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Discussion Starter #1
Just finished a cambelt and water pump change on my gtv using the so called correct method.But i really cant see why the old method of marking everything up including the belt would cause any issues.There are plenty of similar engines with keyed cam pullys that have no problem with belt tension.surely once the cam pullys are in the correct position from the factory the timing is good .If i had to change just the belt and rollers again i would just mark it all up and save a hole lot of time.
 

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Did you slacken the 4 cam pulleys and watch them all pull around on their tapers when you tensioned the belt?
 
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More modern Fiat/Alfa engines use to have some teeth sprocket play around the cam key, you loosen the sprocket bolts and turn the sprockets as far as they goes clockwise and then you put on the timing belt anticlockwise, tension the timing belt and fasten the sprocket bolts, turn engine over two revolutions by hand and and check that timing is OK and if the timing is right your are done, I can't see how you would manage to
do this without cam locks and get it right.
 

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Discussion Starter #4
More modern Fiat/Alfa engines use to have some teeth sprocket play around the cam key, you loosen the sprocket bolts and turn the sprockets as far as they goes clockwise and then you put on the timing belt anticlockwise, tension the timing belt and fasten the sprocket bolts, turn engine over two revolutions by hand and and check that timing is OK and if the timing is right your are done, I can't see how you would manage to
do this without cam locks and get it right.
The cambelt on my car had its first cambelt change done by just marking up the sprockets and belt.This was all visible when taking it apart this time.The car always ran great and on this change where i used the cam locks to hold cams they all fitted correctly.I really cant see a problem in marking up belt and pullys so that everything goes back on the way it came off.I did remove cam pullys this time to remove the rear cam cover to make it easier to remove the water pump.There are plenty of quad cams engines with longer belts that have no problem with fixed cam pullys and these tension the belt fine.
 

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Ive changed many cambelts over the years on various different cars this way....the so called wrong way:thumbup:
 

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My last GTV had not long before I bought it had the cambelt done at a non Alfa garage using I suspect the incorrect method.

The engine was very slightly lumpy at tickover and was down on power compared to what it should have been, but otherwise ran ok.

Unless you have driven a healthy 3.0 to compare you may never have noticed the difference.

if you are going to the effort to change a V6 belt you may as well do it properly, as it does make a difference to the engines power output.
 

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Discussion Starter #7
i just dont see the difference between this engine and many others except it has no timing marks.
 

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Please tell me how you can be sure that timing belt tension is correct on other places than between crankshaft pulley and bank1 exhaust cam pulley if you tighten the tensioner with fixed camshaft pulleys and how you preserve engine timing when engine starts to rotate.
 

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Discussion Starter #9
You transfer timing marks from old belt to new belt.You can then line them up with marks on the pully.Zip tie belt to the pully on the marks.You can also clamp or zip tie pairs of sprockets together.it means that each tooth on the belt is where it was.Ive used this method on subaru and vauxhall v6 with no problems.
 

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always a good debate on this one... the issue with just paint marking things up and replacing the belt is that over time the old belt will stretch a little, so it may be 1 or 2 mm longer between given points, for example crank pulley to cam pulley. Automatic tensioners take this up, as does incorrect adjustment!
So if you just replace the belt using old marks, yes, its almost impossible to be a tooth out, yes it will run OK.. but you have no way of knowing if its actually 100% correct. A lot of engines don't have vernier set ups, and work "OK",, Alfa tend to do things right and fit verniers. The only way to be 100% correct is follow the factory processes, slacken verniers, fitting locking tools and adjusting as instructed.
Just my 2 pence worth, i have 30 years on the spanners, every day is a school day, i have learnt that manufactures that design and built engines tend to know more about them than me..

willi, I have seen the belts that you mention, the ones with printed marks on them to align to sprockets. a lot of french cars use them. that works as the new belt is the correct length so pullys are correct in relation to each other
 

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Discussion Starter #11
Hey its all good.Worst part of the job anyway is taking out alan bolts on cam covers without rounding them off.Now that would be a pain.
 

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gggrrr rounded allen bolts are a nightmare..
i tend to grind my 6mm allen key socket down a bit when it gets a bit worn,..my local snap on man wont change them if they snap!
so much for the life time warranty..
 

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Discussion Starter #13
gggrrr rounded allen bolts are a nightmare..
i tend to grind my 6mm allen key socket down a bit when it gets a bit worn,..my local snap on man wont change them if they snap!
so much for the life time warranty..
The top cambelt roller was so tight i managed to round if off .Lucky my stud extractor just fitted onto it and i could get it out.Took alot of force though.Putting the car back together again was a pleasure.On to the next job.
 
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