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Hello Everyone ! Im having a pretty serious problem here and would appresheate some help with this problem. Problem is I have alot of oil entering engine cylinder #4 to the very right causing it to burn clouds of smoke. I have done a compression test on all 4 cylinders results are 182, 2 -186, 3 - 181 , 4 - 185 PSI. I just have changed out the head gasket, problem still remains, smoking starts as soon as you start the engine and gets worse as the exhaust heats up. I aslo moved my turbo oil return line up higher. the turbo is not at fault there is no oil on the compressor side or exhaust side. checked my PCV valve ,its fine which im also using a catch filter to trap oil. when i removed the exhaust mainfold it was entirly soked with oil - not good . i know how this problem happended , a result of detonation. Turning my FMU knob the wrong way, (I feel very stupid). Im convinced that there is a leak somewhere in the head somewhere but im not sure. the engine runs perfactly idles smooth but oil is leaking in the cylinder. I know its not pulling oil in through the throttle so im baffaled because theres no overheating , compression is great, runs perfact, turbo seals are fine, and no machincal noise. If anyone has any idea what this could be or any tips or tricks to finding the sorce of oil leak it would be very much appreasheaded. Thank You !

Jsut a guess but maybe ur blowing oil past the rings cause ur rings got F*cked up? and the compression migth still read good cause u could of had alot of oil ontop of the clylinder (effectively sealing it) But nm cause i just read that it idles smoothly. hmm does ur VAC gauge jump around a lil periodicly? Maybe your pressureizing the crankcase (bad PCV valve??)

im just throwing stuff out there really to help...i dont know man.

did you check out your valve seals when your head was off?

Thanks for the quick responses. I did the compression test right after i changed the head gasket and cleaned the top of the piston. cylinder 4 was around 185 psi. after the engine runs for a few seconds and a thick layer of oil builds up on the piston, compression jumps up to around 220 psi and i have tested the pcv valve its still working luckly. I have a breather on the crankcase outlet which i blew in to check and make sure it wasnt clogged. I didnt check valve stem seal's only because i was convinced it was the head gasket. Im doubting its a crack in the head now that i think about it because it would think the cylinder would fill up with oil extreamly fast, so the only thing i can think of now is the valve stem seal's. would bad valve stem seals cause clouds of smoke ? I will check them. If anyone has ANY idea's plz let me know. Thanks !

If excessive oil is getting in the cylinder ur gonna make some smoke. Blueish smoke. Oil will either get in from the top (valve seals) or bottom Rings. Or ur turbo could be blowing oil into ur mtor...but then it would not be just cylinder 4 i suspect. HEadgaasker prob will burn more white smoke when ur burn the coolant and it should not run as good. Id assume its sumthing in the valve train.

Well, went to do some more investagating I noticed after doing another compression test on cylinder number 4 , after i pulled out the connector, oil was rolling down from the intake side to the exhaust side, i have seen it do this twice after compression test's, so im going to pull off the intake mani to see whats going on. All cylinders look oily , and all exhaust ports had oil in them as well, The only thing i wander about is my intake tube isnt really oily maybe a film but thats it. Guess ill find out when i pull off this intake mainfold, This is the first time i have this hard a time trying to pinpoint a problem. So much for expeirence

If oil is running down the intake pipe it sounds like your crankcase is pressurizing. Remove the pcv & it's vaccum line and cap off the vaccum connector on your Intake Manifold. Route a vaccum line from the valve cover crank case vents to seperate 20oz empty bottles, or the likes, leaving the cap off them so air can escape. Start the car and see if oil starts blowing into either of the bottles. If it doesn't....bring up the RPMs so the turbo starts pressurizing the system and see if it blows oil into either of the bottles. The PCV valve is only for venting the crank case preventing oil from blowing out of the valve cover vent into the IM and the other vent goes through a baffle under the valve cover for venting only the crank case (this is the one to watch for oil blowing out of). On race cars you want to use a vaccum pump system to seal the rings...thats how they get away with really lose piston rings for reduced friction & minimized blow by. If the bottles are accumulating oil at a rate you can see while watching the car run then your getting to much blow by and the rings aren't sealing or the head gasket is leaking and causing the problem. Cracked cylinder head is still a possibility but you should see it on a compression test by just that single cylinder being down on compression. Same with the head gasket. If it was the head gasket leaking you'd see two adjacent cylinders with similar but lower compression compaired to the others. If it is the head gasket then it is due either improper surface finish and prep of the cyl head and block deck or they have warped out of spec (need to be with in .003" flatness from end to end and diagonaly end to end). The surface finish for a MLS gasket should be minimum around 70ra for Fel-Pro MLS and 50ra for Cometic MLS gaskets (thats pretty much no machining lines left...shouldn't be able to feel any ridges with you finger nail).

P.S.

Prep both cyl head and block by scraping with a sharp razor blade and then wipe them both clean several times with acetone on a lint free cloths.

Nub Question:

How much are rings and a head gasket in US or Can.

so after pulling off the intake manifold (top part) the intake had a nice puddle of oil (in intake tube 4). cleaned it out . then i let the engine idle up to temp , (fan kicked on twice) let it run for about 15 mins to burn out any oil in exhaust.then I pulled out the plug and theirs oil back in the cylinder. thing is, is that the puddle of oil was in the intake plunnem on cylinder #4. so what dose this mean ? valve stem seal / valve guide ? no oil blows out of either the beather or the pcv hole, I had the intake tube removed during this test to watch for oil coming from the turbo, no oil even on rev. Any Idea's ? Thanks everyone !

So, out of frustration i have decided to pull the head back off , tear it down , and im going to take it to a machine shop to have it checked for cracks , get a 3 angle valve job (also check valve guides), new valve stem seals , and and checked for flatness. and put it back together using all new seals and im going to replace the thermostate. So wish me luck ! I will let everyone know how everything go's.

It is worth your time to yank that #4 piston out and clean it up. Inspect the top ring lands (aluminum grooves the rings sit in) for small cracks, especially the top land. The cracks are likely going to be on the intake side of the piston, if it's not bad enough that the piston falls apart when you pull it out

Ive had this problem before, and you definately need to get that piston out and do some inspection

I second that motion. You've already got the head off...I'd go ahead and drop the oil pan and rering the pistons. If you have the money you should go ahead and replace all the bearings and oil pump. Then you'll have a "new" motor. I've had great success with the Sealed Power Tri-Metal bearings and I'm switching up to Coated ACL race series bearings. I also recommend the Cometic MLS head gasket or the Fel-Pro MLS head gasket.

Thank's for all the quick responses ! So after the head rebuild which includes machine for flatness, 3 angle valve job, new valve stem seal's, pressure check, and cleaned, (not bad for $ 100 ) The problem still ezists but now im noticing oil in all 4 cylinders so the only thing left is the rings ....... . So now im going to pull out all four pistons to inspect to see if I need new pistons , rings or both. so besides removing the oil pan is their anything else i need too do to pull the pistons ? like will i have to pull the crank or will they just drop out ? thanks for everyones help.

If all you are doing is reringing the pistons then you'll have to pull the oil pan and the cyl. head. The pistons have to come out through the deck. Besure to mark each rod and rod cap as to they're cyl. # and which side was towards the front of the block. This is VERY important because if you put them in backwards or in a different cyl. you can cause uneven wear or vibration from unbalancing the assembly. Besure to use new bearings when reinstalling them.

Thanks for the great information. Also I think I will order a apex SAFC fuel unit, being as this problem was caused, by not enough fuel. I will let everyone know how the story ends.