Mayolives Posted October 16, 2008 Share Posted October 16, 2008 My track car has a two year old turbo engine with 2380 all track miles on the clock. I'm blowing whitest smoke only on deceleration. No smoke on start up or acceleration. Compression ranges from 148 to 143 on all six. Oil consumption is slight using only 1/4 quart at a recent three day track event, which is normal consumption since build. Turbo is a GT35-R and I run 18# boost at maximum. Also, I'm using Electromotive Tech3R fuel and engine management with all their bells and whistles except the cold start fuel enrichment part. So where is the smoke coming from? I'm getting smoke in the cabin that burns my eyes. Turbo oil seal? Any thoughts would be appreciated. Quote Link to comment Share on other sites More sharing options...
jt1 Posted October 17, 2008 Share Posted October 17, 2008 Bong? :biggrin: jt Quote Link to comment Share on other sites More sharing options...
Nismopowered Posted October 17, 2008 Share Posted October 17, 2008 I thought it was bump! But anyways no clue. White is coolant, something under vacuum? When decel vacuum is high. Maybee sucking it in somewhere? Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted October 17, 2008 Share Posted October 17, 2008 Make certain that you are not burning brake fluid. That would be bad. Keep an eye on the water levels as well. Quote Link to comment Share on other sites More sharing options...
Mayolives Posted October 17, 2008 Author Share Posted October 17, 2008 cygnusx1...............I do use some water due to radiator (S&R) being a little undersized. I have always pushed water into my oversized catch can located under the spoiler. I don't' think the smoke is from coolant because it seams to lay in the air and not dissipate quickly like water vapor normally does. Also, I'm using Wilwood brake master and clutch cylinders without a brake booster so the smoke can't be from brake fluid. Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 17, 2008 Share Posted October 17, 2008 1/4 a quart over a three-day track event? That's not oil consumption. I'd get your ventilation system fixed to eliminste the fumes, and live with the slight puff of smoke. They will do that under hard use, you may be carrying oil into the intake under drop throttle or pushing it into the intake tract through the PCV under boost , and then when you decel it all makes it's way into the cylinders instead of laying in the inlet tract to the turbo. A catch can/mist eliminator on the block PCV vent before it goes to the suction line of the turbo might alleviate it. But from the sounds of your consumption, it's nothing to worry about. The fumes are an exhaust leak, and you need to fix that, and get your car properly ventilated. I'd not worry about the puffs of smoke, personally. My 260 will use less than that in 3000 miles of high speed interstate cruising. It will use almost a quart in the same time driving on back roads and twisties. And I can use 1/2 a quart during the MSA Event Weekend. But I've no fumes... Visible smoke puffs out back, but no fumes in the cabin. Quote Link to comment Share on other sites More sharing options...
Mayolives Posted October 17, 2008 Author Share Posted October 17, 2008 Tony D quote "1/4 a quart over a three-day track event? That's not oil consumption." Yes, I'm not concerned about the amount of oil being consumed. I know that's normal. Perhaps I should have said more about the visible smoke. It's more than a puff. It now is more like a cloud. Enough to cause a black flag last weekend because the corner workers thought that I might be putting oil on the track. They did allow me to run after I assured them that I wasn't leaking any oil. I have a catch breather system plumbed with a -6 line from the valve cover to a can with small top breather/filter that sets on the fire wall. I have another one plumbed with a -10 coming from the driver's side of the block to a can with small top filter/breather. The one from the valve cover had about an inch of blow-by oil in it but not nearly full. The lower can was empty. Tony, you refered to an "oil mist eliminator on the block PCV vent before it goes to the suction line of the turbo" What is that? Please tell me more. Thanks, Tom. Quote Link to comment Share on other sites More sharing options...
rags Posted October 17, 2008 Share Posted October 17, 2008 I went through this a few years ago and addressed everything that could cause it with the exception of the turbo because the turbo was new. Yep, it was the turbo. Pretty easily detected too once I stopped being stubborn. Drop the downpipe and look inside the hot side with a flashlight. If the seal is leaking you will see oil residue in there. Mine started out the same as yours but got progressively worse over time. I'd try to drop the downpipe after a decel when it smokes. It will be hard to do because it's gonna be hot as hell but will be the best way to tell. Joe Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted October 17, 2008 Share Posted October 17, 2008 I think the L series have a tendency to puke oil out of the crankcase vent during hard use. My PCV valve has kind of a loose fit into the underside of the intake manifold and the threads constantly drip oil. This tells me that the PCV valve is passing a fair amount of oil from the block vent into the intake. I stuffed a "wire mesh ball" (homemade crumpled chicken wire fence) inside the rubber tube between the block vent and PCV valve to try to "condense out" some of the oil that was traveling up the pipe. It helped a little. My intercooler pipes are bone dry inside. My valve cover vent is open to atmosphere. In your case. You have an oil catch can (or do you not?), so It must be either valve seals or turbo seal if it's only under decel. Quote Link to comment Share on other sites More sharing options...
jgkurz Posted October 17, 2008 Share Posted October 17, 2008 During a recent track day my turbo L28 would billow smoke after a HARD downshift and sharp left turn. The turn may have nothing to to with it. Strangely the smoke came out a few seconds after the downshift and happened to be while I was in the turn. If I downshifted to say a peak RPM of 4K there would be no smoke on the same turn. My engine is practically new and doesn't burn any oil or smoke at any other time. I attribute the smoke to high vacuum pulling oil from either the valve cover or the PCV. Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted October 17, 2008 Share Posted October 17, 2008 Yup, it was probably oil coming up the PCV valve and the left hander spilling the oil into the intake runners. Quote Link to comment Share on other sites More sharing options...
jgkurz Posted October 17, 2008 Share Posted October 17, 2008 Yup, it was probably oil coming up the PCV valve and the left hander spilling the oil into the intake runners. HBZ member "hughdogz" uses a PCV oil separating tank that would solve this. Take a look at the below picture of Hugh's engine. You can just see the hose going the the tank next to the master cylinder. Maybe he'll chime in and give us more details. BTW, Hugh's engine is even more beautiful in person then it looks in the picture. Quote Link to comment Share on other sites More sharing options...
