ll have enough fluid left in the pipes and the pump to allow you to drive so don’t worry about spilling fluid and having to get more before you can go anywhere in the vehicle later.

Unclup wire and hoses etc from manifold to intercooler hose & pipe (big black pipe/hose that runs across the front of the engine from the back of the engine bay down behind the headlamp. Big water pump pliers to remove spring clips on hose connector at bottom end down behind the headlamp position and top end. Rotate, fiddle and manoeuvre the thing out the headlamp aperture.

Strip-down part 2.

A. Remove small elbow hose from cam cover to intake (quite tight), remove hex bolts holding cam cover on. Some can be stiff – I had to chisel one off on both cars [ie use hammer and chisel to rotate the bolt head, not chisel it clean off. If it comes to it, you could drill off the head, and this would release pressure on the threads so the bolt body could then be removed later] – and the ones at the back can be tricky. Check you’ve got the kit to do this before starting on them. I used a hex bit in a ½ inch holder for most of them, but had to take the bit out of the holder and use it with a 10mm spanner on the one at the back/left.

Engine mount.

Get a screwjack / bottle jack or some other means of lifting the engine from underneath under the sump, and take the weight off the mount by raising it. Lifting from underneath is better than having a hoist in the way above, but a hoist would be fine if that's all you've got. I used a jack from another car’s spare wheel kit, and a lump of wood to cushion the sump. I set it near the oil drain hole – the sump isn’t flat bottomed so on/near the ridge there is best. Raise it till the car/engine moves slightly – the jack has the weight then.

Unbolt the two bolts to the wing (16mm). Undo the 2 from mount to the on-engine bracket (18mm). Because I didn’t loosen the wheels off the end of the camshaft or pump, these are the only bolts I replaced since if they work loose your engine will drop (although there’ll be lots of clunks and lash in the transmission before it would come off, so you’d get lots of warning).

The actual mount comes up and away easily. You now have to get the big lump of alloy bolted to the front of the engine off and out. This is the most difficult bit of the whole job and the only bit that’s a total pain in the bot. Undo the 3 bolts holding it – they are hard to see and awkward to reach but you can get a decent swing with socket& ratchet from the wheel arch once you've got the socket on the bolt, so those aren’t the problem. Once it’s loose, you need to get it out the top. This is really tricky – a good deal of writhing, pulling, bashing and jacking up and down is needed. I got it out on both cars and back in on one without a damage, but broke a lump off the side of the cambelt enclosure putting the second one back in – so be careful.

Not far off the half-way point. Pull out plug in the spy hole on top of the bellhousing. Lift the cam cover out the way, stick a 19mm socket/long extension/long handle on the crank nut (this is a 12 point nut – most sockets are 6 point now (because they use flank drive rather than because they’re cheap, which was the case before) and turn clockwise (looking at the front of the engine) slowly. It shouldn’t be easy to turn and you’ll hear the cylinders wheezing. Look for the cams on cylinder 1 both coming off the lobes (so the ‘round bit’ is on the bottom, on top of the valves, and the lobes sticking up-ish). At the same time, look for the tiny dimple on the flywheel coming around. It’s very small so keep a good eye out and turn very slowly after the cams on no.1 come off the lobe. When this appears, line it up with the pointer hanging down from the top (and put a wee bit of white paint using a marker pen / tipex / touch-up stick on the flywheel tooth – makes finding it again much easier). When the dimple and pointer line up and the no.1 cams are in the dwell (off the lobes), you’re at top dead centre (TDC). This is your reference point. The slot in the end of the camshaft should be horizontal. If you needed to set the camshaft at exactly TDC then you use the special tool and feeler gauges. The manual says to do this – I didn’t and can’t see why you’d need to.

Get a 5.5mm drill, wrap some tape round the sharp end and stick the other end through the pulley wheel and hub. This locks the injection pump.

Change belt, water pump and reassemble. Easy!

You now have a locked injection pump, and have a reference for the flywheel (hence crankshaft) and the cam shaft won’t turn unless you help it. Time to change the belt.

I put 3 small marks on the root of the teeth on the camshaft wheel, and the corresponding top of the tooth on the belt; 2 on the injection pump pulley/belt and 1 on the crank pulley/belt.

Now release the nut holding the belt tensioner. It should spring back. Now the tension’s off, remove the 2 small and 1 large idler pulleys and the tensioner pulley. Remove the top idler first, pressing on the belt to separate it from the idler and so ensure the last ¼ turn of the screwthread isn’t damaged by the bolt being pushed sideways as it exits the thread. Carefully slide off the belt (now loose).

Put the old/new belts alongside each other. Make the 3, 2 and 1 marks on the new belt, counting the teeth in between them to make sure they are in the same position on the new belt. I used a pencil to mark the belt – solvent-free and will rub off straight away once the engine is running.

With the belt off it’s time to do the water pump. Remove 3 bolts and tap / writhe / pull and push till it pops out. If you can squeeze a flexi bucket under the front of the engine then do so, there’ll be a big splash when the pump leaves the aperture. This is the mid point of the whole job progression-wise (and past halfway time wise) – it’s all put it back together from now.

