Reflecting on some of the topics which have passed through this excellent forum I wonder what has gone wrong with this industry.
The petrol question for one - we've all got this the wrong way round. Surely the simple fact is that a maker who supplies vehicles which fail to operate properly on fuel supplied to the British Standard has got to mend his ways or suffer the consequences. It's simply unacceptable to be presented with vehicles whose engineers have failed to do their homework. I've never seen any hint of this issue raised abroad. It would be of value to learn which makers supply "delicate" engines and which supply more robust units.
The cambelt question for another. For heaven's sake, if a volume maker can't get right a simple thing like an idler why are they still in business? When you look at the machinery that was and is developed for Defence, would the Government accept engines that couldn't stay out of the workshop or that showed red lights when leaving the base. In its heyday the internal combustion engine was fearsomely intricate, think of a 48 cylinder radial aircraft unit, and had to be maintained in primitive conditions. They can get it right if they want to.
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Hear hear. My comment on the ridiculousness of a machine which is designed not to start after you have moved it into your drive and back again because the catalyser isn't up to the job is another.
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Hi Growler,
I agree totally with your thoughts on this non-start question, but have to pick you up one one thing. It ain't anything to do with the Cat. The Cat is just an apendage in the exhaust system that alters the chemical content of the gasses passing through it. It is not connected to the management system, and the only way the system even knows it is there is on very late cars with an additional Lambda Sensor aft of the Cat. Otherwise you could take the Cat off and it would make no difference to the actual starting / running. Very, very occasionally you do get a non-start due to the Cat being totally blocked, but this can happen to an ordinary silencer too.
The starting problem that has been discussed recently is do with small valve diameters, very rich mixtures on cold start, carbon build-up on short trips, and pussy-foot driving. As you say, the damn thing should be able to cope with all of this, but they sometimes don't.We can only advise owners what to do to lessen the risk of problems.
Regards for now, Adam
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Adam
I would appreciate clarification on this point. I thought that the problem with driving the car off the drive or out of the garage and then stopping was with unburnt fuel damaging the cat, you seem to be taking a different view. And why do most people seem to say that this is not a problem with diesels?
Sorry if I'm being thick!
Rob
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Rob,
Sure, it is not GOOD for the Cat, but the more immediate + common problem is that such short use often creates a non/difficult start when the car is next needed, basically due to it having flooded itself. Personally, I find Cats are much hardier than we were initially led to believe - did a car yesterday that had been run with a totally open-circuit plug lead (ie total misfire) fro two weeks, but after sorting that and giving it 5 miles at 60mph the emissions were fine.
HTH, Adam
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Thanks Adam, I appreciate the explanation.
By the way, a colleaugue of yours up here in Cumbria has helped keep my old Cavalier and several other second cars on the road with regular servicing , I felt quite guilty when we bought an 18 month old diesel Sharan last year!
Rob S
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TGW
I'm afraid your reference to the MoD is really not valid. Vehicles that they have designed for them are not built to the same agenda as those we buy from car showrooms, and they put a lot of work into reliability and maintainability programmes using their own trained mechanics and maintenance facilities.
We buy cars that are known as COTS - Commercial Off The Shelf. So does the MoD, with vehicles such as Land Rovers. They suffer the same failures as you and I in this area.
I agree that there is no justification for shoddy engineering. Cam belt sagas are a disgrace, but fit the manufacturer's agenda perfectly. They are cheap to manufacture and build as part of a new vehicle. As long as the punter pays to take the vehicle to an "authorised" garage and obey all the rules of the warranty and service shedules for an umlimited period of time, then he should be OK. The manufacturer has passed the reliability problem over to the customer.
I think we are moving towards a "throw away" car culture. They will get down to a value where the cost and complexity of repairs (particularly electronics and software) is much more than the car is worth. Why should the manufacturer care? He needs to keep selling new cars.
