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How To change Trafic 1.9 dci 100 Timing belt

18K views 2 replies 3 participants last post by  Joegrey  
#1 ·
Here’s what I did for anyone wanting to give it a try.

Disconnect battery.

Jack up and support vehicle on axle stand.

Remove undercover from engine and undo hose circlip on l/h side or radiator and drain into a bucket. Remove cap from expansion bottle to help drain it. I also undid the bleed screws on the pipes that pass through the bulkhead.

Remove r/h wheel, plastic wheel arch cover and inner plastic cover which protects the auxiliary belt. (I didn’t know it was called the auxiliary belt but it’s the one that snakes back and forth around the bottom crank pulley wheel and drives the alternator)

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Crankshaft pulley and auxiliary belt.

I cracked the nut on the crank pulley (the bottom one with the big wheel in front of the sump). I used an impact gun for this. I bought a cheapo one on eBay a few years back to change the brakes on my Ifor Williams trailer.

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Auxiliary belt tensioner position.

I used A 16mm socket on a breaker bar on the nut on the auxiliary belt tensioner and pushed upwards (clockwise) to release tension to slip the belt off and remove it. ( took me a while to figure out how to do). Once belt was out of the way undo the center nut on the tensioner and take it out. It makes it much easier to get cam belt casing out.

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This is the nut to push on to release auxiliary belt tension. The nut below holds it in place.

Undo, ease off and remove crank pulley.

Support engine at r/h end with a Jack and a block of wood to protect sump then undo and remove r/h engine support.
Once the support is out of the way I undid the top 2 10mm bolts holding the cam belt casing and eased it back to see if there was any mark on the engine marking top dead center.
(The case is flexible and fairly fragile so take care with it.) In this case there was a mark. I could also see the white dot on the camshaft wheel which was virtually next to the tdc mark. I know that there is a small hole in the cam belt casing (see pic) through which you can see the dot or mark on the camshaft wheel but you need a mirror or something to be able to see into it and I didn’t have a small one available.

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Hole in cover and tdc mark on camshaft. Lining up mark through the hole should give you tdc.

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Hole in case and tdc mark on camshaft.

I used a socket on a breaker bar to move the camshaft forward a tiny bit to line up the dot on the camshaft wheel with the dot on the engine and then checked the position on the crank pulley. It looked correct as it should pointing from about 25 to to 5 past ish.

Remove remaining two 10mm nuts and ease cam belt casing out downwards.

I used a tippex pen to re-mark the tdc dots on the camshaft and the engine block as well as the wheel tooth either side of the belt at that point. I then repeated that with the fuel pump wheel and the crankshaft. So everything was well marked before the belt came off.

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Bottom is crankshaft, left hand side belt tensioner, right hand side water pump and far top right is fuel pump. Out of sight at top center is camshaft.

Undo central nut on tensioner and remove belt. Remove tensioner.
Remove pump. It’s likely some coolant with spill out so have a bowl handy.
Fit new tensioner.
Fit new pump. The two shorter bolts go into the recessed holes on the pump. I used a bit of high temperature silicone to hold the gasket in place on the pump and also squeezed a bit onto the water pump bolts as they went in (no idea if that was useful or not but it made me feel happier). Did everything up to recommend torque.
Fit new belt. It came with a mark on it for tdc and for the crank keyed slot which to my pleasant surprise actually did line up. I lined up those two first and held the cam belt in position with a clothes peg then smoothed the belt as I put it onto the fuel pump making sure the marks hadn’t moved.
Once belt was on you need an m6 bolt to tension the belt. There’s a hole in the tensioner that you pop the bolt into and wind it up to tension the belt. If you have all the gear there’s a special tool to pre tension the belt then another to listen to the frequency of the tightened belt to tell you if it’s tight enough. I had neither but followed others advice and used a guitar tuner on my mobile to check the frequency when I pinged the belt between the tensioner and the crank. It’s like plucking a guitar string.
It should be about 95hz this time round.
So you loosen the tensioner and wind in the m6 bolt, tighten the tensioner and pluck the belt with phone held close to it until you get to 95hz.
Then you wind the engine over a couple of turns. I did it with the breaker bar on the camshaft. I don’t know if that’s how it’s supposed to be done but that’s how I did it.

Check that all of the tippex marks are correctly and accurately aligned. If they’re not then the belt will need to be moved till they do.

Hopefully they line up so then run through the tension setting process again. Check reading tighten and check again that belt is at 90hz this second time round.
I don’t know how may time I ran through this but probably too many. Every time I checked the frequency was good and the timing marks were good.
Once happy, remove the m6 bolt and replace the cam belt cover.
Re connect the radiator hose and fill the expansion bottle and leave to start filling.

Re-fit crankshaft pulley and bolt. Your supposed to tighten it to specified torque then turn it on clockwise another 115 degrees. I marked the bolt with tippex at 12oclock and use a protractor to add on 115 degrees then marked that with tippex so knew how far round to rattle it.

Re-fit the ancillary drive belt pushing up on the tensioner to slot it into place. It looks more complicated than it is as it really can only fit one way if you line up the belt grooves and roller.

Re-fit engine mount to specified torque.

Top up coolant.

Re-connect battery.

Cross fingers and fire up the engine.

I left it ticking over for 15 minutes topping up the coolant as needed and bleeding the air.

Replace plastic covers etc.

Hopefully I haven’t missed anything out and maybe this will help someone who would like to have a go (or as in my case can’t afford to pay someone else to do it).