Extra port on Air Cleaner Assembly?

[Source3]

I am replacing hoses on a 1972 FJ40 with an F engine and cannot figure out what the extra port on the air cleaner assembly is for (see yellow circle in the below photo); I have looked in the Haynes manual and searched the forums with no luck. I did find a photo of an FJ55 with the same assembly, no hose was attached. I am worried that I am letting unfiltered air into the carb.

Was it to allow warm air to enter during the cold season. If so, what (or where) does it connect to.

I am new to the restoration process...please be kind in your explanations.

Thanks,
Source3

 

[Coolerman]

Only pic I could fine of a 1972 with that style air cleaner has the port just blocked off. I found a 1973 pic that is also blocked off. Maybe it's a precursor to emissions stuff?

 

[donny paradise]

That port is part of the smog related crap that it use to be equipped with Plug it off!

 

[Source3]

The emission statements make sense, After all, I do have a stamp underneath the hood that references the California 1973 emission standards. Maybe Toyota was getting ready for the 1973 standards when they rolled out this vehicle with a production date of 9/72.

I will block off. Thanks for the clarifications.

 

[Downey]

I may be way off base here because it's been 1,000 years since I owned a 6 cyl. Landcruiser. In the photo I do see the PCV Valve that vents the crank case, but I see no provision on the valve cover to vent the top end. Wouldn't it be prudent to weld a breather fitting onto the valve cover, then install a connector hose between valve cover and fitting on air cleaner. This would let your engine burn-off all the oily pressure that builds-up under the valve cover.

 

[Coolerman]

That what the red circled hose does. There is a nipple on the side of the valve cover and the L shaped hose connects that nipple, to the nipple on the air cleaner.

 

[Tools R Us]

IIRC that is where the smog pump intake connects.

 

[Pighead]

I may be way off base here

Yup.

IIRC that is where the smog pump intake connects.

Yup.

 

[bsmith123]

PCV hoses

I may be way off base here because it's been 1,000 years since I owned a 6 cyl. Landcruiser. In the photo I do see the PCV Valve that vents the crank case, but I see no provision on the valve cover to vent the top end. Wouldn't it be prudent to weld a breather fitting onto the valve cover, then install a connector hose between valve cover and fitting on air cleaner. This would let your engine burn-off all the oily pressure that builds-up under the valve cover.

Jim,

Just to clarify the two hoses--The PCV vents to the manifold taking the crankcase pressure away and the top one from the air cleaner is just routing fresh air back in to replace it.

Air venting out the top hose usually means a clogged PCV (check valve), Ring Blowby, or the PCV installed the wrong way round shutting off the vent.

 

[FineWynsFJ40]

I have one on the side like that, and one on the bottom. For me, the one on the bottom is plugged and the one on the side goes to the valve cover. That is all.

Brian

 

[Coolerman]

IIRC that is where the smog pump intake connects.

Whats smog, and why would you pump it?