Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Entwood on 18 September 2011, 22:05:18

Title: Cam Timing
Post by: Entwood on 18 September 2011, 22:05:18
As some may have read the Pink One came down last week to change my cambelt etc for me ..

http://www.omegaowners.com/forum/YaBB.pl?num=1316121161

It was at 38700 miles and 3 years 8 months since changed as parrt of the deal when I bought the car. Never been touched since then. All the old bits were genuine GM parts, and it looked like the water pump had been done as well .. so a half-decent job I thought ...  until Daz pointed out that the passenger bank was 1/4 tooth out and the drivers bank about 1 1/4 teeth out ... When he did the job he took great care to ensure both sides were spot on ......

Now in the nearly 4 years I've never had cause to call the beast "underpowered" .. it went well and pulled the 'van without effort .. an fuel consumption was, I thought, quite reasonable for 3.2 litres in a 1.7 tonne vehicle driven quite sportily at times.

I've been away at a reunion this weekend .. done around 400 miles since he did the job and the difference is really noticeable .... engine is more responsive and quicker off the mark and fuel consumption is better by about 6% !!!

So, not only do you need to know what you are doing, the proper timing tools are essential to get the best performance from the engine. Makes those who say you can time the V6 without the tools even more wrong IMHO ... I did not expect it to make as big a difference .

Once again ... thanks DAZ   :y :y :y :y
Title: Re: Cam Timing
Post by: Andy B on 18 September 2011, 22:42:16
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... Makes those who say you can time the V6 without the tools even more wrong IMHO ...  ....

It's always been said that it was at best, a good guess.  :y :y :y But apparently the tensioner also make a difference to the timing ..............  ::) ::)
Title: Re: Cam Timing
Post by: Darth Loo-knee on 19 September 2011, 09:17:57
Sounds like a Good Result there Nige  :y

I know when Mrs. loo-knee's estate timing was out we got 27mpg on a run. After I had put it right it did 35mpg on the way down to Devon packed up for holidays :y

It is suprising because I did a Cambelt the other day which was a new engine from Vauxhall, again never been touched since it came from the factory and yet again the timing was out........


Andy as far as I see the tensioner just keeps the belt tight.  :y
Title: Re: Cam Timing
Post by: Andy B on 19 September 2011, 09:36:57
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Andy as far as I see the tensioner just keeps the belt tight.  :y

You & I know that, but a certain admin & I had a long winded 'debate' about the subject  ::) ::) ::)
Title: Re: Cam Timing
Post by: aaronjb on 19 September 2011, 10:14:18
I really must check mine - I get ~26-27 on a run in the 3.2, and as I found out this morning, struggled to out-drag a Toyota Carina (Corona?)  :-?
Title: Re: Cam Timing
Post by: joff on 19 September 2011, 10:23:06
Just done a 600 mile trip and at 70mph ish i was getting 32mpg from the 3.2 Elite is this about right. :-/
Title: Re: Cam Timing
Post by: Marks DTM Calib on 19 September 2011, 10:30:52
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Andy as far as I see the tensioner just keeps the belt tight.  :y

You & I know that, but a certain admin & I had a long winded 'debate' about the subject  ::) ::) ::)

What I have stated is that you cant set the tension correctly when the cam timing is out (as the cam lobe positions affect the belt tension on the sloppy side)

At no point have I stated that the tensioner affects cam timing.
Title: Re: Cam Timing
Post by: aaronjb on 19 September 2011, 10:35:43
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Just done a 600 mile trip and at 70mph ish i was getting 32mpg from the 3.2 Elite is this about right. :-/

Well it's better than I get  ;)
Title: Re: Cam Timing
Post by: Andy B on 19 September 2011, 11:22:09
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Andy as far as I see the tensioner just keeps the belt tight.  :y

You & I know that, but a certain admin & I had a long winded 'debate' about the subject  ::) ::) ::)

What I have stated is that you cant set the tension correctly when the cam timing is out (as the cam lobe positions affect the belt tension on the sloppy side)

At no point have I stated that the tensioner affects cam timing.

I was refering to A N Other boyish admin  :y :y :y  ;D ;D ;D
Title: Re: Cam Timing
Post by: TheBoy on 19 September 2011, 11:59:41
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Andy as far as I see the tensioner just keeps the belt tight.  :y

You & I know that, but a certain admin & I had a long winded 'debate' about the subject  ::) ::) ::)

What I have stated is that you cant set the tension correctly when the cam timing is out (as the cam lobe positions affect the belt tension on the sloppy side)

At no point have I stated that the tensioner affects cam timing.

