Can you ID this air cleaner?

[cortcomp]

This came with my 66 C10. The truck has the AIR system (from california) but most of the pieces are missing, and i was considering scrounging and putting it back on. This doesn't look like the air cleaner that i see on most trucks or in manuals, but i didn't know if it was different because it was with an A.I.R. truck? It does have a big nipple out of the bottom that the ugly PCV looking hose from the rear of the motor seems to go to.

Thanks!

[markeb01]

I’m not an expert on these air cleaners but it looks to me like an early-mid 60’s stock 4 barrel air cleaner, the older type the fits the smaller 4GC carb opening in the base plate. Most of the GM lines used these during that period, and they were as common as radiator caps at one time. Here’s a two barrel example on Google Images which generally had the smaller snorkel:



What you have could certainly have been original to your truck, or could just as easily have been the result of swapping parts. The lid with the larger snorkel could easily be swapped on a two barrel carb by simply switching the lower plate which I did routinely back then.

There was a tremendous amount of non-standardized variation in factory smog setups between 1964 and 1968, especially if you lived in California. In California many 66 and some 67 models only came with a smog valve. In 1967 AIR (Air Injection Reaction) smog pumps became mandatory on cars that came with them installed at the factory. Many owners pulled them off and installed pipe plugs in the exhaust manifolds.

Once smog equipment inspections came along, cars that showed up with pipe plugs failed the inspection and owners were required to reinstall the entire system (usually at significant expense since they had thrown everything away). Smarter owners simply replaced the exhaust manifolds with earlier versions having no smog ports. Those cars easily passed inspection because they “apparently” had not originally come with air pumps!

Before the manufacturers and national smog laws came to agreement, California legislated a novel way to get thousands of older cars off the road by destroying their engines. This was achieved by requiring the installation of add-on universal smog kits.

The kits normally included:

A sealed breather cap with a hose connection.
A length of large 1” diameter hose.
1” diameter chunk of brass or steel bottle brush, to be used as a backfire flame arrestor.
Assorted T fittings.
A pound-in intake manifold/hose adapter.

The worst damage was caused when the intake manifold had a ½” hole drilled in it and the lead plug/adapter was pounded in with a hammer. A piece of hose was pushed on the adapter and connected to the new (sealed) breather cap. The greatest amount of damage was caused when most shops did not bother removing the intake manifold for drilling the hole, dropping all the cast iron filings right into the engine destroying all sorts of bearing surfaces in a very short period of time – ruining the engine, which routinely led to junking the car. I’m very familiar with these kits because I installed several during my youth and they were a major pain, because I always removed the intake manifold before drilling.

The second problem being the smog valve had not been developed yet so the hole in the manifold represented a huge vacuum leak causing the engine to run very poorly, another reason owners quickly grew to hate smog equipment.

The road draft tube was removed and replaced with an adapter connecting a 1” hose to the air cleaner. The chunk of wire brush was crammed in the middle of the hose to act as a flame arrestor in case the engine backfired. This was supposed to stop the flame from travelling all the way to the crankcase igniting the fumes and blowing up the engine.

I mention this to explain there was a long period of confusion, anger, frustration, and lawsuits over ruined cars during this period. Also there were so many rule and technology changes during this period many owners and smog inspectors weren’t really sure about what was legal. This confusion went away once the PCV (Positive Crankcase Ventilation) valve became standard equipment.

Unless you want the smog pump system for restoration purposes, it’s unlikely you would need it even in California, so long as the exhaust manifolds don’t have provision for the air injection manifolds. From my experience these didn’t become mandatory until the 1968 models.

If you still have the road draft tube at the rear of your engine, you will benefit by eliminating it and installing a smog valve between the adapter that bolts into the road draft tube outlet and the main carb vacuum opening. This keeps the crankcase clean and free of sludge. This requires either an early intake manifold with a breather/fill pipe at the front, or valve covers with breathers, since the crankcase needs a source of fresh air. In later engines this ventilation air was supplied from the air cleaner connection to a sealed breather connection at the valve cover or the oil fill tube.

The problem with this arrangement in earlier versions (like yours) is the complete lack of filtering at the air cleaner base which allows crankcase/oil fumes to foul the carburetor. Later versions added a filter to the air cleaner base to minimize the crud being ingested by the carb. Hope something here helps.

[cortcomp]

What a wealth of information! It is a 4bbl 4gc, and the previous owner just cut the air tubes and crimped them shut, leaving me 8 tiny exhaust leaks -_- Anyway, after thinking more about it, i'm just not going to bother with it. The main reason, besides cost and annoyances, is that it covers the valve covers too much with the hoses, which really shows a lot of color in a detailed engine bay. I would still like to find the right air cleaner, i'm guessing this came off of a car or something, and i don't see anything like it on other trucks. Also confused about the holes in the back/one side. They're too nice for drilling, so they must have been stamped that way, i don't know what would connect there with that pattern, on any car.

I do have the non-breather oil fillter cap, and again, some kind of PCV hose going to the back of the motor somewhere to get vent gasses from somewhere. When i pull it to clean and re-gasket everything, and paint, etc, i guess i'll get to the bottom of some of these details.

[Vernski]

If the air cleaner has any part #'s on it you could google for it or take the #'s to a parts house and have them check GM #'s ,it does look like GM. Also you could run the #'s on the engine block and see what year the engine was suppose to be in then go from there...Vernski

[cortcomp]

The engine is code YC if i recall, which is correct for my '66 327 with A.I.R., the top does look almost the same as the picture above. I'll try and find some partnumbers tonight, maybe i'll get lucky! If i can sell it to someone who needs it, i can keep an eye out for one that's right for my truck.

[SCOTI]

I have the same air cleaner lid/set-up.

Mine was off of a mid 60's GM intermediate w/a 2bbl base. The truck units had the longer 'snorkel' which I didn't care for. The car units I'd seen had the shorter oval snorkel.

I modified a later 4bbl base & use a newer filter that's the same size as what a 73-? C10 would utilze in an emission type application (sealed, thermo type air cleaner housing).