PaulN Posted November 22, 2010 Share Posted November 22, 2010 My Disco (‘96 300tdi 80k) is still smoking and it’s starting to bug! There’s no smoke on normal running and no ill effect on performance or economy (all relative) so I’ve pretty well ignored it up to now but boy does she smoke in the morning!! Checked a few things out to try and narrow it down a bit...... Only smokes from cold and then after a nights standing to get cold - but not, it appears, after a 200 mile run! First thing it’s like the SAS are on manoeuvres for the 1st 100 metres or so and then it’s gone - no smoke at all until next day. No smoke on revving or overrun when warm. No loss of performance or economy (39 mpg) No loss of oil Removed EGR valve long time ago Recently cleaned Cyclone breather, inlet manifold, intercooler and pipes (intercooler was clean) though there was dripping oil from cyclone to turbo inlet pipe when disconnected and left hanging, before it was cleaned. Checked again now and it’s just got a film from oil from vapour - which is probably normal. No wear on turbo vanes or spindle that I can feel. No oil in turbo that I could feel(at least on what I call the cold inlet side) Have not yet got compression tests yet as no uneven running or drop in perf or econ or smoke while driving. So what can the blasted cause be? Worn valve guides? - but there’s no smoke when warm - not when revved or on overrun. Worn rings? - but no crankcase puffing out through oil filler and no smoke except first 100 metres. Good even idle and excelaration - no smoke. Head gasket gone? - but no oil in water, no loss of coolant no problems running or power loss or puffing at oil filler. Worn turbo seals? - possibly! Might there be a dribble over night which is whistled through and being burnt as she gets warm? Can’t be on the cold inlet side because there is no accumulation inside interooler pipes now that she’s been cleaned. Is it possible to leak into exhaust side, pool and then be vaporised over 1st 100m or so with the dribble not big enough to notice when normal running? Can oil seep into bores overnight? - may be but there’s no smoke at start up - only after 15 seconds or so. SO it appears to be something to do with oil in something that gets hot after 20 seconds but only lasts for 100 metres but lots of it (Appears white behind in mirror and persists unlike water vapour) Is there some form of (mechanical) enrichment at start up that may have gone wrong? She even passes MOT smoke test provided it’s thrashed beforehand! Starts well and runs well but I would like to lose the SAS! AAaarrgghh! Place your bets please....... Quote Link to comment Share on other sites More sharing options...
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