brianpavlovic Posted October 3, 2004 Posted October 3, 2004 Is it true that when the PCV Valve becomes clogged or dirty, it will push the oil through the seals? Could someone explain PCV Valves and how they work? All I know is that PCV stands for Positive Crankcase Ventilation, but how can it "push" oil through the seals? "i just had an estimate from the City garage around the corner frm my house (they do AWESOME work, have been taking cars there for a while, as have my parents, and their friends) and i was quoted $311 labor only for front and rear Valve Cover Gaskets and PCV valve. he said (and this is all true) that if the PCV valve is bad (or clogged) then it will push all the prssurized oil out through the seals."
Avatar Posted October 3, 2004 Posted October 3, 2004 I've never heard or read that, and have owned and maintained many, many cars since 1958. Anyway, long before you are at risk of that, you should have a "check engine" light on your dash. The check engine function is mostly tied to the pollution control functions; even a faulty gas cap gasket will thro a light.
Steve Posted October 3, 2004 Posted October 3, 2004 surely the pressure would simply blow out the blocked PCV from gunk.
amf1932 Posted October 3, 2004 Posted October 3, 2004 All I know is that PCV stands for Positive Crankcase Ventilation, but how can it "push" oil through the seals? If the PCV valve is stuck in a closed position excessive pressure is built up in the crankcase which in turn could push the oil through the seals. I would check out the operation of this valve to make sure its working properly, besides it's an inexpensive part. ;)
SKperformance Posted October 4, 2004 Posted October 4, 2004 It is true. It actually is not that hard to make oil pass the seals as the rubber is only slightly touching the metal parts to remove excess lube/oil to keep it from entering the combustion chamber.If it was tight enough to pressurize the selas then they would wear out very easily from the high amount of friction. A pcv is just as noted above. It works by reducing blowby gasses from the block caused by normal operations or from worn rings. This is basically vapoured oil /gas and any other contaminent. By law it cannot be legally exhausted to the atmosphere (reason why thoses little breather filters are illegal). Also it would leave oil deposits on the road from days gone by. Now it has to be reintroduced to the intake to be burnt off during combustion to be released. Also it needs to be their to reduce the pressure from the block which with heat can get rather high can cause backfiring and other drivability problems especially if the seals or rings are worn. With no pcv you would have to release the pressure somewhere. Btw if a pcv (like my neibours lastnight) is so old and has enoguh crud holding it together it will eventually bake itself and cake the oil to a perfect soild. Good luck if it moves again.
MNJack Posted October 4, 2004 Posted October 4, 2004 Do I HAVE a PCV valve?? 1997 ES300. I bought a PCV valve and gasket, the valve is L-shaped, ie has a 90 degree angle. I can't find anything like it coming out of the valve cover.
amf1932 Posted October 4, 2004 Posted October 4, 2004 Do I HAVE a PCV valve?? 1997 ES300. I bought a PCV valve and gasket, the valve is L-shaped, ie has a 90 degree angle. I can't find anything like it coming out of the valve cover. ← Yes, you do have a PCV valve and its connected to the valve cover. If you can't find it go to your neighborhood friendly mechanic to point it out to you. :)
mburnickas Posted October 4, 2004 Posted October 4, 2004 Do I HAVE a PCV valve?? 1997 ES300. I bought a PCV valve and gasket, the valve is L-shaped, ie has a 90 degree angle. I can't find anything like it coming out of the valve cover. ← It should be the same as my 98. If you are looking at the engine from the front, it is lon the left side near the belt area.
MNJack Posted October 5, 2004 Posted October 5, 2004 thanks for the directions! If I still can't find it maybe I will post a pic. I would be too embarassed to ask my "friendly local mechanic" plus I wouldn't trust him anyway! :)
SKperformance Posted October 5, 2004 Posted October 5, 2004 it is on the rear bank not the front, look for a hose going to the intake manifold.
steviej Posted October 5, 2004 Posted October 5, 2004 do a search on PCV valve, there was a thread about a year or a year and a half ago that had pictures. steviej
MNJack Posted October 5, 2004 Posted October 5, 2004 Thank you all! :) I found it, I changed it. Didn't change the grommet. The old one looks as good as the new one.. blows fine. It sure is tucked way back there. Reminds me of the first time I changed my own oil Took me 30 minutes to find the oil filter!! I almost gave up after scouring the underside of the car over and over again. I have only worked on old American cars. Oil filters, PCV valves, and ...... FUEL FILTERS, are a bit easier to get to on the older american cars!!
