It's been a lot of years now since I parted with MY 1971 Pinto 2.0L/4-speed sedan, so I don't remember, but according to at least one reference I have here, the OEM type, (typical stamped steel 2 piece painted sheet metal) air filter housing/air cleaner DID have 4 wingnuts holding it on, so it may work with the carb that is on there now-if you want or need one, and can find it.
The OEM carb should be a 5200 series, Holley licensed Weber, progressive 2 barrel. If it has the four air cleaner studs, and 2 choke plates on a common shaft and the choke plates themselves are round cornered squares, that's probably what is there.
For several years the choke on this carb, (when used on the Pinto), was heated by a choke cover with a water passage having 2 fairly large diameter
coolant hose connections. So, if you happen to have an inexplicable connection between 2heater hoses, for example, the choke heater cap may have been eliminated and the choke may have been altered to use a manual choke. A lot of people have done this over the years, to "clean up" the coolant hose routing when doing some engine dress up work, like using an aftermarket air cleaner.
The OEM Air cleaner housing would also have had a hose connection, with THAT hose running to the charcoal cannister. The PCV valve should be at the end of the hose that goes from the intake manifold to the oil separator. There should be a vacuum hose coming from the intake manifold to the DUAL diaphragm distributor (2hose connections), and one coming FROM the distributor, going to the base of the carb.
As far as the oil filler/breather cap goes, the engine was a closed PCV system, so
the OEM one should have had a connection for a rubber hose that went from the
cap either directly to the intake manifold, or to a connection on the OEM air cleaner. That cap may not be the easiest thing to find, as you are noticing. This may be because the 2.0L engine was one of the first that Ford brought in from Ford of Germany, so a lot of the peripheral engine related was different from more readily available stock items being used on the rest of the Ford line at the time. Like the 4 stud air cleaner.
IMHO, this is a VERY good carb. probably the best combination of features, simplicity, performance and reliability that I've come across on any Ford
OEM carb from that era.
I bought mine from my brother with 140,000 miles, (he bought it with about 40,000), ran it up to 201 before selling it, and as far as I know, the only time that the carb was rebuilt was around 180,000 miles, when I did it. I was doing some long distance vacation and camping driving then, and didn't want to take a chance on something finally going wrong on the road, so I basically did it as preventative maintenance.
If you've mostly worked on Fiestas and later Ford cars, watch out for a mixture of Metric and SAE fasteners being used on this car.Much of the engine related stuff will be metric, and the rest of the car will be almost all SAE, but the possibility of some Bozo using a SAE fastener where a metric one belongs (and vice versa) is always there, and was MUCH more prone to happen when this car ws newer,
so pay close attention and be on the lookout for cross threading when doing any disassembly/reassembly work. Someone ahead of you may not have been as watchful.
