Your right, when it comes to ether, everyone seems to have an opinion. That said, a diesel engine doesn"t give a crap whether it"s running on diesel fuel, or ether, as long as the amount metered into it is "right". By that I mean over fueling an engine with either diesel or ether will ultimately cause damage in some form. The thing with ether is that it creates extremely high pressures in the combustion chamber if you spray too much in, and the ignition often happens "out of time" due to the lower ignition temp causing it to all explode before the piston reaches the correct point in it"s stroke.
The mistake most people make is trying to FOG it into the engine, in large amounts, thinking it will help start it faster. This usually turns into the engine making a really loud clunking sounds as the excess ether EXPLODES "out of time". Too many starts like this and you wind up with broken piston rings, the possibly of a bent pushrod or valves, etc, etc. Properly used the engine doesn"t know whether it's burning diesel fuel, ether, or gasoline(a rag wetted with gas laid on the air filter is another way to get one started on a cold day). Too, with the use of a starting aid, the engine starts faster so spends less time turning over with little to no oil pressure, thereby reducing wear on the internals, not to mention creating way less of a load on both the starter and battery, thereby prolonging the life of both of those parts also.
Many times I have gotten an engine running by misting a little bit of ether into the intake air stream as it was turning over. Then, by giving an small, intermittent shot of ether into the air stream I"ve kept them running long enough to bleed the fuel system (on ones where the injectors aren"t accessible to do it the usual way), or long enough to verify a problem when troubleshooting another fuel supply related problem.
Ultimately the ether itself won"t hurt an engine, regardless of what the doomsayers would like you to believe. What hurts the engine is the person doing the application being too heavy handed with the amount used. In fact most mfgs have ether start systems available for use on their engines when they are operated in cold conditions. I know for a fact that Detroit has an electronically controlled setup for the Series 50 engine in my service truck as I looked into it some years back. I wound up going with a manual setup from Quick Start since it was about a tenth the cost of Detroit"s electronic one, and works just as good. The main thing is that the charge of ether is metered through an orifice so you only get a really small shot for each push of the button.
In the end, yes, used improperly (ie-in excess), ether will kill and engine quicker than just about else you can do. As far as getting one addicted to ether, that usually happens because the engine has been fogged too many times, compression rings get broken, or worn due the ether washing the cylinder walls and basically causing scratches. Basically it creats conditions that lower cylinder pressures to the point that ether has to be used to get the engine running.
Ultimately, used PROPERLY, ether is an engines best friend when it comes to getting it started in cold weather, especially when it gets a little worn (naturally) and compression isn"t quite where it should be, and even more so at lower temps and glow plugs, a block heater, etc aren't available.
KBi
Quick Start