ArmyofOne Posted October 5, 2004 Posted October 5, 2004 Is it true that when the PCV Valve becomes clogged or dirty, it will push the oil through the seals? Could someone explain PCV Valves and how they work? All I know is that PCV stands for Positive Crankcase Ventilation, but how can it "push" oil through the seals?"i just had an estimate from the City garage around the corner frm my house (they do AWESOME work, have been taking cars there for a while, as have my parents, and their friends) and i was quoted $311 labor only for front and rear Valve Cover Gaskets and PCV valve. he said (and this is all true) that if the PCV valve is bad (or clogged) then it will push all the prssurized oil out through the seals." ← it appears as if the PCV is not my only problem... cam and crank seals are my enemy at this point. I have only worked on old American cars. Oil filters, PCV valves, and ...... FUEL FILTERS, are a bit easier to get to on the older american cars!! i hear that...
brianpavlovic Posted October 6, 2004 Author Posted October 6, 2004 Well, I finally got the car back! It turns out that my PCV valve was bad and that was in turn causing the blue smoke and not the dreaded valve stem seals!
ArmyofOne Posted October 6, 2004 Posted October 6, 2004 glad to hear it.....if only mine were that simple. :(
brianpavlovic Posted October 6, 2004 Author Posted October 6, 2004 Do you think that a dirty PCV valve could have caused your other problems? The Lexus mechanic said that if I had waited longer to fix it, that it would have ruined x-mas and he was not laughing! -Brian
ArmyofOne Posted October 6, 2004 Posted October 6, 2004 oh i have no doubt in my mind thats what caused it. but i cant fix it at the moment. i dont have time, and i dont have $$$$ to pay someone to do it. so for now shes just gonna have bad seals. the guy that had it beofre me knew nothing about cars (obviously). to say the least.
brianpavlovic Posted October 6, 2004 Author Posted October 6, 2004 Have you thought about running Valvoline Max-Life Synth 5W-30? I started using it and the car seems to run much better! They said that it "conditions" the seals and helps improve over all performance. Just a thought! p.s. Has anyone seen the special on the Discovery Channel about the 2005 Mustang and the 2005 C6? I was happy to see some "guy" tv for once! Does anyone know if there will be any Lexus car shows in the fall? Some of these weekends are turning into some pretty good driving weather! -Brian
ArmyofOne Posted October 6, 2004 Posted October 6, 2004 Have you thought about running Valvoline Max-Life Synth 5W-30? I started using it and the car seems to run much better! They said that it "conditions" the seals and helps improve over all performance. Just a thought! p.s. Has anyone seen the special on the Discovery Channel about the 2005 Mustang and the 2005 C6? I was happy to see some "guy" tv for once! Does anyone know if there will be any Lexus car shows in the fall? Some of these weekends are turning into some pretty good driving weather! -Brian ← i am running dino Max Life 10w30...i dont think itll help, but we will see. here: other than the massive amounts of oil leaking (probably a half a cup a day)... :rolleyes: shes 15 years old (yes i realize you are referring to the 92-present ES series, but mine has an ES badge too)..so here it is in full detail. Parts/Labor needed: (al of this caused by a clogged PCV valve that started at 90K and is still an issue now, at 140K) -Crankshaft Seals. -Rear Main Seal (possibly) -Valve Cover Gaskets -Water Pump w/Gasket (leaks a little) -Camshaft Seals. -PCV Valve -Spark Plugs -Spark Plug Wires -TIMING BELT (original is still on the motor :egads: its a "while you're in there" thing when you are doing cam and crank seals...as is the WP) all that stemmed from a PCV valve that wasnt changed in a timely manner...i HATE people who cant maintain their cars. -Serpentine Belt -Rear Brake Pads -Left Foglight out (yellow) -Front End Alignment -Decompressed Front Strut (i can copmress and decompress with my hand when the car is on a jack... :eek2: ) -Broken Cassete Deck (doesnt play or eject tapes) -Paint Peel -Bad ATX tranny mount (rear) -Burnt out Rear door lock actuator on drivers side...(meh, i can live with THAT) -Broken P/W & P/L Switch on drivers door. -Left liscense plate lamp out -Loose snap on gray trim along bottom half of doors...least of my concerns at this point. as it stand rigth now the only fluid that is not coming out of my car is Windshioed washer fluid/Pwer steering fluid/Brake Fluid/Tranny Fluid. its leaking everything else. Please remember this car is 15 years old, thats older than a few of y'alls kids. please be nice. its not lexi's fault she wasnt maintined properly. thats a list of everything i know of thats wrong with the car.
