1981 Deville - What part is this?

[adam-newton]

Hello all,

Just trying to identify this part on my 1981 Cadillac Deville. I have identified it as number 2 in the photo attached. It is a non serviceable diaphragm currently leaking coolant.

Thanks in advance for your help.

Adam

[adam-newton]

Pic now attached lol

[smokuspollutus]

That's an AIR diverter valve. To supply oxygen to your exhaust manifolds and catalytic converter to lower emissions. Somebody really screwed up if its leaking coolant! Get that heater hose off of there!

[adam-newton]

Thanks.

So section 1 has air lines to it. Section 2 has hot water lines on it.

Are you saying that's not right? Does anyone have a diagram or is familiar with the 864 V8 set up.

Thanks

[adam-newton]

In related news. We fired up the car today. Air pimp had ceased. Pulled it off. It's full of coolant. Something ain't right here. Help wanted.

[The Tassie Devil(le)]

That isn't good, as there is the possibility that you could have backwards flowing of the coolant into the Exhaust system, or even the Exhaust Ports in the Cylinder Heads.

Bruce.

[smokuspollutus]

Holy moly. Maybe this car was a mosquito fogger in a past life?

The heater hoses should flow from the cylinder head to the heater core, and then back to the return at the radiator.

The Diverter valve should have an input from the smog pump, and 3 outputs-a stub hose to the air cleaner, a hose to the check valve attached to a pipe leading to the catalytic converter, and a hose to the check valve attached to the exhaust AIR distribution block. And a vacuum supply line.

Neither has anything to do with the other. Good luck!

[adam-newton]

Thanks guys!

This has all been incredibly helpful.

@smokuspollutus
Thanks so much. Sounds self-explanatory. Just in case, do you have any diagrams for this and do you know of any guru's in Australia for these cars that I can get in contact with?

Thanks so much.

[adam-newton]

This has now been solved. Thanks so much for your help.

More info here

1981 Cadillac Vacuum and hot water configurations