Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[dave.h]

Sorry to post again but I’m having major issues changing the timing belt on my V6.

I have all the cams and crank lined up and locked and am following the video.

Problem is that the new belt doesn’t seem to fit.

I line the double line up with the crank mark and wedge it and work Up the cam 1 and 2 side, exactly as in the video.

The belt goes on cams 1 and 2 and the marks align, it goes around the idler and on to cams 3 and 4  but the lines are out and the belt just won’t go around the idler. I took it off and with the belt on the idler won’t go back in as the belt is too tight.

Anybody got any words of wisdom I can use?

The kit is for the car and the back plate with the tensioner on is the same code as the one that came off.

It’s doing my bloody head in!!

Cheers in advance

A frustrated man!

[biggriffin]

Don't bother with the lines, once you turn it over by hand they all go to cock, they are just there to make it easier to line the pulleys up,.  If you have the locks in, and the cam wheels line up with the marks on the back plate, and your bottom pulley hits the marks, and it's tensioned, then it's fine.  Last belt I fitted had so many marks it looked like a rainbow, and none of them lined up.

[TheBoy]

Don't pay masses of attention to the belt markings, they are probably wrong.

The belt should be tight everywhere.

Does the DVD say do it clockwise?  I must look at it again, as I've always done it anticlockwise 

[biggriffin]

Don't pay masses of attention to the belt markings, they are probably wrong.

The belt should be tight everywhere.

Does the DVD say do it clockwise?  I must look at it again, as I've always done it anticlockwise 

Me to, fitted from bottom up, anti-clock,,4321. Down

[dave.h]

Don't bother with the lines, once you turn it over by hand they all go to cock, they are just there to make it easier to line the pulleys up,.  If you have the locks in, and the cam wheels line up with the marks on the back plate, and your bottom pulley hits the marks, and it's tensioned, then it's fine.  Last belt I fitted had so many marks it looked like a rainbow, and none of them lined up.

That's good to know - but the belt just will not fit.  When it is on the crank, tensioner cams and top idler, it won't fit over the lower idler - it is tight and it I take the idler off like in the video, the belt won't let the bolt line up to replace the idler.  It's like the belt is 2 inches too short.

[Enceladus]

As I recall the earliest cars that haven't got the modified tensioner assy are anti-clockwise, (-->MY '96?), looking from the front. Later cars with the modified tensioner go clockwise. The modified tensioner can be fitted to the earlier cars.

[TheBoy]

What is the backplate ID (stamped in the webbing of rear of backplate) on both new and old?

[robson]

Have you compared the length of the old belt and the new one.

[STEMO]

Have you compared the length of the old belt and the new one.

That's far, far too easy 

[dave.h]

Have you compared the length of the old belt and the new one.

Yeah - same size! See below for further woe.....

[dave.h]

What is the backplate ID (stamped in the webbing of rear of backplate) on both new and old?

I am about to shoot myself.  Got the belt on finally, arrows in the right direction, marks lined up.  Followed the video and pre set the idlers as told, set the tension as in the video.

Came to turn the motor over by hand to do the rest of the checks and …………..the fkin belt slipped.

I guess now I have to take it all off again, set the cams up (as they are now out of line) starting with No1...then do it all over again...…..

I hate myself, I used to be good at this stuff, get an incurable illness and bang, all that stops and I can't even do a timing belt anymore.

Is there anything special I need to do to get everything in alignment now?

[dave.h]

What is the backplate ID (stamped in the webbing of rear of backplate) on both new and old?

Both say 01

[Doctor Gollum]

Wind the crank back 60°, then reset the cams and lock them, then reset the crank to tdc and refit the belt. Use a mirror and a wedge to locate and secure the belt on the run from the crank to the tensioner

[dave.h]

Wind the crank back 60°, then reset the cams and lock them, then reset the crank to tdc and refit the belt. Use a mirror and a wedge to locate and secure the belt on the run from the crank to the tensioner

Thank you very much, I appreciate the help.

This has to be the most helpful forum I have ever been a member of. Good job too as I seem to have turned into Frank Spencer.

[Doctor Gollum]

That was from memory, but you get the gist

[Nick W]

If the belt is the same and you have the crank and cams locked correctly, and the belt won't fit then you must have one or more of the tensioners misaligned. That could be because you've turned them to the wrong part of the eccentric - this is probably what made the belt slip when you turned the engine through - or that you're mixing the different backing plates/adjustable/non-adjustable tensioners.


Layout everything you took off, and compare to what you have now.

[Enceladus]

MY '97 onwards the tensioner roller was modified. The later type has a deeper outer flange. If you try and install the belt anti-clockwise on one of these then there probably won't be enough slack to get a new belt onto the tensioner. This is probably made worse if you haven't fully backed off the upper and lower eccentrics and worse again if you are using a fixed (ie non-eccentric) bottom roller.

Hence the GM mounting procedure for the belt changed to clockwise installation. IE. Crankshaft -> Tensioner roller > Cam1 --> Cam2 --> Upper idler --> Cam3 --> Cam4 --> Lower idler - Crankshaft. Since the newer tensioner design was a retrofit I would have thought that there are no cars left with the old design. Your car would have the new type. What make and part number is your kit?

Back-off the upper and lower eccentrics, as per Nick W above, and install the belt clockwise.

[Doctor Gollum]

You naively assume that all the dealers changed the pulleys 

They didn't, hence the halving of the interval on anything with this engine

[Enceladus]

You naively assume that all the dealers changed the pulleys 

They didn't, hence the halving of the interval on anything with this engine

Irrelevant. My comments are related to comparing old and new parts.

What matters now is what kit he is actually trying to install? Unless it's very old stock, it will have a new type tensioner and the belt needs to installed clockwise.

[TheBoy]

On a 6 cylinder engine, 60 degrees off TDC (before or after) is the position when all pistons are halfway down the cylinders, thus "safe".

So Doctor Gollums suggestion is sound. Get the pistons "safe", then get the cams 1 and 2 in the right place (2nd set of hands might be useful, and a 2nd T45 tool), get the lock in place, then repeat for cams 3 and 4.  Then get crank back to where it was to TDC.  Then refit belt.

[biggriffin]

On a 6 cylinder engine, 60 degrees off TDC (before or after) is the position when all pistons are halfway down the cylinders, thus "safe".

So Doctor Gollums suggestion is sound. Get the pistons "safe", then get the cams 1 and 2 in the right place (2nd set of hands might be useful, and a 2nd T45 tool), get the lock in place, then repeat for cams 3 and 4.  Then get crank back to where it was to TDC.  Then refit belt.

  ^^^^^^^

[dave.h]

Well, thanks to everyone's help I managed to get it all sorted out yesterday.

I had one of the idle rollers mis set as was suggested.

After I got everything realigned I fed the belt back on clockwise and made sure it was a good tight fit into the teeth as I went.  Then I removed the passenger side roller, set it at it's lowest position and boom, belt on.

Set the tension, then sorted the timing out after a rotation and managed to get everything exactly aligned on the gauge.

Car now running like a swiss watch thanks to those that commented on this post - thank yo very much to you all.