71 C10 4.1L L6 air cleaner vacuum pot replacement?

[trevarthan]

Hello,

I've got a 71 C10 4.1L (250) L6 with a bad vacuum pot on the air cleaner snoot:



I can manually actuate the flapper with the air cleaner removed by pushing fairly hard from the bottom where the exhaust gas would normally come in. However, the pot itself won't hold vacuum and doesn't actuate the flapper inside the snoot.

Where might I buy a replacement for this item or a replacement air cleaner assembly with an included pot? I'm having trouble with my search fu.

Thanks!

[franken]

A quick google suggests not so easy.

https://www.google.com/search?client...71.tpJaubxlICM

I'd guess that allows for more choke (why), or heated air coming up from the exhaust manifold to help cold idle and faster warmup. Assuming the latter, you also need to fix the flapper after the exhaust manifold and the tinfoil flexhose, which might be harder. BTW, the flapper in the exhaust manifold typically locks up--forever.
I'd get rid of all of it and make the choke work. The AC flapper has a few spot welds holding it on and a small hole you can metalwork away. Just an opinion. Unless you can figure out a way to replace the rubber diaphragm.
But the question remains, with vacuum, the air cleaner flapper stays closed? It should open.

[trevarthan]

Originally Posted by franken

I'd guess that allows for more choke (why), or heated air coming up from the exhaust manifold to help cold idle and faster warmup. Assuming the latter, you also need to fix the flapper after the exhaust manifold and the tinfoil flexhose, which might be harder.

Yes, my understanding is that it is the latter. There is a thermostat mounted inside the air cleaner. When it gets hot enough it stops the flow of vacuum to the actuator on the snoot.

My exhaust hose is not tinfoil btw:

Originally Posted by franken

BTW, the flapper in the exhaust manifold typically locks up--forever.

Mine isn't locked up. The spring is broken, but it rotates freely.

Originally Posted by franken

I'd get rid of all of it and make the choke work.

I have a temperature controlled auto choke. It is working, for now at least.

Originally Posted by franken

The AC flapper has a few spot welds holding it on and a small hole you can metalwork away. Just an opinion. Unless you can figure out a way to replace the rubber diaphragm.
But the question remains, with vacuum, the air cleaner flapper stays closed? It should open.

Sorry, I described this, but it's hard to describe with words. I'll try some photos. Mine is open by default:



I have to push up pretty hard from the exhaust side to close it:



Applying vacuum to the pot on top does nothing. The pot does not hold vacuum and does not close the flap.

[Steeveedee]

I did a quick look-around and don't see those readily available, except for maybe buying the whole housing. That seems a bit expensive and who's to say how long that diaphragm will last? Depending on the average temperatures in your area, maybe you can leave it inoperative. It will, however, give better mileage if it works, because the choke will be open sooner, since the air drawn though the stove pipe will heat the carburetor. If the heat riser valve in the manifold stays open, the engine will also warm up more slowly. On a 6-cyl, I think you have to buy the whole manifold, but I could be wrong.

[Grumpy old man]

Your in Chattanooga , As long as it's open leave it alone .