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Discussion Starter #1
How does one set the crankshaft in the right position when the camlocks are on and the cambelt is off?
I was changing cambelt and had set the engine to TDC using DTI put locks on but crankshaft accidentally got turned anticlockwise about 90 degrees not sure of the exact position it was at before belt removed and when guessing where that was and checking the DTI the needle was indicating the piston in no 1 cylinder was not at TDC and if I rotated the engine 30 degrees clockwise above my 'guessed' original position the needle was still going clockwise, but my 'guesstimate' couldn't be that far out, so unsure why DTI gave me the wrong original TDC if that's what has happened? Didn't take the crank round any further to see where the needle would stop as I was worried about interfering with valves as the camshafts are locked. So be glad of advice as to how to sort this one please? (By the way read on here that you can rotate the crank full 360 and the valves won't be affected even if the locks are on but don't want to chance that!). Just want to set the crank at the right position.
I can clearly see the crown of the piston in No1 sparkplug hole does that mean its definitely on the ignition stroke?
 

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when rotating by hand you would need considerable force to damage valves,if you are rotating with a spanner and it stops due to valve impact just rotate backwards and it will be fine.
I seem to recall on the crankshaft pulley there is a mark that lines up at approx 11 o’clock to identify no1 firing. Put pulley on get crank in about right position then DTI so it’s exactly TDC.
 

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Johnny is quite correct, turn gently and nothing gets bent. With the spark plugs out from each cylinder this is easy. Although I use a DTI, something as simple as a hand held knitting needle works. You can easily feel when the piston changes direction.
 

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Discussion Starter #4
Thanks lads I'll give it go, Its a bit of a struggle to get the new belt on over the cam pulleys the edges are sharp and will cut into the belt. I thought perhaps its best to tilt them outwards towards the wing a bit to give a more leading edge in.
 

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With the tensioner relaxed the belt should slide on to the pulleys quite easily, and with the four bolts on the inlet pulley loose it can move to suit the teeth. If more than hand force is required there's something not quite right. Sometimes the tensioner needs a wee push to get it to slide away.
 

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Discussion Starter #6
With the tensioner relaxed the belt should slide on to the pulleys quite easily, and with the four bolts on the inlet pulley loose it can move to suit the teeth. If more than hand force is required there's something not quite right. Sometimes the tensioner needs a wee push to get it to slide away.
Thanks. I'm surprised the belt fitting is that easy as I've really struggled to get it round all the pulleys the only way so far is by removing the idler putting the belt on all the other components and then carefully fitting the idler which works but I'm not happy is the right way to do it. I've moved the cam sprockets left and right in attempts to lift the belt on with no change its dead tight.
The tensioner does slide ok and I've slackened all the bolts on everything right off but Ive found it really difficult to tension the belt using the alfa tool with the peg on the end the only way I can get it into the hole on the crankcase is by pushing the tensioner pointer round with a screwdriver then tightening the 13mm nut this gives clearance between the tensioner shoulder and the belt passing round the idler, but trying to get the tool out after releasing the tension on the belt so the pointer is over the reference hole creates the same problem there's then insufficient clearance to pull the tensioning tool out without dragging it over the belt you can get in and out no problem when the pointer is above the hole but obviously that's an over-tensioned position. The car was previously done by an alfa garage and I checked before removing the belt and to my surprise the pointer was above the hole so they must have had a similar problem. I don't understand what the marks are for on the belt itself as they don't line up with the crank and cam pulleys at TDC although a manual Ive read says they should and presumably alfa put them on for a reason.
 

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Discussion Starter #7
I also looked at the pointer position on another 156 TS that had its last belt change at an alfa garage and again the pointer is above the hole....
 

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I had an issue with a tool but it was years ago. I think I had to use emery paper or a bench grinder to dress up the peg of the tool so it fitted into the corresponding hole in the engine. I have also had some sort of issue on a very skimmed cylinder head whereby the cam on the tool was not large enough to move the tensioner far enough. I used a flat screwdriver to reduce the clearance to move the tensioner further over.

