Re: Can you run your engine without a water intake
As mentioned, the only issue with a short run will be the impeller. You can easily pull the impeller and run the engine for a short period of time. Depending on the seal type on your raw water pump, you may get marginally shorter life out of it but it is a very small concern.
The other way you can do it is to run a continuous loop system where you feed the exhaust water back in to your bucket. The concern here is that you don't want to melt the bucket.
With either of these methods, the key is that you can only do short runs. If you run for too long, things are going to get hot and there are a few risks. One risk is that you start creating steam in your cooling passages which is bad as steam is 600 times less dense than the water it replaces. If you are at the point of creating steam, you are also getting to the point where you damage the engine from overheating. Another major concern would be that your exhaust hose will be hotter if it normally has water going through it.
I think that you first need to justify why you want to run the engine regularly. A properly laid up engine will be fine for 2 years.