[urq] Burning huge amounts of oil after turbo rebuild and new EM after 6 months of use.
a.sigal at bluewin.ch
Thu Aug 30 15:17:27 EDT 2007
- Well Maurits, Im afraid no smoke on idle doesn't tell much, although
good colour plugs with small amount of dry deposit shows that oil is not
burned in the cylinders. However, If you want to establish what is at
fault, and how good the rings and guide seals are, you have to perform
the tests at relevant revs, and with engine fully warm. Providing that
the head has the mileage to suspect seals and guides, then do it like this:
-Leave engine fully warm to sit for ten minutes or so, then start the
car and rev it to 4K, then keep it on 2,5K or so for 10 sec or so.. If
a puff of blue smoke comes out and then stops, it means that guide seals
-You can test for rings condition by reving the engine several times to
high revs and se if you get the smoke on the overrun, but with turbo
suspect, you should use different method, which is by feeling with your
hand how much pressure is coming from the crankcase. Same as you've
done, disconnect the hose from the igloo end and block the igloo side.
Bring the engine to 3K, keep it on revs and feel with your palm how much
pressure comes out. The amount of gas that comes out of there is the
amount of compression that leaks through the rings, so less blow means
better rings condition, usually very good on 5 cyl.
-Since the oil consumption was average before turbo swap, everything
points to turbo, which is a little strange, and since it is a PITA job,
you should look into the oil drainage issue, since obstruction there
would create pressure at turbo shaft seals. Apart from that, not much
more you can do but change the turbo, which could still be under
guarantee; Is it?
Maurits Jonkergouw wrote:
>Ado, thanks for the info. Just returned from the lab :-) and the results of
>the crankcase ventilation test returned negative I guess: no smoke at idle
>but just a little water from the not oily exhaust. I removed the iglo hose
>at the valve housing (T-split) like you said and capped it. Curiously put my
>finger on the now open valve housing end and felt vacuum was drawn, but
>still no smoke.
>Took out the small plastic one-way valve inside the valve housing to the IM
>and also checked the valve housing itself for oil: they where just a little
>wet and the valve functioned well, I guess it's perfectly OK then.
>Plugs are not wet at all and have the perfect colour, there are some
>deposits, but considering how old they are (18759 km), that's normal I
>Valve cover seal and other oil seals are also absolutely dry.
>Although I'm not sure what should have happened when disconnecting the
>breather hose in either case, but my guess it's burning oil at the hot side
>turbine seal and not in the cylinders and means it has to be rebuild again,
>1986 quattro GV
>1982 Coupe GL DD
>----- Original Message -----
>From: "Ado Sigal" <a.sigal at bluewin.ch>
>To: "Maurits Jonkergouw" <urq at moregraphics.nl>
>Cc: "Audifans" <urq at audifans.com>
>Sent: Thursday, August 30, 2007 4:33 AM
>Subject: Re: [urq] Burning huge amounts of oil after turbo rebuild and new
>EM after 6 months of use.
>>That's huge amount of oil burned, and if it started after rebuild, it must
>>be to do with work done.
>>- First establish where the oil is burned. If in cylinders, the plugs
>>would be oily with lots of deposit, and if plugs are fine, then the oil is
>>burned through hot side turbine seal. The exhaust will be oily in both
>>- If oil is burned in the cylinders, and it wasn't before the work, it
>>could be that crankcase pressure is created, and is pushing the oil
>>through valve guides and oil viper rings into cylinders. To make sure that
>>there is no pressure going to crankcase, simply disconnect the crankcase
>>breather hose that goes from igloo to valve cover. Cap the igloo end end,
>>and test for smoke. Might also check the other breather to IM connection,
>>which is one way valve with metered orifice. Clean it up and make sure it
>>works correctly. (If excessive crankcase pressure was created, as
>>indication, the engine would be wet arround valve cover and other related
>>-The routing of crankcase ventilation is the difference between GV and WR,
>>not the exhaust.
>>- Change of oil line plays no importance, if the leak on the old one
>>didn't leave the engine without oil at any time.
>>-Dialynx EM also controls wastegate through the bottom WG chamber, which
>>is connected via same metal/high temp hose as the old one was. This only
>>plays part how well WG is controlled, but plays no part in the oil issue.
>>Well, test and let us know which one it is.
>>Maurits Jonkergouw wrote:
>>>Hmmm, oil consumption is getting worse each week since april this year...
>>>Did a small test, perhaps you could comment on this:
>>>Idle for 10 minutes > accelerate fast to 5000 RPM > huge cloud of smoke
>>>from the exhaust.
>>>Guys, what does this mean? I'm very worried about this new 1 liter oil per
>>>500 km thing.
>>>Also checked the 'michelin hose' for oil by disconnecting it at the iglo
>>>and putting down a rubber flex hose all the way down to the turbo intake
>>>and pulled it out to see if there was some oil on it, which is not.
>>>Perhaps not the best way to check but didn't want to remove the tray below
>>>the bumper and disconnect the hose directly from the turbo intake...
>>>Things that might be of importance: one of the oil cooler lines has been
>>>replaced, not sure it was exit or supply though. Turbo is a rebuild and
>>>valves are readjusted to spec. My old exhaust manifold was cracked and is
>>>replaced with Dialynx EM, all at the same time around december 2006.
>>>Before the EM swap there was a hose present from the iglo to the
>>>wastegate, but is now removed. The header on the iglo is capped off, the
>>>header on the wastegate is not capped. To my knowlidge the wastegate is
>>>now controlled by turbo pressure.
>>>Another thing that I still don't understand: this is a GV engine, not WR,
>>>and the only difference is some of the exhaust is routed back and reburned
>>>or something like that to reduce CO. I've red that the original WR engine
>>>used exhaust pressure to control boost level, I'm not sure if the original
>>>GV uses the same technique and if the 'new' Dialynx method controlling
>>>boost without exhaust pressure? (not sure how exactly boost level is
>>>controlled withe the Dialynx EM), interfers with the original GV method to
>>>reduce CO, in other words: this is bad or good.
>>>Any comment or insights/thoughts are welcome, thanks.
>>>1986 quattro GV
>>>1982 Coupe GL DD
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