I can not make sense of the bit suggesting the belt is in the way.

If you continue to have issue, please post pictures.
 

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Discussion Starter #9
Thanks I'll take some pictures and post them tomorrow. Essentially, as the tensioner slides inwards tensioning the belt the peg hole in the crankcase has got a lot of clearance round it so the peg slips in out easily, but when the tension is off the belt, the metal shoulder on the tensioner is too close to peg hole to get the peg in to apply tension and the lack of clearance persists unless the tension is increased so the pointer is above the hole. This makes it impossible to align the pointer over the hole using the special tool. I tried tools from 3 different kits the base of one of them is much slimmer than the other 2 which didn't work at all but, even with the slimmer one if I adjusted the tension to the recommended setting the gap between the shoulder and the belt where it passes over the idler was too tight to extract the tool without damaging the belt.
 

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It really shouldn't be that tight if you have every thing loose. Have you counted the teeth on the belt you took off against the new one. CF1/2 1.6TS engines use a different (longer) length belt from CF3 1.6s. If someone has replaced the engine in your car at some point its possible they fitted an earlier engine. I've never tried to fit a shorter belt on an older engine to know if its possible but it would also explain the issue with access with the tensioning tool as the belt will be tensioning too quickly.
Note - the belt should be overtensioned when you first fit it, after replacing the cam caps and locking up all the bolts th engine should be turned through two full turns back to TDC then the tensioner pointer should be adjusted so its set over the hole.


Thanks. I'm surprised the belt fitting is that easy as I've really struggled to get it round all the pulleys the only way so far is by removing the idler putting the belt on all the other components and then carefully fitting the idler which works but I'm not happy is the right way to do it. I've moved the cam sprockets left and right in attempts to lift the belt on with no change its dead tight.
The tensioner does slide ok and I've slackened all the bolts on everything right off but Ive found it really difficult to tension the belt using the alfa tool with the peg on the end the only way I can get it into the hole on the crankcase is by pushing the tensioner pointer round with a screwdriver then tightening the 13mm nut this gives clearance between the tensioner shoulder and the belt passing round the idler, but trying to get the tool out after releasing the tension on the belt so the pointer is over the reference hole creates the same problem there's then insufficient clearance to pull the tensioning tool out without dragging it over the belt you can get in and out no problem when the pointer is above the hole but obviously that's an over-tensioned position. The car was previously done by an alfa garage and I checked before removing the belt and to my surprise the pointer was above the hole so they must have had a similar problem. I don't understand what the marks are for on the belt itself as they don't line up with the crank and cam pulleys at TDC although a manual Ive read says they should and presumably alfa put them on for a reason.
 

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Discussion Starter #11
It really shouldn't be that tight if you have every thing loose. Have you counted the teeth on the belt you took off against the new one. CF1/2 1.6TS engines use a different (longer) length belt from CF3 1.6s. If someone has replaced the engine in your car at some point its possible they fitted an earlier engine. I've never tried to fit a shorter belt on an older engine to know if its possible but it would also explain the issue with access with the tensioning tool as the belt will be tensioning too quickly.
Note - the belt should be overtensioned when you first fit it, after replacing the cam caps and locking up all the bolts th engine should be turned through two full turns back to TDC then the tensioner pointer should be adjusted so its set over the hole.
Thanks yes I agree with what you say. But the old belt had 163 teeth and I got an alfa kit 71736729 and the belt in that has an identical number as the old one. Not relevant to the difficulty in fitting the new belt but the old belt looked a lot stronger than the new alfa replacement the sides show no seams like the alfa or dayco ones either just dense black rubber. I'll get some pictures.
 

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It’s been a long time since I did my old TS belt but I remember mine was fairly tight slipping it on. Are you fitting it in correct sequence along with having cam sprocket loose so any slack opposite side to tensioner is pulled round?
Also I also seem to recall not using the Alfa tool to tension it but used a lever, as said over tension turn engine over back to TDC make sure timing is still ok then back tension off to mark. Turn over again by hand and recheck tension
 
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