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[Andy H]

Getting a bit confused here i think, so with the belt on in its current set up turn the crank until its 60 degrees before TDC which is where on a clock face? Where does the crank mark need to be on a clock face and do i lock it or will it just stop there?

10 o clock as you look at it

That was my first answer because that is correct if you are looking at the timing tool- BUT the timing mark is on the bottom of the crank pulley so 4 O'Clock is the winning answer.

[terry paget]

As the belt is ON at the moment should i rotate clockwise until i get to 4 o clock

ALWAYS!

Why not anticlockwise, through 60 degrees rather than 300 degrees? Come to that, would it not be as safe 60 degrees after TDC as before it?

[Nick W]

As the belt is ON at the moment should i rotate clockwise until i get to 4 o clock

Hi



ALWAYS!

Why not anticlockwise, through 60 degrees rather than 300 degrees? Come to that, would it not be as safe 60 degrees after TDC as before it?

It's bad practice to rotate it anti-clockwise because the tensioners don't work that way, and you could loosen the crank bolt. Of course both those points are moot in this case, you're never going to accidentally loosen the bolt, but why take the chance?

[gbh]

All stop again which is annoying,came to fitting the pulleys crank and a/c torqued to 20nm after searching on here then the water pump which seems to be somewhere between 8-12nm anyway at 8nm 2 of them didn't feel that great like they might sheer so i removed and will replace all 3 i think maybe clean the threads as well.Best place for bolts and do you use Loctite? Then which torque? Unfortunately on the dvd he never tightens the bolts only by hand maybe he forgot!!!

[Andy H]

All stop again which is annoying,came to fitting the pulleys crank and a/c torqued to 20nm after searching on here then the water pump which seems to be somewhere between 8-12nm anyway at 8nm 2 of them didn't feel that great like they might sheer so i removed and will replace all 3 i think maybe clean the threads as well.Best place for bolts and do you use Loctite? Then which torque? Unfortunately on the dvd he never tightens the bolts only by hand maybe he forgot!!!

According to the Haynes book the bolts should be 'angle tightened' and used only once. I haven't angle tightened or replaced mine - so far I have just tightened them to 8Nm with a dab of Loctite for luck.

You are right to be cautious, Kevin Wood recently had the water pump pulley make a bid for freedom on his car (I assume he was driving his Omega and not his LSIS)

[gbh]

Which Loctite?

[terry paget]

As the belt is ON at the moment should i rotate clockwise until i get to 4 o clock

Hi



ALWAYS!

Why not anticlockwise, through 60 degrees rather than 300 degrees? Come to that, would it not be as safe 60 degrees after TDC as before it?

It's bad practice to rotate it anti-clockwise because the tensioners don't work that way, and you could loosen the crank bolt. Of course both those points are moot in this case, you're never going to accidentally loosen the bolt, but why take the chance?

Fair comment. I first did this job on a clattering engine (2 teeth out) and wanted to turn it the minimum angle. I wondered if there were any cams on the engine with steep back slopes that would resent/resist being turned the wrong way. I have two on print presses.

[Andy B]

Which Loctite?

Take your pick  https://www.google.co.uk/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=loctite%20threadlocker
there are different grades for different applications, but in this case, any one of them will be good enough

[terry paget]

All stop again which is annoying,came to fitting the pulleys crank and a/c torqued to 20nm after searching on here then the water pump which seems to be somewhere between 8-12nm anyway at 8nm 2 of them didn't feel that great like they might sheer so i removed and will replace all 3 i think maybe clean the threads as well.Best place for bolts and do you use Loctite? Then which torque? Unfortunately on the dvd he never tightens the bolts only by hand maybe he forgot!!!

According to the Haynes book the bolts should be 'angle tightened' and used only once. I haven't angle tightened or replaced mine - so far I have just tightened them to 8Nm with a dab of Loctite for luck.

You are right to be cautious, Kevin Wood recently had the water pump pulley make a bid for freedom on his car (I assume he was driving his Omega and not his LSIS)

I have found the Haynes instruction, as you say 8Nm then tighten 30 degess/30 degrees. All I have ever done is do them up finger tight, put on the belt, then nipped them up as I think fit, knowing the belt will slip if I get carried away.

[gbh]

I just contacted Vauxhall who say there are 2 types only difference is length 13mm and 15mm both about a £1 each but the 15mm are  minimum order of 10.Mine i would say are 15mm but 13mm should be ok with Loctite what do you think?

