Smoking Oil filler vent

[JUSTIN]

65 401 riv. This weekend I was fooling with something under the hood and I notice that smoke was coming out of the oil cap filler while it was idling. It has a pvc valve on the pass side valve cover. but the driver side doesn't have one. Is this normal? This is a rebuilt engine with about 10,000 miles on it. Car was warmed up but not hot.

[Guest]

I would check the pcv valve by rattling it to see that it isn't cloged. Check it for suction. <BR>The smoke could be from the oil buring off the contaminats that normally collect in it.

[ronvb]

That system only has 1 pcv valve and for the cost of a new one it should solve your smokin filler tube syndrome. PCV valve is a 1-way valve- you should be able to blow thru 1 side and not thru the other side.If air goes thru both sides -replace it.<BR>ronvb

[Guest]

Hate to break the bad news Justin, but what you might be seeing is a sign of worn rings. If your pcv valve is operating properly (check it first), then your engine is starting to show it's age. Usually excessive blowby at idle is the first sign that she's getting due for an overhaul.<P>See at idle there is very little airflow through the carb and as long as the pcv valve is working correctly a well sealing engine should not leak enough blowby gases so that idle airflow will not handle the residual gases.<P>Here's a test to see if your pcv if operating correctly, remove oil filler vent and plug with your hand. If a vacuum is felt then all is well with your pcv system and the little bit of blowby was only passing.<P>If you feel pressure then change the pcv valve and try the test again, if you still feel pressure then you've got worn rings. <P>Don't panic, a minor amount is acceptable and to be expected in a car of advancing years, and to be honest the older (pre 80's) car handled this rather well. But the crap coming out of your crankcase will clog idle ports, throttle plates and just about everything downstream of the pcv port, this includes your valve stems and sparkplugs.<P>Newer computer controlled cars don't handle this well and will usually start to give you all kinds of trouble codes indicating mixture problems etc. Many people start replacing sensors, sloenoids and actuators etc. When in reality the engine just has a lot of blowby because it is worn. In these situations I perform the highly illegal modification of installation of a "road tube".<P>Whats a road tube, basically many old cars had tubes to dump excess crankcase gases overboard through a tube draining onto the ground, this prevented contamination of incoming fuel/air mixture and the car ran the same even if it had a lot of blowby.<P>With todays emission controls all crankcase emissions go back in to the engine whether the engine likes it or not which is fine, until engine wear starts to take it's toll and the crankcase actually starts to become pressurized with blowby gases. <P>The computer controls were never designed to cope with this amount of mixture dilution and the computer goes through all kinds of coping schemes to try to compensate, usually generating all kinds of blinking check engine lights and just generally running strangely but not consistently. <P>The solution short of rebuilding the engine is to separate the crankcase emissions from the incoming air fuel mixture, usually after doing this the engine will return to it's original state after cleaning the accumulated gunk of off the airflow sensor wires, idle air control solenoid etc. All of the blocked fuel injectors I've seen were caused by these blowby gases condensing on the injector tips.<P>So if your computer controlled auto is starting to have drivability problems have a look at the blowby coming out the crankcase. Chances are excess blowby is causing mixture problems.<P>Of course removing a source of vacuum from the crankcase is not the best thing for horsepower production as the vacuum actually helps the rings seal, but if you've got a little "steam whistle" under the hood there won't be any vacuum anyway. The loss is negligable at only a couple percent.<P>Of course everything I've just told you is highly illegal and here it comes;<P>I DO NOT CONDONE THE DISABLING OF ANY EMISSION CONTROL DEVICE AND THE ADVICE OFFERED HERE SHOULD ONLY BE PERFORMED ON A COMPETITION OR OFFROAD VEHICLE. ANY MODIFICATION OF A EMISSION CONTROL DEVICE IS PUNISHABLE BY LAW.<P>with that out of the way you could now take your "offroad" vehicle and trash the pcv, retune the carb to take advantage of the fresh air now entering your engine, she will love you for it.<P>One other thing before I finish my rant, cold climates can cause a road tube to block up with ice (you will be amazed at the crap that comes out) if you live where the temps are below zero consider mounting the tube where the exhaust manifolds will heat it to prevent freezing. <P>Remember that you will now smell your noxious emissions if you are idling for any length of time with the interior fan on, I'm sentimental and I like to think it reminds me of the old days. <P>If you can't stand the smell and all this sounds like a waste of time, rebuild it. I know you said it only had 10K on the fresh rebuild, did you rebuild it? did the guy who sold it to you say that? As long as the pcv is working correctly there should be no gases escaping from the crankcase-period.<P>The number of times I've went to look at a car for friends and when I get there the guy tells me it only has 5K on the freshly "painted" motor, I pull the cap and look for blowby as soon as the engine is warmed up and do the pressure test. Most of these "deals" turn out to be too good to be true, and I walk away. <P>I do hope it's your pcv and it probably is but if it is not, I would do a leak down test and see exactly which cylinder(s) are causing the problem. Any leak greater than 7 percent is serious especially if it is only on one cylinder.<P>I wish you well, hoping the pcv is plugged.<p>[ 02-11-2002: Message edited by: Chuck da Machinist ]

