Topher88 Posted June 23, 2011 Report Share Posted June 23, 2011 So i just drove my car for the second time ever yesterday and noticed some white smoke coming from my engine. The crank breather dose not have anything hooked up to it and everything around that area is soaked with oil... would my best bet be to just tart looking for a new motor? Quote Link to comment
Z-train Posted June 23, 2011 Report Share Posted June 23, 2011 Is your PCV hooked up? Quote Link to comment
MetalGear1200 Posted June 23, 2011 Report Share Posted June 23, 2011 my engine does this too.... Quote Link to comment
Topher88 Posted June 23, 2011 Author Report Share Posted June 23, 2011 nope the crank case to pcv pipe is not connected in any way Quote Link to comment
Topher88 Posted June 23, 2011 Author Report Share Posted June 23, 2011 i was going to hook up some sort of pipping to connect the 2. correct me if im wrong but isnt the PCV the valve coming off the manifold? Quote Link to comment
Topher88 Posted June 23, 2011 Author Report Share Posted June 23, 2011 and when i hold my thumb down on the crank tube there is not enough pressure to blow air past my thumb Quote Link to comment
MetalGear1200 Posted June 23, 2011 Report Share Posted June 23, 2011 quick google, most likely there is too much oil in the engine. aparently this happens to motorcycles alot Quote Link to comment
Topher88 Posted June 23, 2011 Author Report Share Posted June 23, 2011 Oil was about 2q low lol Quote Link to comment
rpowell25 Posted June 23, 2011 Report Share Posted June 23, 2011 Hence the Positive part of PCV acronym. The PCV uses vacuum from the intake to pull the crankcase fumes. Just venting to atmosphere will not typically work...especially on an engine with high mileage. To prevent this type of behavior you should have a vent from the valve cover to the air cleaner and the crank case pipe connected to the PCV on the intake. Quote Link to comment
MetalGear1200 Posted June 23, 2011 Report Share Posted June 23, 2011 but what if i dont have an air cleaner? Quote Link to comment
Uncle Laulau Posted June 23, 2011 Report Share Posted June 23, 2011 Oh man I just opened mine up today, check out 521 opening my crank case. Small world. I hope mine doesn't start smoking. Yikes. I need to pull the old smashed pipe out before I can hook it up proper like. Good luck frendo. Uncle Laulau Quote Link to comment
rpowell25 Posted June 23, 2011 Report Share Posted June 23, 2011 Also, if you are seeing a large amount of oil around the crank case vent you could have a fair amount of blow by. Check your compression. Quote Link to comment
rpowell25 Posted June 23, 2011 Report Share Posted June 23, 2011 Metal gear, if you have your crank case connected up to the PCV then you can get by with venting the valve cover to the atmosphere....not optimum but..... Quote Link to comment
albyneau Posted June 23, 2011 Report Share Posted June 23, 2011 but what if i dont have an air cleaner? Well, depending on how long it's been like that and where you drive, that could've been the problem. Even on clean roads there's enough undercar turbulence to carry already flying debris from the wind (or car in front of you) into your intake. Large fans and low cars exacerbate the problem. If it's as bad as it sounds, hookin up the PCV & filter's akin to the ole barn door~ the cows' already done runnoft. But plan for the worst, hope for the best, and get the stuff hooked up for the time being. You'll save a bit of oil $ and not leave so much of a snail trail of evidence behind you... You might want to check your plugs to see which (how many) offending cylinders you have as well, if you haven't done so already.... Peace~ Scott Quote Link to comment
MetalGear1200 Posted June 23, 2011 Report Share Posted June 23, 2011 i have filters, but i have a custom manifold with ITB's so i nowhere to hook that stuff up. Quote Link to comment
Elkie Posted June 23, 2011 Report Share Posted June 23, 2011 Ideally the pcv will have a source of vacuum to pull vapor from the crankcase and dump it into the intake after the throttle body before the head to be reburned, the valve cover is hooked up after the air filter before the throttle body to supply the crankcase with fresh air. If the pcv is not hooked up, everything is gonna go through the valve cover. Positive pressure caused most likely by blow by, will dump out there, when there's negative pressure your engine will suck in air there and whatever happens to be near it. If nothing else attach a long hose to the valve cover where it can dump anything out and hopefully filter anything before it gets back in. Fuel vapor will also mix with oil causing it to lose viscosity quicker, so keep an eye on oil as well. Quote Link to comment