The losers will be the people who have to look out of their windows at the dumped hulks in the streets, because disposal costs will be higher too.
Ian
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Adam,
Another request for clarification.
I was under the impression that removing a cat on some vehicles (e.g. Audi 80 circa 1989) required changing the engine management system slightly because of the reduced back pressure.
Regards,
LAS FC
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LASFC
Not just back pressure. The mixture requirements for a cat are different to ensure it fully coverts the CO, HC's etc. A cat equipped car always runs at stochiometric conditions (lambda = 1). Without a cat leaner mixtures can be used under some operating conditions, with the consequent economy gains.
regards
John
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Thanks Adam, I appreciate the clarification and will now be wiser round the bar!
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T.G.
Ahem.
>When you look at the machinery that was and is developed for Defence, would the Government accept engines that couldn't stay out of the workshop or that showed red lights when leaving the base.<
Heard about the tanks in Afghanistan that broke down after a few miles because the Government would not pay for the conversion required? SA 80 rifles anyone?
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TGW,
As I understand it, fuel standards are different in Europe and in the USA. Lubricity enhancers and detergents in fuel to maintain the petrol injection system do not have a BS.
Cost engineering in the car industry has been a way of life since mass production. The emphasis on aesthetics is highly appeaing to most people and to the manufacturers advantage (minimum developement costs). The cam belt, in my view, is out of date togeather with the low design cost idlers that tension it.
I wonder if folk would be happy with a "No Frills" cabin and body shape, but instead a high quality well designed power unit, transmission and running gear for the same price?
Regards,
Julian L
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I see that even modern engines, both petrol and diesel, still use cam belts. Surely it would make far more sense for all engines to use the more robust chains. My previous car, a 94 Astra 1.7d had a can belt, which I had changed, along with the tensioner, every 35K miles. My current car, a 2000 Vectra DI, uses a timing chain, which I assume will not need changing and is a more robust design. Anyone care to comment on the pros and cons of cam belts versus timing chains?
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And what about gear drive? After the disastrous VF 750 produced by Honda in the mid-eighties it redesigned the engine to come up with the VFR 750 which is now widely recognised as an exceptionally reliable motor, it certainly saved Hondas reputation in the bike world. I think that the VW VR6 is also gear driven, does this mean it is only possible with V engines (the VFR is a V4)?
Rob S
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This is the main reason why, when I replaced my Vectra 1.6 (5 idlers/tensioners in 5 years), I went for a Zafira diesel. I have reached the stage where, given my own experience and the accounts of others, I simply have no faith in GM's petrol units and won't consider another one for a long time to come.
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I'm tempted to defend Vauxhall petrol engines................................but I don't want upset Roland and friends again! (ref. High Mileage Bores thread)
Rob S
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Well, if the BS standard ignores items which will are necessary for the proper functioning of an engine perhaps it's time that the BSI had a serious conversation with the industry.
If standards are indeed higher abroad, the least that the government can do for its expensive fuel is to ensure that its quality is amongst the best. After all, at the end of the day the consumer is keeping all of these organisations in business.
Transparency is the best policy. Would it not be a good idea if HJ would advise us of those engines which, in his extensive experience, are adversely affected by the cheapest petrol commonly available and, especially, those which are not?
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IMHO, it does not make sense to design an engine with a component which has an acknowledged limited and unpredictable life and make no provision for the condition of that item to be able to be inspected.
I have been told that visual inspection of a cambelt in situ is not practicable or sufficient, so I would not deem that type of transmission to be suitable in those circumstances and manufacturers should look at alternatives.
After all, cam belts are not that much different to (say) camshafts. You do not expect to strip an engine down every 50,000 miles and replace the camshaft "just in case". Why should you have to do that to the belt?
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"I wonder if folk would be happy with a "No Frills" cabin and body shape, but instead a high quality well designed power unit, transmission and running gear for the same price?"
Sounds like a Mk2 Golf to me....
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