[Guest COMPACTBC]

Justin, I had the same problem with my '64 425 engine, which needed a rebuild, but I didn't want to spend the $$$ then, so I installed a device called an EN-Valve, which replaced the PVC valve. This stopped all of my Blowby in to the engine compartment. The company that sells these is called EN-OVATION TECHNOLOGY, INC. 963 E. Detroit St., Chandler, AZ 85225, phone (602)963-6220. Check them out, their literature is impressive. <p>[ 02-13-2002: Message edited by: COMPACTBC ]

[JUSTIN]

Bruce,<BR>What does this do? Is it a filter. I hooked up a PCV to each valve cover and it seems to have solved the smell problem. I am concerned about the reason for the smoke/fumes though.

[Guest COMPACTBC]

Justin,I would suspect that your engine needs a rebuild or is very close to needing one, depending on the amount of blowby. A good indication would be more blowby while going up a steep hill with a fully warmed-up engine. Also another way to test your engine wear is to do a leak-down test.<P>The En-Valve uses the engine vacuum to keep the blowby inside the engine, contact them, their literature explains all about how the valve works. <p>[ 02-13-2002: Message edited by: COMPACTBC ]

[Guest]

<A HREF="http://www.envalve.com/" TARGET=_blank>http://www.envalve.com/</A> <P>A bit pricey at $60, but if it works as advertised, it'd be worth it to ditch oil leaks. ;-)

[Guest]

Sounds like snake oil selling to me, where's the photo of this wonderful device? Everything claimed in the literature could be accomplished with an open tube connecting the crankcase to the induction system. Where's the performance results and accompanying graphs showing reductions in exhaust emissions?<P>There is none because this is one of the oldest stories/scams in automotive history, a long time ago a very similar device was sold claiming much the same thing but was also claiming increases in power (there will be an increase in power when you place a vacuum under the rings).<P>This device also claimed to increase performance by reintroducing unburned gases and reusing this "wasted fuel".<P>Baloney, Baloney, Baloney!!!!!!!!!!!!!!!!!<P>The first tip off that this is a waste of money is the manufacturers claim that, and I quote;<P>---------------------------------------------<BR>Have some control over the air fuel mixture by injecting more air/blow-by as it develops under load. The leaner air/fuel mixture induces more complete combustion<BR>---------------------------------------------<P>Leaner, more complete combustion? What a load of BS. First of all it is no secret that blowby is mostly water vapor and contains exhaust by products that WILL NOT BURN AGAIN!!!! <P>As a matter of fact the Mfg's introduced exhaust dilution and crankcase blowby into the air/fuel charge to help reduce combustion temperatures, this helps reduce NOX production in the combustion chamber.<P>And as for the claims from people that have purchased the product claiming that their oil "leakage" has disappeared, I guess if you suck air in through a seal there won't be any leakage now would there?!<P>You want to create a vacuum in the crankcase and not dilute your air/fuel charge? Then do what every Nascar race car as well as any alky fueled circle track racer (you want to see condensation in oil!) has been doing for years, put a pitot tube in the exhaust stream where at least there is a temperature differential and very high flow rates to help evacuate the blowby gases.<P>The only thing that they have done with this product is put a blowoff valve into the device to limit the amount of vacuum put on the crankcase. The first iteration of this device didn't and consequently sucked gaskets and seals into the engine under high vacuum conditions!!!!!<P>I would welcome any reasonable discussion of this device with a rep from the company on this forum. This reminds me of the "fuel magnets" that get sold every few years or the spark "intensifiers" that are nothing more than resistors placed into the high tension wire.<P>This is SPAM and I suggest all of you treat it as such.

