Manifold insulator question (1 Viewer)

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I'm working on changing out my ps and smog pump when i noticed that my hot air intake hose disconnected from the air cleaner. As I inspected further, I notice the other end of the hose was attached to a J pipe pointing to the manifold but not attached. I didn't know exactly what it was until I researched further here and noticed that the J pipe is all that's left to the manifold insulator.

Question - For those in smog states and don't have the insulator, what do you do? Diagram attached for reference. My 60 seemed to run fine with the set up of just pointing the J pipe towards the manifold.

exhaust insulator.JPG
 
Joined
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All that does is pull hot air off of the exhaust to help the engine warm up in cold conditions. I don't think it matters too much unless you are in a very cold climate and trying to improve engine warm up by any means possible. I am in vermont and removed mine as it was not in good shape. If you decide you need it you can use any flexible heat resistant hose that fits.

Even what you currently have is still probably good enough. Its not part of the vacuum manifold and its just there to help the air cleaner pull warm air from that area when the valve flips in the air cleaner neck.
 

DFXR

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A crappy pic but tried to highlight the hose and the J pipe at the end not attached to the manifold.


Here's that hose:


A new one makes things easier when you're taking the air filter assembly off and on. You need some kind of hose there to pass the visual here in CA.

The metal insulator assembly is harder to come by. You might find a used one at cruiser parts or from someone desmogging in the classifieds.

But there are 2 mounting holes on the insulator - your upper one looks broken but if the lower one down to the right is still OK yours should hold with a tight bolt in there. There's not any pressure in there - it just needs to stay in place. The most action it ever sees is someone taking the air filter assembly off and on.

If you pull the rubber hose going to the air rail off and out of the way, and then pull the existing hot air tube off, you should be able to get at the insulator and see if the lower hole will work. Sometimes it's easier to put a stud in the manifold and then place the insulator on it, than it is to blind-thread a bolt in there.
 
Joined
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Messages
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San Francisco Bay Area
All that does is pull hot air off of the exhaust to help the engine warm up in cold conditions. I don't think it matters too much unless you are in a very cold climate and trying to improve engine warm up by any means possible. I am in vermont and removed mine as it was not in good shape. If you decide you need it you can use any flexible heat resistant hose that fits.

Even what you currently have is still probably good enough. Its not part of the vacuum manifold and its just there to help the air cleaner pull warm air from that area when the valve flips in the air cleaner neck.
We don't get anywhere as cold as Vermont in these parts unless we head up to the Sierra. Good to know though. Thanks.
 
Joined
May 14, 2018
Messages
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Here's that hose:


A new one makes things easier when you're taking the air filter assembly off and on. You need some kind of hose there to pass the visual here in CA.

The metal insulator assembly is harder to come by. You might find a used one at cruiser parts or from someone desmogging in the classifieds.

But there are 2 mounting holes on the insulator - your upper one looks broken but if the lower one down to the right is still OK yours should hold with a tight bolt in there. There's not any pressure in there - it just needs to stay in place. The most action it ever sees is someone taking the air filter assembly off and on.

If you pull the rubber hose going to the air rail off and out of the way, and then pull the existing hot air tube off, you should be able to get at the insulator and see if the lower hole will work. Sometimes it's easier to put a stud in the manifold and then place the insulator on it, than it is to blind-thread a bolt in there.
I passed smog last year with no issues. I don't know if it was bolted on the lower mounting holes. There's enough still there where I should be able to mount it back on. Thanks.
 

OSS

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All that's required to pass the visual inspection at a CA smog test is the hose clamped to the air cleaner neck and pointed next to the exhaust manifold. The original shroud/duct that cupped around the manifold shoulder was made of fiberous material (likely containing asbestos) and it dissolves with age. There never was a nice metal shroud like found on the earlier cruisers.

The hot air intake system isn't just for warming up. It keeps the intake air charge at the optimum temperature whenever the outside air is cold. It's a good thing to keep functional even if smog tests aren't required.
 

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