Easier PCV Valve Reroute - Newbie question

[estoltman]

Does the PCV Valve have to be routed to the carb base?

Couldn't you just plug everything except for the PCV Valve and let it vent to the outside air?

No hose from air intake to the Valve Cover either - plug those as well.

Just trying to keep the engine plain and simple.

Any issues with this?

 

[Coolerman]

Well.... environmental issues aside?

Yes, you can vent the PVC to atmosphere, but if you don't put some kind of catch filter on it you will have an oily mist that settles on things attracting dirt.

The valve cover should also be vented, but may not be as critical. Jim C could better answer that. If you do this, plug the carb base port, and the air cleaner port for sure.

 

[grant5127]

A working PCV system is needed to maintain a healthy engine life.....(reduces HCs in the crank case "sludge")... it needs to suck from center manifold vacuum source whether it be carb base or manifold.....you can source aftermarket valve cover inlet filters that are suitable and add a bit of a snazzy look as well.....

 

[estoltman]

OK - thanks. I guess I could put an inline filter/catch can to reduce the amount of oil going back into the intake. I read some articles on that here and elsewhere. thanks Again

 

[MoCoNative]

Part of the reason you direct those vents to the manifold is to get a little suction on them, so you are actively pulling gases and trapped water vapor out of the engine. Also having them connected to the manifold and or aircleaner, it assures the system is sealed from foreign contaminants. As far as simplifying the engine, these two connections are the least of your worries. Every engine built will have these connections, even new vehicles still have similar systems. I have never seen that residue coming from the PVC is an issue on a good running F series engine, they just are not that high tech that a little sludge injected in the intake will adversly effect the performance of the engine.

And if you are taking smog stuff off, know that some of that really should stay, as it controls other critical systems, not directly tied simply smog emmisions. Your distributor for example needs the vacuum lines to it for proper operation and timing advancement. Charcoal canister is another system that should stay intact to avoid vapors in the cab and under the hood.

 

[estoltman]

Yep - I have a vacuum line to the distributor.

I took charcoal canister off (and plugged the line from the fuel tank). Will the fumes still be a problem? If so, I can reattach.

Do the canisters ever go bad? I assume as long as there is airflow thru the canister, it's okay?

 

[MoCoNative]

I would search a bit if you didn't on good desmog techniques. What I have found is that when everything is present on a Land Cruiser, emmision wise, they run very well, and the theoried loss of power is very small.

From my experience, I have a 73, the original owner ripped the smog stuff off in about 73. My dad got it in 77, and drove it many years, and then we resotred it for me. I have had constant troubles with getting it dialed in just right. On the other hand, I have a stock 60 series, 225,000 miles, and it runs flawlessly. The emmisions system is really an early approach at computer control of the engine.

A good desmog can be done, and it greatly simplifies the system for sure. I have done that on my 40, but I have also spent years researching each system and tracking down parts that will help me, not hinder me.

One system is the charcoal canister. The fuel tank on a 40 is vented in three locations. These are the hard lines embedded in the top of the tank. They assure, that no matter the angle of the vehicle, the gas tank gets proper ventilation. As you consume gas, you must replace it with air. From these vents, they go to a plastic container behind the passenger seat, on the wall. This container accounts for expansion of the gas and vapors in the tank, and settles out liquids, so they run back in the tank. From there the vapors go to the charcoal canister under the hood. The charcoal captures gas fumes, to later be burned in the engine. The emmisions computer dictates when these vapors are burned, determined by operation conditions of the engine. This portion can be simplified some, but simply hooking it up to direct vacuum may not be completely correct.

Without all of this, I had to use a vented gas cap. Prior to that, my dad just messed with the seal on the cap, so it wouldn't seal. On hot days, if the rig had a full tank, and was sitting leaning towards the passenger side, it would run gas right out the filler. In extreme off camber situations, it would run gas out. Not to mention the fumes that would get in the cab, as the tank tried to expand, and pushed gas vapors past the sending unit gasket and hose clamps.

Canister should last, you can run some compressed air through them to help clean them out and rejuvinate the charcoal.

 

[estoltman]

Thanks. I will blow some compressed air thru-it.

BTW - when I got my FJ40, it was a CA model with lot's of extra smog stuff on it, including the quirky CA exhaust manifold that was ready to fall apart at any minute (header now).

So, I agree some of the emissions stuff is needed (I'm learning), but the EGR system, smog pump, and air blower are gone for good.

To be honest, I've desmogged and performance built a bunch of different toyota and japanese engines in the 80's (carb and EFI), but never dorked with the charcaol canister or PCV system. So OOPS! on my part on my FJ40

Thanks for all the help!!!!!

 

[MoCoNative]

Just trying to save you some headaches. I'm a believer in the systems if they are working. My 60 is really one of the best running vehicles I have ever driven. It has issues of course, and I'm very lucky that all the smog stuff appears to still be operating, but engine wise it never faulters.

CA emmisions are intense though. Some real overkill there.