[Guest Mr. Solutions]

FINALLY! Thanks to "Chuck da Machinist" - somebody with some sense!!! I may not have the technical knowhow as to why this device may not work, but after taking one look at the web site, the very first thing that struck me as well is lack of photographs, lack of graphs... LACK OF ANY SUPPORTING INFO. Maybe it does take a Canuck to tell the Yanks the truth! <BR> <p>[ 02-15-2002: Message edited by: Johan de Bruin ]

[ply33]

I normally hang out in the AACA area, so I have missed most of this thread. A little technical correction on the nature of blowby:<P>Most of it happens on the compression stroke. The higher pressures on the power stroke have a tendency to seal the rings. Because of this, most of your blow by is actually your intake mixture and is perfectly appropriate to put back where it belongs: Into the cylinder to be burned. There are combustion byproducts (soot, water, acids, etc.) but the vast majority of the blow by is simply your fuel/air mixture.<P>To work properly the "road tube" or "draft tube" needs to extend into the air flow under the car in order to create a partial vacuum in the tube (venturi effect). Without that partial vacuum, it will not draw fresh air through the filter on the oil filler cap (or where ever your engine's fresh air inlet to the crankcase is). From this it is obvious that draft tubes do not work when the vehicle is stopped nor do they work well when you are driving slowly.<P>Positive Crankcase Ventilation (PCV) systems work well over a very wide range of engine RPM and road speeds. PCV does (or at least did not originally) stand for "pollution control valve". Positive crankcase ventilation is a good thing for your engine's life and has no real downsides. Your mileage may be slightly better with it (burning your blowby fuel air right!). Since the mixture of your blowby matches the mixture in your intake manifold you are not changing the fuel/air to the cylinder, so there is no drivability issues involved. The only down side is it cost the manufacturers a little more to make it.<P>It also turns out that the biggest source of unburned hydrocarbon pollution from a "uncontrolled" engine is from the crankcase. That's all that compression stroke blow by folks. You are spilling the contents of your gas tank out into the air.<P>PCVs appeared on a couple of high end cars in the 1920s because of the extended engine life they gave by helping to keep the crankcase clean. PCV valves were not used my the big manufactures until required for pollution control. The reason they did not use them was not for performance, drivability or fuel economy reasons. They simply did not use them because they cost more than draft tubes.<P>By reverting your car to using a draft tube you are decreasing your engine life, decreasing (perhaps unmeasurably) your fuel economy, and creating a "gross polluter".<P>Do yourself a favor: Fix it right. If it is only the PCV, then replace it. They are cheap. If your engine is tired and the rings are shot, rebuild it.

[Guest]

