6.5 non turbo intake gasket

[TexF18]

Order a new set of intake gaskets from hummer parts guy and have a question about the silver cover. New gasket doesn't have it. Is this a problem or is it just a parts revision

 

[Mogman]

Those are the exhaust to intake manifold heat ports, IIRC there is no matching port in the manifold so the exhaust has nowhere to go anyway so you should be good.
I will run out and check a manifold

 

[Mogman]

Yes you are good, no ports in the intake, just blocks it off anyway.
This is left over from the old carburated gasser days, they would have a thermally controlled butterfly valve in one of the exhaust manifold discharge ports to cause an imbalance in the exhaust flow so it would cause some of the exhaust to pass from one head to the other through the intake manifold to pre-heat the intake, I have never seen this on any diesel so I am not sure why it carried over to the diesel head...

 

[Mogman]

This is called the heat riser, it would be where the exhaust pipe would connect to the manifold on one side, when cold and closed it would cause the exhaust to divert through the intake manifold from one head to the other...

 

[mgFray]

View attachment 865591
This is called the heat riser, it would be where the exhaust pipe would connect to the manifold on one side, when cold and closed it would cause the exhaust to divert through the intake manifold from one head to the other...

My '67 Jeepster with a Buick v6 has one of those. As was mentioned, when it's cold it causes some additional back pressure to force hot exhaust to go up into the intake and through the heat activated choke.

Not something I would expect on a diesel.

 

[Sigi]

My 64 Corvette had this heat riser valve on the passenger side. Probably a good idea when you commute in very low temperatures. Downside is it will rust out the passenger side muffler quickly when you do short trips due to moisture accumulation. Easy to remove and replace with the fuel injection riser in temperate climates.