I’ve been running motors dry ever since I’ve been running motors. Without damage. It is true that when they came out with multiple carburetors, OMC said not to run them dry because one would run out of fuel before the others. OK those guys made a lot more money that I did but still I say BS. If running out of gas at idle is going to damage a motor, what is going to happen when you run that 6 gallon tank dry at 5000 RPM?

Opinions will vary, so expect to hear the other side soon.

BTW, some of the early square pumps were junk from the factory. Maybe some still are, I don’t know because I don’t take them apart any more. The ones that I call junk had flapper tabs on the diaphragm to act as check valves. "Real" fuel pumps should have real check valves.

PS. Aslo, some of those pumps wouldn’t lift gas very high. So, if you are running a motor in a test tank, and the gas tank is on the floor, that might have something to do with it.

Well, there is some merit to all the view points I guess. I agree with Frank though, running an engine out of fuel at idle speeds will not damage the powerhead. But, like you say, the diaphragm movement surely does accelerate quite a bit just before the engine runs out of fuel, which may damage the diaphragm. I remember hearing the VROs clack up a storm when I used to run them out of fuel while fogging, I DID break a few air motor diaphragms so I stopped that practice.
I still run the small engines out of gas, and feather the choke just like you do, in an attempt to get most of the fuel out of the bowl. But, there is always a little bit of fuel left in the bowl in spite of these efforts. I always pull the carb drain plugs (if equipped) after winterization, especially if the engine will be in storage for more than just the winter months.
I don’t know if your rash of fuel pump failures is coincidental, or somehow related to the fuel you are using. If all the pumps had failed diaphragms, then I might be inclined to suspect running out of fuel might have something to do with the failures. Keep in mind that an engine that sneezes/coughs a lot is more likely to damage the fuel pump diaphragm as well. As fair as a fuel pressure gage, well you could sure set up a gage to check the engines, but you will need a gage that reads low pressures well, like a zero to five PSI gage. Keep in mind that checking just fuel pump output doesn’t mean a whole lot unless you rig up a clear hose and vacuum gage to the fuel pump inlet as well. Restriction/inlet air leaks are often misdiagnosed as fuel pump problems. So, I don’t know if checking pressure/vacuum is a realistic procedure for every engine you work on, rigging up these things can be a real pain due to stiff hoses and flimsy plastic connectors. Needless to say, doing these checks is not that big a deal if you are replacing the engine fuel lines anyway.
Many OMC fuel pump failures show up as engines that run out of fuel at lower speeds, but may run OK at higher RPMs. And, just like Frank says, sometimes we introduce problems by running the engines in test tanks with the fuel pump mounted 2-3 feet below the engine.

First, like Frank, I have been running motors dry at the ramp since my father did the same when I was a wee lad. Never had any pump problems or carb issues even after winter storage. As a teen and young adult, had two ski boats fed by 6 gallon tanks. Ran them til the tank ran dry and switched tanks. Again, no problems with pumps. I just wonder if the newer kits use a cheaper construction that fails easier. (Planned obsolescense?)

I wonder how long the fuel pump will last, whether used or not. The diaphragms were made of flexible material 50-60 years ago, in some cases. This material was not alcohol resistant. I reseal my floats, and use alcohol resistant gaskets, factory/or my own production.
Like the check valve below the carb on pressure systems, the diaphragm material may be the next to go. My most common trouble is on the check valves next to the primer bulb. The new parts seem to give the most trouble.