Without this turning into a "pissin match" and Ply33 you know that I respect your opinions, but some of the things you have mentioned are not quite correct.<P>"the vast majority of the blow by is simply your fuel/air mixture."---I would have to disagree on this, the 5 gas analyzer tests I have done on blowby gases show that it is mostly water and residual exhaust gases with a small component of fuel (10%). The fuel component decreases with coolant temperature and can get as low as 5% under full temperature idling conditions. Interestingly a large proportion of the heavy hydrocarbons I measured (presumably oil vapor) was the majority of the content (45%). Try burning it with a lighter, it doesnt burn.<P>"Since the mixture of your blowby matches the mixture in your intake manifold you are not changing the fuel/air to the cylinder"---I have to disagree, PCV valves are little more than a controlled air leak below the throttle plates which affects your airfuel ratio substantially. Your carburator will be calibrated to compensate. Try blocking it and do a gas analysis and you will see the mixture richen by one point at least.<P>"It also turns out that the biggest source of unburned hydrocarbon pollution from a "uncontrolled" engine is from the crankcase"----Blowby emissions contribute to 25% of emissions, 60% from your exhaust and the remaining from fuel vapor in the tank and fuel bowl. These are industry standard measurements and in no way reflect a worn engine, for those you can pick a number out of a hat.<P><BR>"By reverting your car to using a draft tube you are decreasing your engine life, decreasing (perhaps unmeasurably) your fuel economy, and creating a "gross polluter""-----Absolutely right on all counts except for the engine life part, I don't see how reverting to a road tube can shorten the life of a poorly running engine because of excessive blowby contamination of the fresh air/fuel charge. The engine will run better (after retuning) and plug life will probably double (remember the 45% oil vapor). Your right though the sucker will stink of crankcase gas all the time and you will be a gross polluter, like the steel mill at the end of town isn't.<P>The road tube concept is old and your right about it needing to be in the fresh air stream to work (forgot to mention that) but if you rely on the car for daily transportation and it's running crappy because of the blowby then it is an option that will get you through until the rebuild, not a remedy.<P>I still feel the exhaust pitot that the racers use is the superior, it puts the gases where they belong-in the exhaust. The Mfg's don't do this because the oil vapor would "coke up" the converter catlyst.<P>The only acceptable solution is to rebuild and that is what everyone here is recommending.

[old-tank]

Justin, if your engine has only 10K miles and runs good otherwise don't worry unless it is real apparent in July. Cool weather will make normal vapors condense and be more noticable; also if you have short trip driving habits the oil will have some of these volatile gases dissolved and will release when hot. Change oil, put in a 180-190 degree thermostadt, take a 100 mile trip on the interstate and see what it does. Excessive blowby will be manifested by puffing of smoke when idling if one piston/ring is defective; general wear blowby will have smoke blowing under pressure when you rev the engine with the oil filler cap off. Hope this helps.<BR>Willie

[Guest]

Chuck knows it all, the rest of us don't know jacks**t.

[ply33]

I am opinionated too. And it appears that there are some areas that Chuck and I do not see the same way. No big deal. But lets keep it civil.<P>"Unregistered User tired of Chuck" should at least have the decency to login in and let us know who you are.

[Guest]

Didn't mean to offend Ply33, certainly not meant that way. Silly subject to argue about anyway. <P>These unregistered users with the attitude are on every forum, I don't let them bother me. I'll probably get a virus in the mail from him, good luck!<P>I left a nice response in the Tech forum, just for him. Maybe the moderators can record his IP address for me since he stays logged in, I'd love to get that. Seems I have a nice little program just for him, not that I'm the vindictive type. <P>One last thing mr/mrs/ms unregistered user perhaps you should have a look at Ply33's website, this guy knows more about old Plymouths than I could ever hope to learn and in that regard I am his humble apprentice who knows when to keep his mouth shut, a skill you really could work on a little more. Who knows you might just learn something? I know I have.<p>[ 02-16-2002: Message edited by: Chuck da Machinist ]

[JUSTIN]

Well what bothers me is that I thought I had the factory setup. PCV on driver side and oil filler vent on passenger side. But when it idles smoke came out of the oil filler vent. and the whole car stunk. So I added a PCV to the driver side also and Teed into the other PCV line. Now it seems to smell better and I dont get the smoke from the oil filler cap at idle. SO it seems that the problem is fixed. My question is: Why did I have to do that? MY guess now is that the PCV on the driver side was bad (I haven't tested) or I have a problem with my rebuilt engine.

[Guest]

I tend to hear PLY. I rode in a 36 Dodge years ago and the blow-by was so bad you had to drive under 50. I believe him because he knows who "Invented" blow-by !

[rocketraider]

Justin, since adding the extra PCV valve do you still have a fresh air intake port for the PCV system? The oil filler cap/breather served that purpose on the old open systems.<BR>Engine needs a crankcase fresh air intake.<P>Later "closed" PCV systems took the fresh air from inside the aircleaner housing so if you had some blowby, it got sucked into the carb instead of blowing to atmosphere.