Topher88 Posted June 23, 2011 Author Report Share Posted June 23, 2011 if a ton of oil is coming out of the crank case wont that just go right into the PCV valve? or since the PCV is at a higher elevation the oil will just drain back into the case? Quote Link to comment
ggzilla Posted June 23, 2011 Report Share Posted June 23, 2011 The purpose of the PCV valve is to prevent pressure build up inside the block. It goes beyond a simple vent in that it provides "positive" ventilation. Active versus passive. If it is not hooked up and the block tube and rocker tube blocked, pressure builds up in the engine. The purpose is not to suck up oil. Only fumes. If your rings are shot it will overload the vent (leak oil) or overload the PCV. Quote Link to comment
Elkie Posted June 24, 2011 Report Share Posted June 24, 2011 pcv, or the lines to it, usually have some sort of baffling to prevent oil from exiting the crankcase. When the engine is running, oil becomes a mist (think of spraying a hose into a fan). If you have blow by meaning gas is going around the piston into the crank case, this will cause positive pressure in the crankcase. This pressure will vent wherever is the easiest, in your case the valve cover. The air with the oil mist is coming out through your valve cover. You really shouldn't have positive pressure, which is why people are recommending you check compression, as nothing should be going around the piston. Your currently venting to atmosphere which is better then just plugging the lines, as the pressure will find some way to get out, like a headgasket. With the entire system in place it keeps a somewhat consistent pressure while also feeding fresh air, for a longer lasting engine. Quote Link to comment
Topher88 Posted June 24, 2011 Author Report Share Posted June 24, 2011 Nothing is coming out of the valve cover. Just the crank case line that is a hard lining coming from the block under the exsaust manifold and L's out to nothing since the 7/8th hose (crank case) to 5/8th (PCV). Do I have that correct? Quote Link to comment
Elkie Posted June 24, 2011 Report Share Posted June 24, 2011 Yeah that line usually runs back into the intake manifold, musta misread something above. You could plug it, as now its just venting the contents of the crankcase, then run a line from the valve cover down towards the motor mount. Or just run lines from both, keep a close eye on oil level Quote Link to comment
Siqx20 Posted June 24, 2011 Report Share Posted June 24, 2011 my engine was doing the samething since i bought it. on the way to canby i blew the motor. bad rings was the problem. to much piston blow by was over pressurizing the crank case. It went from a little smoke to alot in like no time, that would be my guess. do a leak down test. or atleast a compression test. Quote Link to comment
Siqx20 Posted June 24, 2011 Report Share Posted June 24, 2011 Nothing is coming out of the valve cover. Just the crank case line that is a hard lining coming from the block under the exsaust manifold and L's out to nothing since the 7/8th hose (crank case) to 5/8th (PCV). Do I have that correct? yes you do. and yes that is just going to pump all that oil into ur pvc and back into ur cylinders to be burned off. either way u will be losing/burning oil. Quote Link to comment
datzenmike Posted June 24, 2011 Report Share Posted June 24, 2011 There should be a baffle on the inside of the block before the block vent tube. It looks like folded up fly screen that filters out all the oil spray droplets. The PCV has a very small orifice so not a lot of blow by goes through it. It uses manifold vacuum and that is lower when driving than at idle. At higher speeds the majority of blow by will find the easier path out the valve cover breather. Stock, the valve cover breather is connected to the air filter and the carb will suck the fumes in so all of it ends up going through the motor one way or the other anyway. Quote Link to comment
ggzilla Posted June 24, 2011 Report Share Posted June 24, 2011 Yes something like this. Fits up inside the block, behind where the breather hole is. Their is a little bracket holding it in. Quote Link to comment
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