I'm running a 5.0 Ford motor and am having problems with oil smell coming into the cab of my truck. It's worse during hot weather or running the engine harder. I have the PCV valve connected to the valve cover and to a strong vacuum on the intake. The other valve cover has a push in type breather. I'm not getting oil blowby just the oil fumes and smell coming out the breather. Any suggestions or tips?
Turn your PCV system into a closed PCV valve system. Get a breather for your valve cover that is not open but has a hose connection on it. Run the hose up and connect it to the air cleaner with a small filter elelment. Normal operation... the air is pulled through the little filter element inside the air cleaner into the breather and on to the crankcase. Under heavy loads or a worn engine, the PCV valve may not be enough. The fumes back up into the air cleaner and are sucked down the carb. Sort of like an over flow. This is a 76 Malibu. I don't know when they mandated closed PCV valve systems on new cars but it's been that way for a long time. I've never looked for a chrome one but I bet someone makes one if that's an issue for you.
I'm running a billet oval air cleaner with a K&N filter. I tried that method before by using a breather with the nipple for a hose. I drilled the bottom aircleaner plate, tapped it and put a hose bib on it, connecting a hose from the breather to air cleaner. Didn't help much because the fumes went through the air filter element. I didn't have a filter at the end of the hose bib though. I noticed it made my air filter alot dirtier as well. Maybe some type of filter mounted to the base plate will help??
If it made your air filter noticeably dirtier in a small amount of time - you DO have blow by problems! Maybe you need to seal up holes in the firewall as well???
Your probably correct about the holes needing to be sealed up. I'm just looking for a better way to reduce the smell of oil coming from my current breather. I'm not blowing oil. Every engine is going to have an amount of oil smoke coming from the engine. Oil get hot and smokes. That smoke also has a oil film after a period of time. That's what was making my air filter dirty. I've notice on drag racing cars they have a breather with the hose connection and connect a hose to that. I see the hose runs down along the valve covers and appears to drop down to the frame. Anyone have info one this method and what they are using?
Oh the humanity. Blow-by does smell like oil. If you don't have smoke comming out of the breather you might just check and make sure that you don't have oil dripping on your exhaust. Even a small leak becomes larger when you get one hot and the oil thins out. Your other option is what Tommy already mentioned, but on a healthy mill that shouldn't be necessary.
When using a PCV valve you really shouldn't see or get much if any smoke out of the other breather if the motor has good ring seal. The Positive Crankcase Ventilation is creating a vacuum that should be sucking the vapors out of the motor and into the intake for recirculation in the combustion chamber. When you shut it off, you will get some smoke and vapor, but a tight motor shouldn't really have much when running if the PCV system is working correctly. As for the drag racers, there are a couple of different things you could be seeing. One is a pan e vac type system where those hose go down to s gulp valve on the exhaust and use the exhaust to and create negative pressure in the engine. The other is where guys just run the breather hoses in to a breather box or sometimes into a boxed frame rail and let the vapors exit there.
Ok, seriously. If the valve cover has a push in breather, get a push-in breather with a hose fitting on it. I'd run the hose down to the frame and past the back of the cab.
if you have a road draft tube and breathing oil filler, and you just run a hose from the draft tube to up-stream of the carb, no pcv just suck from the draft tube? this is on a friends stock 1930 chrysler 6, maybe a little off topic, its smokes when your ideling at a light.
I didn't like the oil and exhaust smell in my Studebaker truck, so I did exactly what the posts above recommend. I added hoses to any and all vents, then ran them elsewhere where the fumes couldn't possibly get into the cabin. I have had that on the truck for many years. It worked like a charm. If you have a "road tube" system instead of a positive crankcase ventilation system (PCV NOT PVC), make sure the lower road tube exit has a little pull from the passing air-flow just like the original system (exits into the moving air under the car, which ends up pulling vapors out of the tube), and the hose you run from the breather vents has a slight positive pressure, just like the original system (original was right behind the fan. I put mine in "neutral air" and let the other tube in the airstream do the pulling). I zip-tied the end of the road tube hose to the underside of a crossmember under the bed, facing rearward, where the passing air would help pull fumes out from the hose. The hose from the old filler cap was routed into the air cleaner, ON THE HIGHER PRESSURE SIDE inside the filter can (before the filter element) but NOT inside the filter element (very similar to post #2 above). If you put the intake-vent hose inside the filtered area itself, you get a slight low-pressure area that you do not want. That stopped the oil smell from getting into the cabin.
Thanks for the great advice everyone. I'm not sure which way to go at this time but am looking at maybe running the line down along the frame and out the back. I noticed the hose from the PCV is connecting to the nipple on the Holley carb I'm running, not the intake manifold directly. If I remove the PCV valve it functions correctly and seems to have good vacuum from that Holley nipple at the back of the carb. BTW- I ran that carb on a SBC and it ran great! I may try to find another vacuum source off the intake.
This is the installation I will be doing to vent the crankase. This is an original Draft tube from 1955 to 57 T Bird. Frenchy
I had a 56 chevy truck that had a draft tube, so I just cut the end off a garden hose clamped it on there and run the rest of it down the frame rail to the rearend. It was just a parts chaser.
Finally installed the down draft tube no problem no leaks and did take care of the pressure build up in the cranckase. I have the main cover being chrome to match my oil filter cover. Frenchy
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