[Kevin Wood]

Loctite is essential on the water pump pully bolts as they are so physically small that they can't take a lot of torque. They are probably worth  replacing every couple of belt changes, TBH. Mine had been off or a running repair shortly after the last cam belt change and probably didn't get replaced with enough, or any, Loctite.

2 of them had come undone and dropped out. The third one sheared during a spirited climb up a steep dual carriageway. Luckily, I didn't lose the pulley itself and nothing went into the cam belt. The water pump immediately blew its' seal, probably due to instant boiling of coolant in the block as the pressure and flow dropped (like I said, I was driving "spiritedly").

[Nick W]

I just contacted Vauxhall who say there are 2 types only difference is length 13mm and 15mm both about a £1 each but the 15mm are  minimum order of 10.Mine i would say are 15mm but 13mm should be ok with Loctite what do you think?

Use the longer bolts with a washer.
But these are standard M6 bolts that cost pennies. You could buy a box of several hundred and have enough change from that tenner for lunch. Buying them from Vauxhall is stupid.

[terry paget]

Loctite is essential on the water pump pully bolts as they are so physically small that they can't take a lot of torque. They are probably worth  replacing every couple of belt changes, TBH. Mine had been off or a running repair shortly after the last cam belt change and probably didn't get replaced with enough, or any, Loctite.

2 of them had come undone and dropped out. The third one sheared during a spirited climb up a steep dual carriageway. Luckily, I didn't lose the pulley itself and nothing went into the cam belt. The water pump immediately blew its' seal, probably due to instant boiling of coolant in the block as the pressure and flow dropped (like I said, I was driving "spiritedly").

Thank you gentlemen. Next time I change a cam belt I shall change my procedure in several ways. I see Haynes recommends new bolts and angle tightening for the  power steering pulley too, but not for the crankshaft pulley. I should be nervous of angle tightening 30:30 those small water pump pulley bolts. I was taught that angle tightened bolts should never be re-usued, as they have been stretched on first use, but on this forum this rule is widely ignored.
 

[Nick W]

Thank you gentlemen. Next time I change a cam belt I shall change my procedure in several ways. I see Haynes recommends new bolts and angle tightening for the  power steering pulley too, but not for the crankshaft pulley. I should be nervous of angle tightening 30:30 those small water pump pulley bolts. I was taught that angle tightened bolts should never be re-usued, as they have been stretched on first use, but on this forum this rule is widely ignored.

ANY bolt that has been tightened has stretched; that's how they work! Angle tightening is specified because it gives more consistent results with simpler equipment than a torque wrench, in blind holes. Where a nut and bolt are used in critical applications (on a conrod big end for instance), you actually measure the bolt stretch with a micrometer.


As for reusing them, 3 M6 bolts to attach a waterpump pulley is already more clamping than is actually necessary to do the job.even an average quality bolt is far stronger than its matching female thread. You can prove that for yourself: put an M6 nut in a vice and tighten a bolt into it with an ordinary 1/4" drive ratchet.

[Andy H]

Loctite is essential on the water pump pully bolts as they are so physically small that they can't take a lot of torque. They are probably worth  replacing every couple of belt changes, TBH. Mine had been off or a running repair shortly after the last cam belt change and probably didn't get replaced with enough, or any, Loctite.

2 of them had come undone and dropped out. The third one sheared during a spirited climb up a steep dual carriageway. Luckily, I didn't lose the pulley itself and nothing went into the cam belt. The water pump immediately blew its' seal, probably due to instant boiling of coolant in the block as the pressure and flow dropped (like I said, I was driving "spiritedly").

Thank you gentlemen. Next time I change a cam belt I shall change my procedure in several ways. I see Haynes recommends new bolts and angle tightening for the  power steering pulley too, but not for the crankshaft pulley. I should be nervous of angle tightening 30:30 those small water pump pulley bolts. I was taught that angle tightened bolts should never be re-usued, as they have been stretched beyond their elastic limit on first use, but on this forum this rule is widely ignored.

So called 'stretch bolts' are manufactured from steel which has a certain amount of 'spring'. If you stop tightening a bolt before the spring runs out then it will return to it's original length if you loosen it again. If you carry on tightening a bolt once the spring has run out then you have reached the 'elastic limit' and the stretch (or some of it) is permanent. The bolt material is selected so that the clamping force is known and is not dependent on the amount of lubrication on the bolt threads or the calibration of a torque wrench.

Using stretch bolts for the cylinder head allows manufacturers to build engines that don't need to have the head bolts re-torqued after 500 miles. I struggle to see what VX were trying to achieve though through angle tightening 6mm water pump pulley bolts