mikeshoup Posted September 2, 2006 Share Posted September 2, 2006 Okay, here's my ordeal. My XT Turbo with its higher compression block seems to have excessive oil coming out of the PCV system. When I first got it, it would shoot oil into the intake after long decelerations from a highway. I changed the PCV valve to an OEM valve. This didn't help really. I then deleted the PCV system per Phil's recommendations. Plugged the PCV valve up, and connected the two valve cover breathers to an air breather. Then plugged the holes left over in the air intake tubing. Now, I get a different problem. It shoots oil out of the air breather after coming off the highway. Does anyone have suggestions as to fix this problem? A thought I had was that the shortblock used doesn't have the crankcase breather that the turbo block does. But, Noss's wagon has the same setup I do (SPFI block w/ turbo heads), and his doesn't do it. I'm kinda at a loss. Haven't been driving the XT because I'm tired of oil getting everywhere. Link to comment Share on other sites More sharing options...
subyrally Posted September 2, 2006 Share Posted September 2, 2006 sounds a lot like blow by, do a compression test. almost sounds like the rings might be starting to wear out. that sounds like what happened to the first engine i had in my rx, it sat for a long time before i got to drop it into the car, and i thing that the rings had some rust on em. either way, around a 1000 miles after i got the car put together , i started getting a lot of oil in the intake, to the pointthat it stopped the turbo. when i tore down the engine, i found over an inch of a ring missing all together. like i said, get a compression test done to it. best of luck with that. Link to comment Share on other sites More sharing options...
calebz Posted September 2, 2006 Share Posted September 2, 2006 Okay, here's my ordeal. My XT Turbo with its higher compression block seems to have excessive oil coming out of the PCV system. When I first got it, it would shoot oil into the intake after long decelerations from a highway. I changed the PCV valve to an OEM valve. This didn't help really. I then deleted the PCV system per Phil's recommendations. Plugged the PCV valve up, and connected the two valve cover breathers to an air breather. Then plugged the holes left over in the air intake tubing. Now, I get a different problem. It shoots oil out of the air breather after coming off the highway. Does anyone have suggestions as to fix this problem? A thought I had was that the shortblock used doesn't have the crankcase breather that the turbo block does. But, Noss's wagon has the same setup I do (SPFI block w/ turbo heads), and his doesn't do it. I'm kinda at a loss. Haven't been driving the XT because I'm tired of oil getting everywhere. SOunds like the way my high compression turbo motor was acting before it assploded. oil freakin everywhere. +1 for blowby and boost leakage into the crankcase. Link to comment Share on other sites More sharing options...
Caboobaroo Posted September 2, 2006 Share Posted September 2, 2006 Yup, my RX is doing the same exact thing. I think I'm going to go with a stock turbo shortblock if I decide to keep the car. If not, part out city... Link to comment Share on other sites More sharing options...
mikeshoup Posted September 2, 2006 Author Share Posted September 2, 2006 Yup, my RX is doing the same exact thing. I think I'm going to go with a stock turbo shortblock if I decide to keep the car. If not, part out city... I half way have been considering going back to a turbo short block. This high compression motor has caused me too many headaches. But the car is just so fast right now. I don't think that this PCV problem is a result of the high compression though. Noss's (blownbimer's) wagon has basically the same setup, and it doesn't suffer from this problem. I suppose I should do a compression test. Need to go out and buy a compression tester now. Link to comment Share on other sites More sharing options...
NorthWet Posted September 2, 2006 Share Posted September 2, 2006 Do you just have the 2 cam-cover breather hoses? If so, do you get more/most oil from one, like the one on the turbo oil return side? Link to comment Share on other sites More sharing options...
mikeshoup Posted September 3, 2006 Author Share Posted September 3, 2006 I have both of the cam cover hoses connected to one breather in the center. But now that you mention, I have noticed the p/s one shooting more oil out than the other. This high compression motor has given me too many headaches. Link to comment Share on other sites More sharing options...
NorthWet Posted September 3, 2006 Share Posted September 3, 2006 I have some notions, but I can't think of a good reason why the engine would be experiencing positive crankcase pressure during engine braking (unless I misunderstand what you mean by "coming off of the highway"). My general feeling is that the turbo engine used the central oil breather/separator line to avoid this situation. And the situation, I think, is an excess of frothed oil in the non-disty side head due to the turbo's oil drain line feeding into that cam-housing. Between the quantity/quality of oil in that head's drainback, plus perhaps more blowby in the turbo'd engine, the frothed oil may be getting sucked into the cam-cover breather line. Calebz, did you ever do a postmortem on your engine to see what the piston/rings/cylinders looked like? Link to comment Share on other sites More sharing options...
mikeshoup Posted September 3, 2006 Author Share Posted September 3, 2006 Well, I do a long deceleration off of the highway, then the next time I step on the gas it smokes oil. It'll do it on the highway too if I'm cruising for a bit, then press the gas to accelerate. Link to comment Share on other sites More sharing options...
daeron Posted September 3, 2006 Share Posted September 3, 2006 possibly one of my boneheaded ignorant suggestions.. and i suppose it might be a band-aid style fix, but since it hasnt been mentioned i will open my big mouth.. what about one of those fancypants catch-cans? are you more concerned about finding the issue causing the oil than the oil itself? Link to comment Share on other sites More sharing options...
