Blue smoke from AAZ

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Wilma
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Blue smoke from AAZ

Post by Wilma »

Hope someone can help. AAZ engine in Wedge. Ever since I have had her (two years) there has been blue smoke on start up from cold after standing for or at least 16 hours. Engine missfires at the same time. All of this clears in about 30 seconds and then everything is normal - good performance, no oil is used, no problems. Started again within the 16 hours and no smoke, normal start. Yesterday, however, severe clouds of blue smoke on starting, chronic missfire, though engine ran on tickover. Try to accelerate and rear disappeared in smoke. Missfire so bad that driving was impossible. Then smoke cleared and could drive gently, but as soon as accelerate the missfire was back and the smoke. Given another three or four mionutes and all cleared and back to normal. No problems from then on. This morning same problem, but not so bad - smoke and missfire cleared in about a minute the back to normal. Tickover fine, no smoke. On first occasion had not been started for three days, this morning it had been left overnight, so it seems that the longer it is left the worse the problem.What is it? Oil draining down somewhere? Turbo seals? Valve seals? unlikely I would have thought. Its done 7800 on a new head. Turbo has done about 15000.
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CovKid
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Re: Blue smoke from AAZ

Post by CovKid »

Others with more experience of this engine will come along I'm sure but I guess all diesels are similar. I had a MIDI van with the Isuzu lump in and it was rings in that case. I had to get up at 5am and start it if I wanted it for 9 otherwise the whole street would come out with the cloud of smoke. As a starter though, try leaving the glowplugs (preheat) on for longer or do the cycle twice before starting her, see if that improves things. Might just be one or two dodgy glow plugs?
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syncroandy
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Re: Blue smoke from AAZ

Post by syncroandy »

It's not going to fix itself and the only way of finding the cause is head off surely ? Broken ring perhaps ? The turbo is always a suspect but if its that new then it should be OK. Is the inlet manifold full of oil ? I don't see how dud glow plugs could cause these symptoms, blue smoke=oil.
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Re: Blue smoke from AAZ

Post by Simon Baxter »

Crank pulley has come loose.
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Wilma
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Re: Blue smoke from AAZ

Post by Wilma »

Thanks so far fellahs. Further investigation shows blown oil in engine bay, nearside and some on engine below valve cover. A small amount of oil used - about quarter pint. No oil, burnt or otherwise on or around turbo. Air filter clean, though some blown oil on the case. Top of engine and offside completely clean. Small amount of oil below crank pulley. Starting the engine with the bay open shows no smoke or oil apparent around the engine itself the smoke only comes out of the exhaust pipe. Still starts instantly so I don't think it can be glow plugs, and performance is unchanged once the oil has burnt off on starting. Have checked pulley, its tight and I think a loose one would affect the performance. Don't really want to start dismantling without some ideas as to where to start, but may have to do that. All contributions gratefully received!
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CovKid
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Re: Blue smoke from AAZ

Post by CovKid »

Is it just possible you've sprung a leak and its burning on the exhaust?
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