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Omega Help Area => Omega General Help => Topic started by: Varche on 19 May 2009, 18:18:06

Title: Cambelt change - second problem!
Post by: Varche on 19 May 2009, 18:18:06
Bit more concerned now. I have put the belt on correctly and everything loked OK. Did 360 degree clockwise turn of camshaft (720 of crank) timing marks on bank 3 and 4 have moved about one tooth to the right of the notches on the double C tool. Try and adjust but can't seem to make any headway using the lower idler.

Are you only supposed to adjust by turning anticlockwise?
Is it possible to "strip" the internal mechanism on the idler? I tighten up the central bolt then turn but the bolt comes loose again. maybe I haven't got it tight enough in the first place. Grrrrr

varche
Title: Re: Cambelt change - second problem!
Post by: Marks DTM Calib on 19 May 2009, 18:40:33
Sounds like you have the cambelt fitted incorrectly.

The DVD gives info on how to sort it out
Title: Re: Cambelt change - second problem!
Post by: Darth Loo-knee on 19 May 2009, 18:47:01
If you are one tooth to the right on Cams 3 & 4 you but ok on banks 1 & 2, put the lock into 1 & 2, slacken the idler at the bottom so this will release tension on banks 3 & 4, then bring Cams 3 & 4 bank into the correct position with the Top idler inbetween 2 & 3.
Once you have got them back put in the lock for Cams 3 & 4 and start again.
Hope this helps :y
Title: Re: Cambelt change - second problem!
Post by: Marks DTM Calib on 19 May 2009, 18:59:32
Quote
If you are one tooth to the right on Cams 3 & 4 you but ok on banks 1 & 2, put the lock into 1 & 2, slacken the idler at the bottom so this will release tension on banks 3 & 4, then bring Cams 3 & 4 bank into the correct position with the Top idler inbetween 2 & 3.
Once you have got them back put in the lock for Cams 3 & 4 and start again.
Hope this helps :y

No need to start again, just re-thread the belt over 3-4.
Title: Re: Cambelt change - second problem!
Post by: Varche on 19 May 2009, 19:01:21
Yes Ok will try that. I am convinced that it was all OK before first turn of the cams. I suppose as there is a lot of slack it is vaguely possible that I have let the belt jump over 3 and 4.

And my question about adjusting the idler using the 30 m ring spanner is it only ever anticlockwise?

Title: Re: Cambelt change - second problem!
Post by: Marks DTM Calib on 19 May 2009, 19:02:44
Anticlockwise...

the bottom idler should start at about 3 Oclock and ends up at about 12 Oclock and the upper starts at 12 Oclock and ends up at about 9 Oclock
Title: Re: Cambelt change - second problem!
Post by: Varche on 19 May 2009, 19:38:41
Quite disconsolate now.

First here are the facts.

The belt has now done one complete rotation clockwise only. However the marks on the belt aren't underneath the bottom crank pulleyas they were to start off with but about five teeth further on i.e. past where they started ditto approx on both bnks of cams.

bank 3 and 4 is virtually correct apart from being maybe as little as 1/16th inch out.

Bank 1 and 2 is very nearly a tooth out.

Have torqued the central idler bolts up correctly and then tried turning the 30mm nut anticlockwise. On the lower one it ends up loose and the central bolt needs torqueing up again.

On the upper one it is all so tight that I darent try and adjust it for fear of breaking it.

If I have tatered one or both of the tensioners can they be bought seperately?

Any thoughts please? :-[

Title: Re: Cambelt change - second problem!
Post by: Varche on 19 May 2009, 19:46:01
The top idler started off in the correct position and is now at 5.30p.m and the bottom started off in the correct position and is now at 12 noon.
Title: Re: Cambelt change - second problem!
Post by: jonathanh on 19 May 2009, 19:46:52
o.k. here are few thoughts

1. you have not done any damage (yet) so take a breather and go back to it later.  In my experience, rushing a job is a sure fire way to cause a problem.