NorthWet Posted September 3, 2006 Share Posted September 3, 2006 Well, I do a long deceleration off of the highway, then the next time I step on the gas it smokes oil. It'll do it on the highway too if I'm cruising for a bit, then press the gas to accelerate. So, similar to the typical oil smoke from worn valve-guide seals? I assume that you aren't seeing the oil smoke with the breather setup... when does it spew oil with the breather? Or do you just see it all over the engine when you stop? Link to comment Share on other sites More sharing options...
mikeshoup Posted September 3, 2006 Author Share Posted September 3, 2006 Or do you just see it all over the engine when you stop? Yup, that's the case. Link to comment Share on other sites More sharing options...
NorthWet Posted September 3, 2006 Share Posted September 3, 2006 So, my guess is that the general problem is like I outlined earlier: Whatever blowby there is getting sucked (pre-breather-configuration) into the intake tract and dragging oil froth with it, or post-breather-config it is just venting to the breather and dragging the froth with it out over your engine. The nasty part of all of this is any oil in the intake charge will promote detonation, so if this went/goes on long enough you are going to kill your ring lands, causing more blowby, etc. And the breather setup is just plain unhealthy for the engine. A couple things that I might try (I am planning a hi-comp turbo, but now have a N/A MPFI block as a base) would be to reconnect the PCV valve to the disty-side cam cover, possibly with a plenum chamber directly above the cover (cut down the velocity of any entrained oil so that it falls out of entrainment); do something similar on the non-disty side plus run it to a larger "condensator" to try to wring out any vapors or mist, and then either plumb that to the air intake like stock, or run it to a breather. Something else that might help is, rather than use the cam-cover connection on the non-disty side, fab a connection to the oil filler tube and run that to the intake. Higher and farther away from the turbo drain return, larger diameter so less air velocity so less entrainment. I would probably still use a plenum and/or condensator on this line. Now this could all be BS if my initial premise is wrong... :-p Link to comment Share on other sites More sharing options...
calebz Posted September 3, 2006 Share Posted September 3, 2006 Calebz, did you ever do a postmortem on your engine to see what the piston/rings/cylinders looked like? Nope, all post mortem info at this point is strictly conjecture. I have opened the hood twice since it blew up. Both times to show my custom IC y pipe. The car is still sitting in the driveway outside the garage bay it usually lives in. When it blew up I was about 3 miles from home and I said hell with it and drove it till it dropped. Namely, the last 3 miles home. It stopped in the driveway:clap: Link to comment Share on other sites More sharing options...
NorthWet Posted September 3, 2006 Share Posted September 3, 2006 ...and drove it till it dropped. Namely, the last 3 miles home. It stopped in the driveway:clap: A truly noble steed... got you home before it expired. Link to comment Share on other sites More sharing options...
kingbobdole Posted September 3, 2006 Share Posted September 3, 2006 Just so you know mike, my 6 has started to do this as well when I'm hard on it as well.. I have NO IDEA how the oil gets that far up and out that filter, but it manages. Heres a question for the group... How do we all feel about plugs? Just plug the damn thing totally off. Do the gasses really need to escape that badly? Other then that how about a screen in the tube? maybe some mesh to help keep the oil down. Link to comment Share on other sites More sharing options...
NorthWet Posted September 3, 2006 Share Posted September 3, 2006 ... How do we all feel about plugs? Just plug the damn thing totally off. Do the gasses really need to escape that badly? Other then that how about a screen in the tube? maybe some mesh to help keep the oil down. Gasses will come out somewhere, so it is better to be controlled ventilation than blowing seals. And/or getting a case explosion! Mesh in and of itself would have little effect. Need to slow the velocity of the vent gasses and cool them down. I just had a radical idea... create a "syphon tube" (dumb name, but can't think of something better) in the exhaust pipe past the turbo. Exhaust gasses would create a depression to draw the gasses out. Use metal line to run to it (eliminates chance of igniting mixture in tube/case) and a check valve (PCV?) to deal with pressure reversions. CatCons might not like it if you dumped a lot of oil, though. Link to comment Share on other sites More sharing options...
blownbimer Posted September 3, 2006 Share Posted September 3, 2006 I don't think that this PCV problem is a result of the high compression though. Noss's (blownbimer's) wagon has basically the same setup, and it doesn't suffer from this problem. Just FYI mike...my wagon did this too...not nearly as bad as your describing, but the pass side filter was always moist....How about being ghetto and running some sort of catch can to keep the oil from going everywhere as a temp fix? Good luck! Link to comment Share on other sites More sharing options...
NorthWet Posted September 3, 2006 Share Posted September 3, 2006 Oh, and I forgot to state the obvious: Make sure that the cam-cover breather is not narrowed by caked goo. I have seen quite a few that were narrowed to only a fourth of their nominal diameter. This would cause lots of oil entrainment. Link to comment Share on other sites More sharing options...
Caboobaroo Posted September 4, 2006 Share Posted September 4, 2006 mine seems to have a little more oil coming from the driver side, but the passenger side does it almost as much. It started doing it when I got hard on it one night. I didn't have any breathers or hoses on it, just open valve covers. Link to comment Share on other sites More sharing options...
mikeshoup Posted September 5, 2006 Author Share Posted September 5, 2006 Bought a compression tester today. Here's the results: Dry: 1 - 90 2 - 125 3 - 120 4 - 130 Wet: 1 - 130 2 - 150 3 - 155 4 - 145 So, the dry reading of cylinder 1 is definitely low. With the wet test, the reading of cylinder 1 is a bit better and doesn't show as much of a discrepency. So, what does this show? Worn rings on piston 1? Link to comment Share on other sites More sharing options...
Cougar Posted September 6, 2006 Share Posted September 6, 2006 Yes, it looks like the rings are bad in #1 but the others are a little low also. It looks like you need to dig into the engine to fix this. Link to comment Share on other sites More sharing options...
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