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Old 01-28-2004, 05:22 PM
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Is PCV Good or Not??

I have a 1965 Plymouth Belvedear with a 273 V8 2 barrel carb and automatic transmission.

I am trying to determine weather the PCV valve is good or not. I know the old trick if it rattles its good is not true. When the engine is idleing, and I put my finger over the end of the PCV valve, is the engine RPM supposed to change or not?

Also when I pulled the PCV valve out of the valve cover, the end of the valve was covered with a white milky substance. Any ideas what this is about?

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Old 01-28-2004, 05:34 PM
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PCV

Change the PCV just like you would change the air cleaner, if its dirty then change it. The milky white stuff is water in the oil. How long has it been since the oil was changed? An engine run but not long enough to evaporate the condinsation will foam. Don't panic, check the dipstick and see how much oil is in the oil pan, if the level is correct then Buy some good oil and a filter and change them both. Watch when you change the oil that as soon as the plug is out the oil runs and not water first, if you see a lot of water then you need to do some engine gasket work so hold off on the oil change and start pulling the head's off as you probably need a head gasket. May the Hot Rod God be with you Dude!


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Old 01-28-2004, 06:46 PM
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For the cost of it, about $4, change the PCV.
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Old 01-30-2004, 07:37 PM
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No pcv made for this car any longer

The problem I am having is finding a pcv valve. Evidently they do not make it for this car any longer because I have been to 6 parts stores and no one even has a listing on it.

I think I will try to mount a generic pcv valve in the hose going from the carb to the valve cover about mid way. That idea seamed to work on my chevy engine ok.

I drained the oil and did not see a trace of water in the oil but I did find some of that milky white substance on the end of the dip stick so maybe there is only a small amount getting in from somewhere. The radiator does not use any water than I can tell.

Any other comments or ideas??

I never did get my question answered. Is the rpm suppose to change when the engine is idleing when you cover the end of the pcv with your thumb?
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Old 01-30-2004, 11:29 PM
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HotRodMan,
You can put a generic pcv on your engine but I think yours will come apart so you can just clean it and then put it back on.
As for your question about pulling the valve out of the cover will the RPM change the answer is no if everything is working as it should. If you are running your engine on the rich side then pulling the valve at idle will allow fresh air to go into the engine and cause the RPM to go up. If on the other hand your engine is on the lean side then the RPM will drop just a little.
The white "stuff" is condensation. Caused by one of two things. Either your thermostat is stuck in the open position so the engine runs too cold which does not "boil" the moisture out of the air that is inside your engine from sitting over night. Or you only put on about one or two miles per trip. Again the engine doesn't get hot enough to get rid of the moisture so you get the gook on the filler cap and dipstick and under the rocker arm covers. If not corrected the inside of the engine will rust and start to flake and then you will really have problems.
Hope I helped
Scholman
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Old 01-31-2004, 05:36 PM
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I gather it's cold where you live? Don't worry, the last post's spot on. The older style of motor like yours just dose'nt get hot enough to burn off any excess moisture that's built up in the crankcase. Things like cool ambient and engine running temperatures, short drive durations and an inadequate crankcase ventilation systems can cause milky moisture deposits in the upper cavities in your motor - IE, under rocker covers, oil filler cap and in the dipstick tube area. This can be considered normal and never should be used to confirm a blown head gasket before checking other things first. Moisture is a byproduct of combustion. It's present in the crankcase and it's present in the exhaust - hence the white steam cloud from your exhaust when the exhaust system is cold! I test cars for a living - you know, pre-purchase inspections. And I'm forever arguing with potential buyers who think their future car's got a blown head gasket because of the creamy moisture droplets formed under the oil filler cap. I'll destroy this myth once and for all. I also test exotic cars and often find moisture under the oil filler caps of Porsche 911's. Now for those of you who don't know this, Porsche 911's are air cooled! So unless your losing water and have engine oil that looks like milk coffee I'd ignore what you've found and continue driving your car without any worries. Rob
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Old 01-31-2004, 06:56 PM
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Dude, never have I seen a milky substance on a dipstick that did'nt signify a problem with a coolant leak somewhere. You should have ONLY oil on the dipstick and on the filler cap.

Same thing started with my 87 olds. The first sign was the foamy yellow/white substance on the filler cap, but did'nt find any coolant in the oil yet. A few weeks later, foamy crap in the PCV valve, filler cap and a milky/oily dip stick. It had blown the head gasket on the passengers side and after letting it sit for 2 weeks before taking the head off I had two coolant stains bleeding down into the front 2 cylinders.

I dont care how "new" a car is, it should NEVER have anything other than a clear brownish, or dark brownish to black oil slic on the dipstick.

BTW the radiator in my olds never seemed to lose any coolant. The "boiling moisture" out of the coolant might not be BS, but I've been running my isuzu now since I bought it with a stuck open thermastat and it never even gets close to 160 deg. in hot weather, and since it's been cold as hell here the coolant doesnt seem to hot enough to register on the temp gauge. And guess what.. not a drop of coolant or water anywhere in the engine.
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Old 01-31-2004, 07:28 PM
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The white sludge build up on the oil cap in its self does not necessarily mean a problem. In colder climate when engines are taken on short trips it actually it quite common. If the engine does not reach normal operating temperatures often enough a build up of moisture in the crank case begins to occur. If you take it for a long run on the high way it will vaporize it and send it out the breather and pcv and you'll be right as rain. I would how ever definitely keep an eye on the coolant level to see if its dropping and maybe pressure test the cooling system which may show if the is a head gasket problem. Also next time after you take it for a drive open the rad cap CAREFULLY!! and look for bubbles. This is usually the sign of a cracked head or head gasket problem.
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Old 01-31-2004, 08:32 PM
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White milky could be simply condensation as stated,check the carter parts catalog,as in the carb people,they used to have pvc valves and manifold choke springs I had a hard time finding for a 273 mopar,Im not sure,its been awhile,but its worth a look.

Sometimes Ill just pull it out of the valve cover with the hose still on,give the engine a good rev and shoot some carb cleaner in and clean out the line and passage at the same,be outside though because it can stink.

Last edited by rifraf; 01-31-2004 at 08:32 PM.
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Old 01-31-2004, 11:01 PM
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I'll stand by what I said. You can get some moisture build up in the dipstick tube which would show up as moisture droplets/sludge above the oil line on the stick itself. This is perfectly acceptable as steam rises and pockets in the higher extremes, such as dipstick tubes, then condenses into water when cooled down. Has anyone ever seen the upper area of a dipstick become rusty - particularly on an auto trans? I wonder how that could occur?
87442 lover, you need to broaden your view on engines. I guess we should be thankful we don't have too many mechanics who tear down engines as soon as they show some milky condensation under oil filler caps. I suggest you go to your local used car dealer and look under the oil filler caps of the used cars on the lots. As these vehicle's just sit idle on the lot they quickly accumulate moisture in the upper areas of the motor. Don't get confused, if the OIL IN THE SUMP is saturated with coolant then you have a problem. But that does'nt mean you've got a leaking head gasket. A porous manifold or timing cover can be a cause as well as a corroded internal head or block freeze plug.
A good mechanic/come engine builder should in most cases, know where an internal leak is coming from. And if there's a blown head gasket, then the leaking cylinder/s should be revealed before the head is removed. There's several methods to do this but there's a simple and easy way and that's by using a sight glass. Rob
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Old 02-01-2004, 12:14 AM
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PCV valves have individual flow ratings. A generic PCV will work but the right one would be an improvement.
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