Fabia 1.2 AZQ timing chain replacement.

Hi all,

I thought I'd post my experience of replacing the timing chain on my Fabia 1 with the 1.2 AZQ three cylinder engine.

It's always been a very reliable car and a great starter in all weathers despite constant central locking problems and sporadic suspension rattles. Last week I got in the car and it wouldn't start, it just churned over and over on the starter. I'd used it a few times during the day and it was fine then. I tried a couple of more times then left it half an hour in case I'd flooded it. I tried again later and still the same, it didn't even try to start. I went in the house, got on the internet forums and pretty quickly determined my timing had slipped. The next day I removed each metal cap over the end of the camshafts (not that easy as the inlet one is recessed) and with cylinder 1 at TDC could see that the groove in exhaust camshaft was at 45 degrees (20 to 2 on a clock face) compared to the horizontal position it should have been in matching the inlet cam.

I got a Febi modified chain kit (30607) and a locking tool kit from eBay.

It's not a job you can do on your own really as you need someone to hold various pulleys and sprockets steady as you undo or tighten them but isn't that bad if you do things methodically and with care.

For starters it took my friend and me nearly half an hour just undoing the mega-tight 18mm bolt in the middle of the crank pulley. At one point we even had a trolley jack under the tommy bar and extension to impart more leverage and it was just lifting the car. It finally went by pulling forwards from under the front of the car. Why they don't just put four bolts in like early VW group cars I'll never know. The sump isn't too bad but some of the many 5mm allen headed screws are obscured slightly by the exhaust downpipe. You can get at them with patience but it's awkward. A long ball-headed 5mm allen key would have been ideal. One of the screws right at the front had a damaged head but because there was a projection on the engine casting right in front of it I couldn't get the mole grips on it. The screws have very shallow heads and have a shoulder on them too so there's nothing to grip. Another poor design. It eventually lost its grip when I carefully tapped it round with a small sharp cold chisel. 

We took off the long alternator belt next but should have left it on as it makes it easier holding the water pump pulley steady to undo the three 6mm allen screws. The alternator is a very tight fit on the engine and needs a fair bit of careful levering and twisting to get it free. 

Removing the crank position/speed sensor is an absolute **** of a job. It took me half an hour just trying to locate it. It's right below the inlet manifold near cylinder number three and extremely difficult to access. I found it best to lie on my back and reach up above the engine side drive shaft. You can just see the sensor but not the 5mm allen screw that holds it to the engine so it's all done by feel. I eventually managed with a 6" long extension bar on a 1/4" drive ratchet. Again I think a long ball headed 5mm allen key would be better as you can only get at the screw head at a slight angle. 

The engine mount has to come off next and as I didn't have an engine support bar I had to support the engine from underneath on a jack. There's room to put a piece of protective wood between the oil pump and exhaust downpipe to rest on the jack.

Once all the various screws and splined bolts were removed (it's easy to overlook the recessed 5mm allen screw above the crank pulley) the timing chain cover came off with no problem.

I was worried that some valves might have been bent so with the locking tool inserted through the crank speed sensor hole into the flywheel and the other in the inlet camshaft we undid the bolt on the exhaust camshaft sprocket which then turned itself to almost the right position to insert its locking tool. We then nipped the bolt up and screwed a compression tester in turn into each of the cylinders. Each hand turn of the engine needed the usual force to get it up to the compression stroke with all the expected hissing sounds and all three went up to forty pounds so we assumed that the valves were indeed all closing properly.

To undo the very tight camshaft bolts we had to make a steady bar tool from a two foot piece of sturdy angle iron with a couple holes drilled in one edge with two M10 bolts fitted so they could be inserted between the holes in the sprockets.

The big oil pump sprocket which has to come off has a flat in its mounting hole with a corresponding flat on the mounting shaft so watch out for that. You're supposed to renew the 13mm bolt but one wasn't included in the kit so we used it again.

Fitting the new chain, guide rails and tensioner and replacing everything was all pretty straight forwards. After finally filling the sump with fresh oil in hindsight I would turn the engine over a dozen or more times by hand to prime the oil pump. We used the starter and the engine made an alarming rattle for around ten seconds until the oil pressure had built up. The good thing though is the engine started immediately and got quieter and quieter till it settled into a nice idle. Phew!

I've used the car for work today and I noticed the idle speed is slightly lower at 800rpm but it's much smoother now. I've had the car nearly five years and the idle has always been a tad uneven which I put down to the three cylinder design. Anyway it all seems fine!

I think the whole job must have taken around 12 hours in total. Tiring, awkward at times and butt clenching at others but satisfying once it's done.

Good luck!

Andy.