David, Thanks for the info, and for being so frank. You don't seem to have much faith in my old Toyota. The smoke it blows is black not blue and very little oil is used between changes,not enough to justify adding oil. It has always been a smokey engine despite attention to injectors etc. The ammount of smoke varies with engine load. Keeping the revs between 2,500 and 4,000 and using a small "throttle opening" minumises it. Adjusting the smoke screw only reduces the already inadequate performance. After 350,000 km the rings are most probably worn as indicated by the vehicles tendency to creep forwards when parked on a slope and restrained only by engine braking, low-range first. The following may sound like an add but should be familiar. The Hilux is the most reliable,economical ,practicle vehicle I have ever owned. (Lets not mention lack of comfort or character). Running costs so far (fuel, oil,grease,servicing,parts, repairs,tyres,registration,insurance etc) 11.9c/km. Fuel consumption 10L/100km. Last set of front tyres lasted 81,000km,rears still going. Brakes relined 259,000 and 440,000. Exhaust system replaced 259,000 and currently in good condition. Clutch,gearbox,transfere case, front & rear diffs all origional. Used daily, often carries load, current odometer reading 540,000km. End of ad. and no I wouldn't sell it for quids. Lets consider the operation of 4 stroke diesel engines. unlike their petrol equivalent, diesels have no variable restriction in the inlet tract (butterfly in carb or air inlet for fuel injection). Oil burning in the petrol 4 stroke is usually associated with worn rings/bore or faulty/worn valve guides or valve stem seals. It is most obvious when the air pressure inside the cylinder is substantially less than that in the sump. Such conditions occur when the throttle is suddenly closed at high rpm or after prolonged idling. The diesel takes a full gulp of air at each intake stroke regardless of "throttle setting" so the difference in pressure between cylinder and sump at induction is not so great especially with positive crankcase ventilation. The increased pressure and temperature of the diesel engine combustion would probably burn the lubricating oil more effectively producing black smoke from an enriched mixture. Ring blowby also feeds oil fumes to the intake. The original engine in the Hilux was treated to some spray start (ether) by an unsympathetic unknowing moron ( me) when it refused to start one winter. (Glow plugs coated with soot don't warm the preignition chambers too well). End result broken rings. 50,000 km later things started to get interesting. The engine began to run on the crankcase fumes. Usually this would occur as the "throttle" was backed off just as a hill was crested. The engine would suddenly roar and rattle whilst belching black smoke from the exhaust. Very disconcerting for those following. Not only would the engine run on the fumes but it would accelerate. ( can't understand why when the ignition was occuring well before injection point).The only way to calm it down was to apply the brakes firmly until normal running resumed, don't know the theory behind this. Braking was also disconcerting for those following. The only time I have ever witnessed this in another vehicle was when a Diamond Rio was delivering a load of coal to the factory where I worked. This was a spectacular sight and sound punctuated by the driver and his helper abandoning ship.
Regards, Paul. Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Please do NOT send "unsubscribe" messages to the list address. To unsubscribe, send an email to: [EMAIL PROTECTED] Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