2. don't worry about the alignment marks on the belt, worry about the alignment with the crank lock and the timing gauge.

3. I sounds like you need to adjust bank 1 & 2.  you need to use the ring spanner on the centre tensioner, holding it still whilst loosening the retaining bolt.  Helps if you have three hands here I find.  

Adjust the centre tensioner with the ring spanner to get the alignment on banks 1 & 2, then tighten the retaining bolt.  Do it up so it holds- not super tight or torque it, you can do that later

turn over the engin by hand to help the belt settle and check again

post up some piccies and we can help further
Title: Re: Cambelt change - second problem!
Post by: Marks DTM Calib on 19 May 2009, 19:48:16
Quote
Quite disconsolate now.

First here are the facts.

The belt has now done one complete rotation clockwise only. However the marks on the belt aren't underneath the bottom crank pulleyas they were to start off with but about five teeth further on i.e. past where they started ditto approx on both bnks of cams.

bank 3 and 4 is virtually correct apart from being maybe as little as 1/16th inch out.

Bank 1 and 2 is very nearly a tooth out.

Have torqued the central idler bolts up correctly and then tried turning the 30mm nut anticlockwise. On the lower one it ends up loose and the central bolt needs torqueing up again.

On the upper one it is all so tight that I darent try and adjust it for fear of breaking it.

If I have tatered one or both of the tensioners can they be bought seperately?

Any thoughts please? :-[



Sounds spot on for a pre-adjusted setup.

So set the lower right idler to get the 3-4 cams aligned with the gauge and then set the upper idler to get the 1-2 cams aligned
Title: Re: Cambelt change - second problem!
Post by: Varche on 19 May 2009, 19:54:06
Jonathon. I agree. Sadly haven't got a third hand to help and wielding the 30 mm and the other tool isn't easy.

One other plus point is that I marked the top of the crank pulley with a dab of white snopake so I know I am getting the right spot without having to use the mirror.  
Title: Re: Cambelt change - second problem!
Post by: Omegatoy on 19 May 2009, 20:03:18
Damn !! you should have shouted i would have come over to give a hand!!!
but tomorrow one of the dogs in in for an operation, thursday i am required to sort a car, and friday we go shopping!! lets see how you get on if no joy will pop over poss sat? have to ask the boss first tho!!! ;D
Title: Re: Cambelt change - second problem!
Post by: jonathanh on 19 May 2009, 20:40:23
I was thinking the same.  o.k. so I'm three hours flying time away but i don't need much of an excuse to visit andalucia, having a weakness for manzanilla and sherry (La Ina).  Next time you need a hand, I may just pop over....
Title: Re: Cambelt change - second problem!
Post by: Varche on 19 May 2009, 20:44:59
Stopped for the night too dark, too tired.

I'll start afresh tomorrow with some pictures and a fresh mind or two.

I have had a look at the old tensioners (and belt none of which were in bad nick for the four year rule) and concluded I haven't stripped anything so shouldn't need any more parts.

cheers guys

Title: Re: Cambelt change - second problem!
Post by: JamesV6CDX on 19 May 2009, 22:23:32
Remember on initial fitting (if no marks present on the belt) the extra slack goes tensioner side, not idler side...
Title: Re: Cambelt change - second problem!
Post by: Varche on 19 May 2009, 22:51:47
James - It is a contitech kit with all the markings. Thought it would give me a better chance. Even the backing plate is the same as mine and I have used the small headed long bolt as specified for the lower idler. the top one comes already attached to the back plate.

To be quite honest there wasn't any real slack on fitting I found it quite hard (for my useless hands anyway) to fit it all. I started from the crank using proper locking tool, and did cams 1 2 3 and 4 in that order then fitted lower idler to hold it all in place.

Just trying to get a photo bucket account. Might be useful tomorrow onwards.  :)

varche
Title: Re: Cambelt change - second problem!
Post by: Darth Loo-knee on 19 May 2009, 22:56:58
I personally find it easier to go the opposite way 4,3,2,1 :y