Dry and wipe clean the hole with a clean cloth (no scrappy rags - you don't want threads or other nonsense getting in the hole). Put a bit of Vaseline around the O ring seal on the new pump, ease it into the hole, making sure it lines up. It should not be easy to get in. Press it in keeping it in line (not so easy) until you can push no further. You can then use the 3 bolts to pull it in as long as it’s going in straight. Do 1/3 turn on each bolt then the next, then the next etc to avoid tipping the pump to one side as it goes in. You should not see much resistance on the bolts if the pump is going in straight. When it’s snug and home, tighten the bolts and make sure the pump pulley still turns easily. Water pump done – time to put new belt on.

Slide new belt on whilst sliding the tensioner on to its stud as well (the raised sides of the tensioner pulley make fitment hard if you put the belt on first and tensioner later), ensuring marks line up with the ones you made earlier on the cam/pump wheels. The little tab on the back of the tensioner goes in to a hole hiding at about 11 o’clock from the stud. Slip the nut on the tensioner stud and do up finger tight. Next time I'll change the stud as well but didn't this time (you get it in the kit).

Lie on the floor and fit big idler (push pulley against belt to give the bolt a clean run at getting started in the thread in the hole); then from top, fit the lower small idler then top small idler, pressing the belt a bit to give the bolts a clean run in to the hole.

Get your modified grinder spanner, circlip plier or proper tool (worth it at £12) or whatever and tension the belt. The slot and the tab aren’t easy to see when winding the load on because they’re small – make sure you look at them whilst off the car to see what you’ll be looking for whilst you’re struggling later. It might be worth dabbing a wee bit of tipex on the tab and the gap. Try fitting a small mirror at 45 degrees if you need to; remember to have the 13mm spanner close or in your hand ready to nip the nut up once the tab and slot line up.

Take drill out to unlock the pump and rotate engine 4 times by the crank nut. Find the mark on the flywheel (hence the marking earlier) and make sure the drill goes back in when the flywheel is on the mark. The marks on the belts/pulleys won’t line up now. Since the belt is fully engaged on the pulley teeth, the 3 shafts cannot be moved relative to eachother.

At this point the manual talks about dynamic timing. I don’t have the fancy stuff to check it, so my approach was swap belt like for like without loosening pulley bolts (ie pulleys always tight on shafts) and it’ll be OK. If it wasn’t then I could have it timed but it would be safe to run till then. It runs fine; if the fuel economy is the same after a few tanks I’ll leave it as it is.

Put everything back together in reverse order. Clean the cam cover gasket and mating face on the engine before reassembly (clean cloth as for water pump aperture). Fit a new serpentine (ancillary drive / auxiliary drive) belt, new bolts to mount-to-on-engine-bracket if possible (but not essential). Remember to be careful getting on-engine mount bracket back in ready for bolting up, and make sure you refill coolant system and power steering reservoir. When filling coolant, top up header tank with 50/50 antifreeze/water, run engine with cap off reservoir whilst squeezing hose to radiator. It takes a good while for the bubbles to come through.

First one took 12 hours, losing time to stuck camshaft cover bolt and sticky pump. Second one took 5 hours, not having to feel way through the manual for each stage. Would probably shave off another 1/2hr if I did a couple more. Can be done on the street; make sure the car can’t move to roll off the jack and blocks and the sump jack. Well within the reach of a home mechanic – there are no bits needing particular expertise beyond decent mechanical awareness of how to treat difficult bolts.

For a Saturday on the tools I've saved about £180-200. In another 40k miles I'll consider only changing the belt - I think 80k miles from a pump and tensioners/idlers is reasonable. Mind, if the whole kit is only another £20 I'd do the lot.

Edited 30 April, 201214 yr by topbanana

Havent read it all, but it looks alike good decent write up.

(couple of pics would be nice too, but thats just being fussy...)

Id not be surprised if a Mod contacts you about bumping this to the guides section?

well done again :-)

^{Thought it might be a bit long, but didn't know if that would be a problem. More than happy for that to happen if a Mod thinks fit.}

^{Will take pics next time - 40,000miles that is. Got engine oil, gearbox oil and brakes to do next . May add something for the brakes but the oils don't seem worth writing up.}

yeah, i havnt looked but id say theres plenty oil/fluid change write ups :-) brakes with pics might be worth doing though

Wouldnt worry about it being long, just means more details, which is always appreciated by somebody trying it for the first time :-)

Its not that bad a job, ive done mine a couple of time now. The main thing is to get the wheel off and get another jack and a piece wood on the sump to hold the engine in place when you take the engine mount off.

All the other bits in the way like the header tank and the power steering fluid tank just swing them out of the way towards the front of the car. The tensioner must be right if you mess up it will cost you dearly.

Look on youtube for how to tension a vw tdi timing belt correctly, it is best to get the pump timing checked with a vag com after too.