Diesel engine noise

[pitway]

I have read on a couple of forums about adding some two stroke oil to diesel , supposedly helps lubricate  injector pumps and other internal bits of diesel engines. Other claims about improved fuel consumption and performance too.

The jury seems to be out on this, anyone do this?? think the ratio of 200:1 is the suggested mix. 

[Chancer]

Only if I run a tank of Clamc, seems a reasonable precaution given the lack of additives. Now that the price has shot up to €1.09 a litre there are not many queueing at the pump with their jerricans.

I have also been using up a jerrican of 90% petrol 10% diesel melange that I recovered after someone used the wrong pump, I dose a couple of litres to a tankfull when I remember, when I do I notice that there is very marginal increase in fuel economy.

I dont have a new generation HDI diesel but one of the last VAG engines with a mechanical diesel pump.

[crossy67]

I would be very careful tampering with the fuel in a modern diesel engine.  The fuel pumps run at very high pressures and as such need very very close tolerances, they fuel acts as a lubricant for these pumps.  Adding petrol or other oils will alter the fuels viscosity and more importantly it's lubricity and could cause premature ware/failure.  I have known many people ruin £100's or pounds worth of fuel pumps by running them out of fuel.

[pitway]

I wouldn't want to mess with the fuel on a new car that has Catalytic converters and particulate filters and the like, modern diesel engines are designed to run on new low sulphur fuels, but some of the older diesel engines like mine were not, the article that was discussed was supposedly written by Mercedes and suggested that it was beneficial in restoring the lubrication of the pump lost by the removal of the sulphur (or the part that creates sulphur when it is burnt???)

As an aside, I drive lorries for a local factory all the vehicles are Mercs actros, the slightly older one has far more power and is more economical than the newer modern one that is using an (ethenol??) additive (adblue) system, the engines are the same but the difference is quite noticeable as is the fuel consumption! in the region of 10 litres per 100km difference

[AnOther]

Whilst sticking religiously to manufacturers service schedules may be good for some for peace of mind, warranties, and resale values, in truth it's all a bit of a con. You only have to compare the schedules for a British car and its direct LHD equivalent, identical cars in almost every way but for the side the steering wheel is on, to realise that.

Take a British car which specifies oil changes at 10,000 miles, go over then whoops, there goes your warranty. The LHD car on the other hand will typically say 15,000km which is a nice round number but of course is only 9,375 miles. Logically, with the same engine as the British car, there is no reason you shouldn't take it to 16,000km or 10,000m but of course you can't for the same reason, invalidating the warranty.

For as long as I can remember I've done all my own servicing and apart from recently for cam belt changes (just can't be ar55ed) I rarely if ever go anywhere near a garage for anything. I'll do oil changes when I think it's necessary and convenient to me. All my cars have gone well into upper 100,000m territory and some into 200,000m and more, the last one was at 240,000m when I sold it and I know for a fact that it has since passed 300,000 and is still going strong on a daily commute from the UK south coast into West London so ignoring servicing schedules clearly has not had disasterous consequences there.

As far as I'm concerned then simple mileage based servicing is little more than a cash cow for the dealers and a potential warranty get out.

[Chancer]

Spot on.

As far back as the mid or even early 90's to conform with the US emissions requirements (then the most rigourous) vehicle engines had to be able to do 100000 miles without any servicing at all and still remain within emissions limits.

With the then modern oils it was no problem for diesel engines which contaminate the oil far more than petrol ones, en revanche the spark plugs in petrol engines werent up to the job, the weaker link the contact breaker points having long been superceded, the manufacturers had to create longer lasting spark plugs hence the platinum and iridium ones that are now the norm, these being more resistant to fouling on weak mixtures should have resulted in a generation of super economical ean burn engines but the commercial interests of the precious metal manufacturers put paid to that and we are now saddled with inefficient Lamda 1.0 cataytic convertor engines.

Any modern car with its oversized air, oil and fuel filters and modern oils can happily skip services without significant risk, mine is now up to 300000 miles having only had oil and filter changes loosely every 12/18 months and one one occasion over 2 years, the air filter has been changed once because it had started to degrade (the fuel economy was unchanged) it still has the original injectors, glowplugs and diesel filter, the cam belt I finally changed last year when it started to degrade leaving the OE tensioners, water pump and pulleys in place.

The brake pads have been changed a few times when they were near to the end of their life, I finally changed the discs when one cracked at 270000 miles otherwise they would have remained.

I dread to think what the cost would have been to an owner over the last 11 years if they had put their car in the garage for routine servicing plus had to pay out for all the other unnecessary repairs deemed essential by the dealers