TrumpetRhapsody Posted October 17, 2008 Share Posted October 17, 2008 Would there be ill effects to putting the PCV vacuum on the valve cover, and venting the block side? Seems like the valve cover has some measure of protection to stop oil from getting to the vent, so running it "backwards" might prevent oil from getting sucked in. I think the crankcase vacuum benefits would stay the same, but correct me if i'm wrong. I have mine setup this way, only because of hosing limitations, and it seems to work fine, with no noticeable oil in the system. Quote Link to comment Share on other sites More sharing options...
hughdogz Posted October 17, 2008 Share Posted October 17, 2008 I appreciate the kind words, John. The way I have it set up is going from the engine block breather => hose => Catch can => Hose => PCV in the intake manifold. It catches some really nasty "blow-by" oil, but I still see some collecting in the return line. This says to me that it isn't catching all the catch can can. I wonder if I mounted it lower, gravity would keep more of the oil in the can...if the vacuum is high enough, I don't think it would matter too much. I've never taken apart my Cusco catch-can. I wonder if it has some sort of baffle inside, like an air-water separator for a shop air compressor. I think some kind of stainless gauze might trap the oil better too. HBZ member "hughdogz" uses a PCV oil separating tank that would solve this. Take a look at the below picture of Hugh's engine. You can just see the hose going the the tank next to the master cylinder. Maybe he'll chime in and give us more details. BTW, Hugh's engine is even more beautiful in person then it looks in the picture. [ATTACH]9849[/ATTACH] Quote Link to comment Share on other sites More sharing options...
Soundmasterg Posted October 17, 2008 Share Posted October 17, 2008 This says to me that it isn't catching all the catch can can. Haha...thats funny. I like your setup Hugh. Greg Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted October 18, 2008 Share Posted October 18, 2008 just some info that may or may not apply here....smoke on accelleration only generally indicates ring seal problems, on decelleration only, it tends to indicate valve seals, or worn valve guides Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 18, 2008 Share Posted October 18, 2008 I think Hughdog has described the system I was referring to well. Drop throttle like Grumpy mentions is usually something vacuum related, mine did the same thing a JGK's did, drop throttle, then after accelerating away mosquito abated for a second, but only after travelling a short distance. Kind of like a delayed reaction. Oil control is difficult. Make sure the turbo oil return line is free and clear to prevent it from backing up...if you get high-G oil slosh in a corner making the return back up, it can puke oil into the exhaust past the seals. VW's have pretty large volume oil separation cans to let any puke over settle out. I would make sure there is adequate negative pressure in the crankcase when the PCV is operating, and that none is building up under acceleration. If you build crankcase pressure to a high enough level, it can force oil past the valve seals, and up against the oil control ring and then when you drop throttle it looks as though you have bad seals or rings, when in reality you either needed better breather capacity, or some more volume in the system to cope with the pressurization. There is a reason the valve cover is vented before the turbo, and the PCV to the manifold---it insures that the lowest pressure (highest vacuum) point available is available to evacuate the pressures in the crankcase at all times. Putting a K&N into the housing gives horsepower by lessening the restriction...but can also reduce on-boost scavenging efficiency of the PCV system at the same time. Under boost, the source for 'make up air' is piston ring blowby. Under drop throttle and coast, the fresh air for the PCV is made up through the intake tract connection. Putting volume in either place to allow for separation of oil mists and pukeover will help keep it from getting to the combusion chamber. Really, with as little consumption as you are getting, it tends to point to more the restricted turbo return or something forcing the oil to back up and push past the turbine oil seals. And full circle, high enough crankcase pressure through excess blowby or inadequate venting of the crankcase can cause the turbo to start leaking oil past the seals, same as a physical obstruction of the drainback line. Good Luck! Quote Link to comment Share on other sites More sharing options...
proxlamus© Posted October 19, 2008 Share Posted October 19, 2008 i had the SAME problem.. I had to improve on the PCV system a bit.. but that solved all of my problems! Quote Link to comment Share on other sites More sharing options...
Mayolives Posted October 19, 2008 Author Share Posted October 19, 2008 grumpyvette.........QUOTE "on deceleration only tends to indicate valve seals, or worn valve guides" I did another hot compression test today with all cylinder around 150 plus or minus 3 points. So that's all good. Also, I did a leak down test on all cylinders and all are nearly the same. This tests should rule out problems with rings, guides, valve seals and head gasket. I bit the bullet on removed the turbo system and found a very, very small amount of residue in the downpipe so I will have the seals replaced in the Garrett and try it again along with retuning the tech 3r. In my earlier post I mentioned using some coolant. Could I be leaking coolant through the turbo and that causing the white smoke? My cooling system uses a 25 psi cap. During the leak down tests, I put compressed air to each cylinder and could not make the water in the radiator move or bubble. TonyD.........You were correct about an exhaust leak causing the bad breathing condition in the cabin. The gasket between the Garrett and the downpipe was gone with the wind! Quote Link to comment Share on other sites More sharing options...
proxlamus© Posted October 20, 2008 Share Posted October 20, 2008 Mayo what are you running in regards to a PCV setup?! The residue in the downpipe is due to the oil being burned in the exhaust! I really don't think its necessary to change the seals! I mean its a good thing to do while your at it, but why mess with something that works fine?! Quote Link to comment Share on other sites More sharing options...
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