Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Terbs on 13 March 2015, 16:00:45

Title: Cambelt failure
Post by: Terbs on 13 March 2015, 16:00:45
Hi all
Disaster !!!!!!! What does the engine sound like if the cambelt has broken. Car has been on the drive, being checked out for MOT Tuesday, and I went to start it and it just whired. Initially, it made a weak attempt to start. Nothing sounds bangy or clonky. Have not done it again in case it mucks something up. I am going to try to get a friend of mine to come round to have a look (mechanic).
Does this sound cambelt....its within its time/mileage. :'(
Title: Re: Cambelt failure
Post by: Marks DTM Calib on 13 March 2015, 16:08:26
They spin over fast with little or no compression
Title: Re: Cambelt failure
Post by: Terbs on 13 March 2015, 16:14:18
Yes Mark...that seems to be a good description. I see there are two small bolts on the front of the cover. If these are removed, is it possible to get in at the belt to see.
And...as the engine did not run...do you think there would be damage inside. :y
Title: Re: Cambelt failure
Post by: Nick W on 13 March 2015, 16:29:26
Did you start it and turn it off very quickly the last time it ran? If so you have probably flooded it. That's a straightforward 'fix', pull the fuel pump fuse(or the relay)and crank it over with the throttle open for as long as the battery is strong. Refit the fuse and crank it normally until it starts. If it's really bad then you'll need to remove and dry the plugs - warming them up on the gas stove or with a small blowtorch is the best method.


I can't remember if any of the cams are visible through the oil filler; if they are then look through the filler while someone else turns it over for a couple of seconds. If the cams are moving then the belt is probably OK. This will save you any dismantling to check. Do this before you do the first suggestion!!!


Broken cambelts sound very distinctive on most engines, but there are exceptions.
Title: Re: Cambelt failure
Post by: Terbs on 13 March 2015, 16:39:57
Hi Nick...
When I went to start it, I turned the key, it initially fired, then went into Whirring. I stopped immediately. Then tried again but it whirred, as Mark describes. but I only did this for a couple of seconds at most. :y
The last time it ran properly was yesterday, when I put it on the drive for a wash and valet. It behaved normally. :y
Title: Re: Cambelt failure
Post by: Nick W on 13 March 2015, 16:48:56
Hi Nick...
When I went to start it, I turned the key, it initially fired, then went into Whirring. I stopped immediately. Then tried again but it whirred, as Mark describes. but I only did this for a couple of seconds at most. :y
The last time it ran properly was yesterday, when I put it on the drive for a wash and valet. It behaved normally. :y


So you started it, moved it and turned it off? That's the classic cause of flooding the next time you go to start it. I see this all the time at work, and the 'cure' is what I described. It can take several goes for it to start, and on cars where removing the plugs is easy is the best solution.
Title: Re: Cambelt failure
Post by: Terbs on 13 March 2015, 17:02:12
Thanks, mate...I shall do all tests required
Grateful :y
Title: Re: Cambelt failure
Post by: Field Marshal Dr. Opti on 13 March 2015, 17:09:25
Hi Nick...
When I went to start it, I turned the key, it initially fired, then went into Whirring. I stopped immediately. Then tried again but it whirred, as Mark describes. but I only did this for a couple of seconds at most. :y
The last time it ran properly was yesterday, when I put it on the drive for a wash and valet. It behaved normally. :y


So you started it, moved it and turned it off? That's the classic cause of flooding the next time you go to start it. I see this all the time at work, and the 'cure' is what I described. It can take several goes for it to start, and on cars where removing the plugs is easy is the best solution.




Certainly is for an RX8.

.......but for an Omega. ??? ???
Title: Re: Cambelt failure
Post by: Nick W on 13 March 2015, 17:27:04
RX-8s are the worst, but it's a possibility on all FI petrol engines. The more cylinders they have the harder they are to start, and long plug change intervals are often the culprit(in my opinion). It's one of the reasons why I change mine every other oilchange.


Some of the worst offenders are: 16v Micras, Jag V8s(next to impossible to start without heating the plugs, and the driver's side require removing part of the inlet manifold), poorly serviced BMW 6s, Mk1 Focus.


