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My nearly new carb air cleaner element got very dirty along the inner surfaces. I blame the breather hose coming off the valve cover because it dumps oily blow-by gases directly into the carb, and apparently these gases also muck up the inner surfaces of the air cleaner element.
So I blocked the stock breather passage on top of the air cleaner lid, and I added a copper pipe and elbow on the valve cover port, rear-facing.
You can see the modification just to the right of center in the photo.
Spoiler
It's an easy mod to undo before smog inspection.
Any thoughts/recommendations?
Last edited by MichaelKLerner; Jul 26, 2020 at 01:43 PM.
Reason: delete spoiler
Install a catch can in between the two connections to catch the oil. You do want that hooked up as it will help create a negative air pressure in the crank case. This helps keep oil from leaking out of the seals and should help the rings to seal.
You either have a PCV problem or an excessive blow-by problem.
MY 1987 22R (all stock) doesn't cover the air cleaner element with oil. All I see is a small amount of oil residue right at the end of the metal tube where the tube enters the air cleaner housing.
This series of engine has an oil baffle designed into the valve cover, if this is clogged with baked on oil deposits it's not going to work as well as it should. It's a bit labor intensive to drill out the peened over material then drill and tap for screws, but it's the only solution really (you can of course add a catch can as mentioned, but this doesn't unclog your baffle). You'll need a new gasket and thread lock for piece of mind..
As mentioned you can get a genuine Toyota PCV valve, they are sub ten dollars from the dealership, this lets you know when it was changed (its a maintenance item), that it is the specified design, and functional.
This line you plugged/altered is the PCV system breather port, it has two functions.
A) when the PCV valve is open it draws fresh air into the crankcase.
B) when the PCV valve is closed it allows pressure to escape the crankcase.
What you are seeing is either a faulty (out of spec) valve, or excessive blow by that is overloading the PCV valves ability to evacuate the crankcase.
In the short term the lowest cost solution is to put an off the shelf filter on the end of your modified breather port to keep it from sucking in dirt and dust.
Last edited by Co_94_PU; Jul 26, 2020 at 02:49 PM.
This is 1 of the dumbest things I have ever done -- forgetting the PCV valve. It is one of the first things I learned to check when working on cars as a kid, and I never before found one that actually needed replacement, but I used to remove them and clean them assiduously.
The PCV Valve was indeed gummed up. I finally extricated it from the valve cover. The grommet was baked hard and wouldn't give at all. So I destroyed it. And my next question is, do new PCV valves come with new grommets?
CO_ 94_PU: This is awesome. Thank you so much. If replacing the PCV valve fixes the problem, I won't worry about it but this is good information. But if replacing the PCV doesn't cure, I will definitely pull the valve cover and do whatever is needed.
This is 1 of the dumbest things I have ever done -- forgetting the PCV valve. It is one of the first things I learned to check when working on cars as a kid, and I never before found one that actually needed replacement, but I used to remove them and clean them assiduously.
The PCV Valve was indeed gummed up. I finally extricated it from the valve cover. The grommet was baked hard and wouldn't give at all. So I destroyed it. And my next question is, do new PCV valves come with new grommets?
Almost certainly none of us have a test system that can check PCV valves! Yeah you can shake it and see if it's stuck. Yes you can also see if it only passes air in one direction. What you can not check is how the spring fatigue has effected it's switch point, or how much volume it passes (flow rate)..
While wouldn't say change it every oil change, probably with sparkplugs or yearly maintenance isn't a big added expense.
Originally Posted by MichaelKLerner
CO_ 94_PU: This is awesome. Thank you so much. If replacing the PCV valve fixes the problem, I won't worry about it but this is good information. But if replacing the PCV doesn't cure, I will definitely pull the valve cover and do whatever is needed.
It's something to put on your list for the next valve adjustment regardless, if you've got signs of baked on oil on the head or valve cover it's safe to say you have some restriction in the baffle chambers also.
Almost certainly none of us have a test system that can check PCV valves! Yeah you can shake it and see if it's stuck. Yes you can also see if it only passes air in one direction. What you can not check is how the spring fatigue has effected it's switch point, or how much volume it passes (flow rate)..
While wouldn't say change it every oil change, probably with sparkplugs or yearly maintenance isn't a big added expense.
It's something to put on your list for the next valve adjustment regardless, if you've got signs of baked on oil on the head or valve cover it's safe to say you have some restriction in the baffle chambers also.
Jul 26, 2020 | 01:42 PM
