Im going to snap some pics of mine first thing tomorrow. Im very confused now. I dont know if the valve cover is different, or the air cleaner. Im assuming they were year model, but Im guessing you guys could probably tell me.

Also, does anyone have a choke linkage from the stock Carter YFA 1 bbl? Mine doesnt have one, and its starting to get cold here.

 

The oil cap doesn't vent because you don't want it sucking dirt into the oil. If it's building up pressure and blowing out the dipstick then you have too much pressure meaning the PCV valve is not working. Test the valve closes if you blow on the hose, but opens if you suck on the hose. The whole point of the PCV valve is to block pressure from the intake from going into the valve cover while allowing the vacuum of the intake to suck any pressure out of the valve cover and crankcase. In a system that does not have a PCV valve on both sides you would have a PCV valve on one side that is connected to vacuum on the engine side of the butterfly valve of the carb or throttle body, the other valve cover would have a port that's connected to the intake on the air cleaner side of the butterfly valve of the carburetor or throttle body. That way The vacuum produced by the engine sucks any pressure out of the valve cover and any air that comes into the system comes in through the other side from a filtered port through your air cleaner. Adding a breather to the other side may allow pressure to get out through the breather but that's supposed to be where air is coming in not going out so while it may alleviate the symptom you're just covering up another problem. Make sure that PCV valve is working. If the PCV valve is working properly then your engine is producing way too much pressure inside the crankcase. That would mean you either have a cracked head or block, blown head gasket, way too much blow-by on the rings of one or more cylinders, or valve seats are not sealing and blowing exhaust into the intake back through the broken PCV and out wherever it can, like the rear main or oil tube. combustion gas test kit are only $10 to confirm combustion gas leaking into coolant or crank case. if you can get a legitimate leak down tester to check each cylinder I would recommend it. If you have excess leaking on a cylinder going out intake or exhaust, gargle the leaking valve with pb blaster, put the handle of a hammer on the top of the valve where the rocker sits and give it a little tap/slap to jar it open momentarily a few times to see if it blasts out any junk blocking the valve from sealing. When it gets a good seal it will stop moving when you tap it, you can feel and hear the difference. If the leak down tester showed it's good see if your blow out problem is gone. If you still have blow out, you may have to pull the heads to lap the valves, unless your skilled enough to do it without pulling the heads (I've only seen it done once, they rotated the piston to top of the cylinder, depressed the valve spring, pulled the clips and spring, gripped the valve in drill jaws and went through the exhaust port with an acid brush to apply lapping compound than reassembled for the final race), but at that point you may decide to either rebuild or live with it till it dies...