andrecat112 Posted October 12, 2004 Posted October 12, 2004 It is true.It actually is not that hard to make oil pass the seals as the rubber is only slightly touching the metal parts to remove excess lube/oil to keep it from entering the combustion chamber.If it was tight enough to pressurize the selas then they would wear out very easily from the high amount of friction. A pcv is just as noted above. It works by reducing blowby gasses from the block caused by normal operations or from worn rings. This is basically vapoured oil /gas and any other contaminent. By law it cannot be legally exhausted to the atmosphere (reason why thoses little breather filters are illegal). Also it would leave oil deposits on the road from days gone by. Now it has to be reintroduced to the intake to be burnt off during combustion to be released. Also it needs to be their to reduce the pressure from the block which with heat can get rather high can cause backfiring and other drivability problems especially if the seals or rings are worn. With no pcv you would have to release the pressure somewhere. Btw if a pcv (like my neibours lastnight) is so old and has enoguh crud holding it together it will eventually bake itself and cake the oil to a perfect soild. Good luck if it moves again. ← how and where does a breather filter fit into the picture?
ArmyofOne Posted October 12, 2004 Posted October 12, 2004 It is true.It actually is not that hard to make oil pass the seals as the rubber is only slightly touching the metal parts to remove excess lube/oil to keep it from entering the combustion chamber.If it was tight enough to pressurize the selas then they would wear out very easily from the high amount of friction. A pcv is just as noted above. It works by reducing blowby gasses from the block caused by normal operations or from worn rings. This is basically vapoured oil /gas and any other contaminent. By law it cannot be legally exhausted to the atmosphere (reason why thoses little breather filters are illegal). Also it would leave oil deposits on the road from days gone by. Now it has to be reintroduced to the intake to be burnt off during combustion to be released. Also it needs to be their to reduce the pressure from the block which with heat can get rather high can cause backfiring and other drivability problems especially if the seals or rings are worn. With no pcv you would have to release the pressure somewhere. Btw if a pcv (like my neibours lastnight) is so old and has enoguh crud holding it together it will eventually bake itself and cake the oil to a perfect soild. Good luck if it moves again. ← how and where does a breather filter fit into the picture? ← a breather filter rplaces the PCV valve. it is illegal in most states. the fumes/oil must be put back into the ntake system to be burned...hence, Positive Crankcase Ventilation. a breather filter releases the vented pressure into the atomosphere...not legal, and it WILL fail an inspection.
ArmyofOne Posted October 12, 2004 Posted October 12, 2004 what i would have said army ← thanks :D i am a DIY MECH TECH LOL. im a mechanic only by hobby, usually on older american cars, but a car is a car, you just have to get to know it or study it a little before you got the ins and outs. and every engine operates off of the same priciples. a PCV valve will do the same thing on a Dodge Viper that it does on a VW Bug. so will a spark plug. theres a lot to the complexities of engines, but after a few days of searching the net, most DIY'ers can do anything they will ever need to to a car...for the most part. but i have grwn up around engines, so heh, i have a backround LOL.
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