Date: Wed, 12 Jan 2000 01:49:19 +0100
From: Robert Brown <>
Subject: Re: The dreaded turbo smoke? Classic 900

I can't comment on whether or not blue-white smoke would've been due to oil-clogged air filter. Bud I'd like to add my 2 cents' worth about disconnecting the ventilation hose from the tappet cover (embedded in text below) . . . best to solve the real problem behind this Emlyn Whitley wrote: > There are two occasions when I have had bluish white smoke bellowing > out of the rear end of my 900T 8v, once was intermittant and the other > non stop. The non stop event was when the turbo went -at approx. 125k > miles- and meant plumesof smoke enriched the habitat of all around > when I accelerated from standstill ie traffic lights or when at speed. > The other occasion, and this may be more relevant to your situation, > happened just after I had had the car seviced. The new air filter went > in very nicely. I bet that if you take your air filter out of its > plastic cannister you will find that it will have some oil swishing > around in the bottom of it. This oil gets there via the tube from the > cylinder head- for some reason the best place for this overflow is the > air intake. The reason for the hose is *not* to draw excess oil from the tappet cover. The idea is that blow-by gases (going past the piston rings on combustion) are vented from the crankcase through the engine block, up to the tappet cover (where camshaft sits). These gases (containing incompletely-burned hydrocarbons) are to be sucked back into the engine via the hose and air filter housing (though they will bypass the air filter). So the idea is that only gases are to go through the pipe. But if the screen in the tappet cover (look for a slot at one end of the tappet cover, viewed from the inside) is partially clogged, oil will tend to go through the pipe due to excess pressure in crankcase/tappet cover. Best way to solve the problem is to remove tappet cover, turn upside down, plug hole where gases/oil exit, pour a few ounces (or about 20 centilitres) petrol/gasoline in. Remove gasket from tappet cover edge to avoid disintegration from the petrol and be sure to avoid splashing the distributor if you leave it attached. Let it sit a while. Discard dirty petrol and repeat a few times. Clean hose between tappet cover and air filter in same way. Wipe everything dry (i.e. no petrol to be left) and refit cover. > I rerouted this pipe so that the oil now dropsout of the > bottom of the engine bay. That's the ugly way of solving the problem ;-) > Obviously it was too much for the mechanic to > clean out this cannister prior to putting in the new air filter. Cleaning out the canister in this case is kind of like rearranging the deck chairs on the Titanic. A small amount of oil in the canister is common and not usually a problem, unless it flows out to the bottom of the air filter. > The > oil was being sucked up into the engine and burnt off -hence the > blue/white plumes of smoke intermittantly bellowing out.I assume > intermittantly because it is only under hard accaleration that enough > demand- ie suction-is called for to draw this oil via the filter-which > was saturated- and into the engine.It may be that this is your problem > too. > Hope this helps! My guess is that Simon may have a turbo bearing seal problem instead. Smoke (white, I believe) will be generated, at best intermittently. Wouldn't mind hearing from Simon what the problem turned out to be. // Regards, Robert > > > On Thu, 06 Jan 2000 09:50:02 GMT, (surfsofa) > wrote: > > >Can I enlist the help of some classic 900 turbo experts please. > > > >Last night on my drive home from work I was feeling a bit racey so I > >booted my turbo once the engine had warmed up. > > > >For the first time since I got the car (it's now done 141000miles on > >the original turbo) I got smoke out of the tail pipe. As it was dark > >couldn't tell what colour. > > > >Obviously I was a bit worried. Later on the same drive I booted it > >hard to see if it would happen again and it didn't. Loads of boost > >still on tap. > > > >Is it possible that this smoking thing can happen intermittently? > >Could this be caused by : > >- car had been virtually unused for a week in cold, damp weather. > >- car had not been driven hard for a while - ie. almost no boost in > >the yellow > >- car has to do a relatively short commute daily - 7 miles each way. > > > >Of course I'll be keeping an eye on it, but could those with > >experience suggest what symptoms suggest what. ie. is it a gradual > >failure, or will it go suddenly, and can the symptoms I've offered > >cause a temporary smoking? > > > >Thanks for your help. > >-- > >surfsofa > >

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