[madmonkey]

I have a 1966 289 2V, original California car equipped with the smog pump and everything. I was wondering what is the hose that connects to the back of the air cleaner assembly for? I know it has something to do with the smog pump and stuff just don't know the details of it's purpose or how it works. If I was to get the HiPo style air cleaner where would this hose go?

[Bob A]

I'm thinking it might go to the PVC valve on the right valve cover. You might want to purchase a vacuum diagram manual from one of the Mustang vendors. Hopefully somebody with knowledge will chime in. GOOD LUCK

[Al Newman]

Monkey,
The hose you refer to should be attached to the oil filler cap on the drivr's side of the engine. It merely directs engine blow-by back into the carburetor. The HiPo air cleaner has a knock-out on the underside with an attachable nose that the hose can fit onto. This is California car only.
Best,
Al Newman

[madmonkey]

This is a different hose. There is a hose on the front of the air cleaner assembly that goes to the oil filler cap. There is a hose from the PCV on the passenger side valve cover that goes to the carb spacer. This hose is on the back of the air cleaner it is coming from a blue hat like device and plugs into the the back of the air cleaner assembly. Other hoses route from the smog pump to this device. I'll post a picture to clarify what im talking about soon.

[madmonkey]

i just figured out what it is called. It is called the Thermactor Air System which just pumps air into the exhaust ports fully burning any gases that were not completely combusted in the combustion chambers reducing carbon monoxide and other hydro carbons. The blue hat looking device is the backfire suppressor. When you snap shut the throttle quickly a bunch of unburned fuel will have been dumped into the cylinders if the smog pump pumped air into the exhaust ports then you would have a backfire. The hose is the dump hose, where excess air from the smog pump gets dumped back into the air cleaner assembly. So if i got the HiPo style cleaner would i just remove this hose so the excess dumped air just gets released into the engine compartment?


Here is a link a found about the TAC system
http://www.autozone.com/az/cds/en_us...rInfoPages.htm

[kenton_90]

I dont think the thermactor sytsem was put on cars until 67 is your engine original?

[madmonkey]

yes it is an original engine, my grandpa bought it used in 1968 and rebuilt the engine about 20,000 miles ago. they were put on in california starting in 1966 from what i've read.

[madmonkey]

anyway, does anyone know what to do with this hose if i get the HIPO air cleaner????

[Bob A]

Why not remove the air pump and everything related set it a side in case you what to bring it back to stock and then cap all openings. Back then Calif. was the only state were these cars were equiped with air pumps.