The best cure is to get into the habit of not starting and immediately turning it off; if you have to move it around, go around the block, or leave it running while you move the others/get the hose etc out.
Title: Re: Cambelt failure
Post by: 05omegav6 on 13 March 2015, 17:45:17
Fingers crossed that it's summat daft :-\
Title: Re: Cambelt failure
Post by: Terbs on 13 March 2015, 17:52:35
Fingers crossed that it's summat daft :-\

I got fingers, legs, willy and everything else crossed Al. :(

My fiend is coming round, so I am not going to touch anything till he gets here.
Belt is two and a half years old on 23000 miles. Conti belt
Title: Re: Cambelt failure
Post by: Kevin Wood on 13 March 2015, 18:45:28
Unlikely to be the belt, I'd say. Often if they're badly flooded the bores get washed so it seems to be turning over with reduced compression too.

Charge the battery fully, Foot on the floor, crank it for 5 second periods, resting between, then foot off the gas and try and start it.

If it does start, keep the revs up for 10 seconds or so, then take it round the block, as said.
Title: Re: Cambelt failure
Post by: Terbs on 13 March 2015, 18:49:26
Result........flooded.
Nick....champion mate.

Friend came round, tried the keys gingerly then said..'Thats not belt, it attempted to fire' albeit almost non existant...so he gave it the gun and away it went.
And on top of that, he said he would take it in and test it...he is an MOT tester !!!!!!!!!!!
So relieved ..........so spare cash can still be put towards number 3 ;D :y
Title: Re: Cambelt failure
Post by: 05omegav6 on 13 March 2015, 18:50:16
Get that man a pint :y
Title: Re: Cambelt failure
Post by: The Sheriff on 13 March 2015, 18:50:38
Nice one, Nick :y :y
Title: Re: Cambelt failure
Post by: Andy B on 13 March 2015, 18:53:06
A nice cheap fix!

As Nick says above, they're easily flooded when started & moved to shuffle cars about ..... apparently Christmas is a busy time for recovery firms
Title: Re: Cambelt failure
Post by: Sir Tigger KC on 13 March 2015, 18:54:25
Happy Days!  :y
Title: Re: Cambelt failure
Post by: Toledodude1973 on 13 March 2015, 19:50:04
Another Omega saved by OOF  ....terrific site :y
Title: Re: Cambelt failure
Post by: Nick W on 13 March 2015, 19:50:24
Result........flooded.
Nick....champion mate.

Friend came round, tried the keys gingerly then said..'Thats not belt, it attempted to fire' albeit almost non existant...so he gave it the gun and away it went.




That's the clue, and is when I ask about what's actually happened since it was last used. I only bother with the 'flood clear' procedure if the pump fuse/relay/cut-off switch aren't obvious.


Micras are good for this, because if you're quick when it catches, you can stick the fuse back in and look smug knowledgeable.


I'm glad it was nothing serious. And you might want to consider 6 new plugs ASAP.
Title: Re: Cambelt failure
Post by: Terbs on 13 March 2015, 20:08:55
When I see you, either at Wycombe or in Kent, I'll get you a drink or a breakfast.  :y

Just been out to try it and it started sweet as a nut as normal.
What causes them to flood like that. I can't recall it ever doing that before, either of them come to that. ???
Title: Re: Cambelt failure
Post by: Nick W on 13 March 2015, 20:16:55
The cold start on an FI engine works by adding extra fuel, unlike a carb which reduces the airflow.
If you turn it off before the cold start has started to decay, it's still running quite rich. Then, if it doesn't catch the first time it turns over, you end up with wet plugs and your problem. This is why I distrust the long plug change intervals/infrequent servicing, as these seem to be the worst culprits.


So, ensure the ignition system is up to scratch, and don't turn it off  if it has only run for a few seconds.
Title: Re: Cambelt failure
Post by: Terbs on 13 March 2015, 20:21:21
Thanks for the explanation, Nick....grateful :y
Goes to show...you learn something every day ;)
Title: Re: Cambelt failure
Post by: Steve B on 13 March 2015, 20:21:58
The cold start on an FI engine works by adding extra fuel, unlike a carb which reduces the airflow.
If you turn it off before the cold start has started to decay, it's still running quite rich. Then, if it doesn't catch the first time it turns over, you end up with wet plugs and your problem. This is why I distrust the long plug change intervals/infrequent servicing, as these seem to be the worst culprits.


So, ensure the ignition system is up to scratch, and don't turn it off  if it has only run for a few seconds.
What a shorter period before new plugs you mean  :-\