I was refering to A N Other boyish admin  :y :y :y  ;D ;D ;D
As MDTM says, you can't set the tension correctly if the cam timing is incorrectly adjusted. Thats why its the last step in the renewal procedure.
Title: Re: Cam Timing
Post by: Darth Loo-knee on 19 September 2011, 12:08:00
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Just done a 600 mile trip and at 70mph ish i was getting 32mpg from the 3.2 Elite is this about right. :-/

I think that sounds a good MPG return mate :y  3.2's seem to be more thirsty in my opinion than the 3.0   :)
Title: Re: Cam Timing
Post by: Field Marshal Dr. Opti on 19 September 2011, 12:14:20
My belt was changed by VX so I'm well and truly Donald Ducked. :-/
Title: Re: Cam Timing
Post by: Darth Loo-knee on 19 September 2011, 12:25:39
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My belt was changed by VX so I'm well and truly Donald Ducked. :-/

Where I think Vauxhall's problem is, (again in my opinion just so I don't get stoned to death ;D) they put the belt on using the locking kit, get the timimg right then torque everything, then put it back together.
Anyone who has done any Cambelts should know that when you have put on the belt, making sure the timing is spot on so tighten everything, then turn the car over by hand that the timing is slightly out when checked again. So should then be fine tuned. This is where Vauxhall go wrong...... In my opinion as they do not turn the engine over by hand a few turns, then re check, turn over a few times then check  ;)
Title: Re: Cam Timing
Post by: Darth Loo-knee on 19 September 2011, 12:28:56
9 out of 10 people who say their car cambelt has been done by Vauxhall, I would feel safe enough to put money on it being out.
It sounds stupid I know but true  :-?
Title: Re: Cam Timing
Post by: Andy B on 19 September 2011, 12:58:50
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As MDTM says, you can't set the tension correctly if the cam timing is incorrectly adjusted. Thats why its the last step in the renewal procedure.

A little nibble there I think ......  ::)
Title: Re: Cam Timing
Post by: robmac on 19 September 2011, 13:13:13
having spent about half a day getting my cambelt timed correctly amid much cursing and head scratching and re doing it untill i was happy i can confirm it feels much livelier than it was before and fuel economy is much better, returning 38 mpg on a run of 50 miles on dual carriageways at 70 to 80 mph. with the climate control on auto too so its deffiniately worth getting it done properly imo.
Title: Re: Cam Timing
Post by: johnnycboy on 19 September 2011, 17:54:01
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Just done a 600 mile trip and at 70mph ish i was getting 32mpg from the 3.2 Elite is this about right. :-/

I think that sounds a good MPG return mate :y  3.2's seem to be more thirsty in my opinion than the 3.0   :)


I get bugger all near that at best I get 22MPG :o
Title: Re: Cam Timing
Post by: dbug on 19 September 2011, 21:40:42
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Just done a 600 mile trip and at 70mph ish i was getting 32mpg from the 3.2 Elite is this about right. :-/

I think that sounds a good MPG return mate :y  3.2's seem to be more thirsty in my opinion than the 3.0   :)


I get bugger all near that at best I get 22MPG :o

Bl**dy hell mate - thats krap  but you talking town driving, motorway driving or combination?
Title: Re: Cam Timing
Post by: feeutfo on 19 September 2011, 23:05:40
Iirc Nige, I did hint it felt a bit under powered. Although at the time presumed the single pipe mid section exhaust might be the culprit.  :-/

Is yours a fixed bottom roller? Actually that's I silly question of both banks where out. Later models have fixed bottom roller, so only bank 1 can vary.  :y
Title: Re: Cam Timing
Post by: The Red Baron on 20 September 2011, 01:12:43
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Just done a 600 mile trip and at 70mph ish i was getting 32mpg from the 3.2 Elite is this about right. :-/

I think that sounds a good MPG return mate :y  3.2's seem to be more thirsty in my opinion than the 3.0   :)


I get bugger all near that at best I get 22MPG :o

Bl**dy hell mate - thats krap  but you talking town driving, motorway driving or combination?
something to do with your right foot john.  ::)
Title: Re: Cam Timing
Post by: Kevin Wood on 20 September 2011, 10:10:21
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Iirc Nige, I did hint it felt a bit under powered. Although at the time presumed the single pipe mid section exhaust might be the culprit.  :-/

Is yours a fixed bottom roller? Actually that's I silly question of both banks where out. Later models have fixed bottom roller, so only bank 1 can vary.  :y

It's still pretty easy to get bank 2 a tooth out. If you don't bother to turn the engine over 720 degrees at least once you can't be sure all the slack has been taken out by the tensioner and that you are seeing the true timing.