I am considering installing a calorifier to the above engine which is keel cooled with a traditional hand lever to control the temperature. Can you advise me where I should make the in and out connections to the calorifier, and if you consider that the flow through the calorifier needs to be pump assisted. Just found your site, very interesting.
To be sure about your question I would need a diagram of your system, because I have never heard about manual control of engine temperature before.
Let us assume that your engine has a centrifugally pumped system and the lever gradually opens or closes the flow to the skin tank/keel cooler. In this configuration I would expect to find a smallish bypass pipe that allows the water to keep circulating with your valve closed, if you have this, simply connect the calorifier in place of this pipe.
Otherwise Tee off from the engine side of the valve to the calorifier and then back into the hose returning to the engine from the keel cooler/skin tank.
Both of these options will give a slower warm up, which might be prolonged on a large engine running at very low load, however as soon as the calorifier is up to temperature the engine will operate as normal. Drawing any hot water off may cause a drop in engine temperature.
As I have never installed a calorifier that is higher than the engine I can not answer your second question with any certainty. In theory the engine water pump should be capable of moving the water, but you really need to know the head that it will pump to with the engine at idle. If the pump is a “jabsco” type pump it should be fine.
My main concern is that there would appear to be no way of venting air from the calorifier and without work relating to the cooling header tank, I fear it will constantly airlock. Also the slightest air leak into the calorifier circuit would result in coolant being wasted via the header tank overflow (unless the tank is higher than the top of the calorifier coil).
Rather than ask me I would advise that you talk to someone who is well known for dealing with old Lister Engines, they should have more specific knowledge.
