'65 327/350 overheating at idle

[Duke W.]

Re: '65 327/350 overheating at idle

I don't think anyone mentioned checking the ignition map, especially the vacuum advance for proper specification and operation.

An improper spec, malfunctioning,removed or disconnected vacuum advance is probably the most common cause of idle and low speed overheating.

Duke

[Doug Flaten]

Re: '65 327/350 overheating at idle

As Dave and Duke said, I would check the timing and vacuum advance. Insufficient vacuum advance at idle may cause your overheating. At highway speeds, you have two things going for you. More air flow, and the centrifugal advance has helped to advance the timing. Armed with info from this board, I was able to solve an overheating problem on my Mustang that had a faulty vacuum advance. While mapping the timing curve on another car, I learned it does not take long for the engine to get hot while idling with the vacuum advance disconnected.

[Ed Jennings]

Re: '65 327/350 overheating at idle

Agree. He mentioned that the timing was set ok, but did not indicate that the vacuum advance at idle had been verified. That is the one thing that would definately cause overheating at idle and not necessarily show up anywhere else. The vacuum advance may even be working, but not adding full advance at idle vacuum.

[Joe C.]

Look At My First Post, Above

The most important question was never answered. Some folks have different definitions of "overheating".
If you look closely, I think that the "flowchart" I have provided, gives a good course of action.

PS FOR DON MANCINI:. If your carb has an electric choke, and it is working, then please leave it alone. You obviously do not have your original carb installed. If you are looking for "correctness", then you will need the 2818, and the aforementioned heat pipe. The 1966 version of your engine used a choke spring and stove which live in the intake manifold (different than the 1965 manifold), and eliminated the external heat pipe out the pass side exhaust mani.