Here in NC we are under a HUGE freeze and I am still working on tuning the boat in the garage.  The Johnson 70 is a 2 stroke and coming along well.  Question is the earmuffs are pretty much un-usable now because of the freeze.  Can i crank it just for like 5-10 seconds without any kind of water flow?  A guy told me it takes about 30 seconds to get into issues that way.  Also, does the water serve as a cooling agent only?  Or does it help to lubricate anything on the boat?

Wouldn't recommend it, although you would probably be ok for a real short time, as long as you weren't doing it repeatedly in a short time working on it.  The most common issue with running it without water would be overheating your water pump impeller which can cause it to break apart.  Best case scenario, you realize it happens and just replace the impeller.  Worst case scenario, it breaks up and little pieces block off your water passages, causing one or more of the cylinders to not be properly cooled and overheat when it's ran again.

 

One of those things where you would "probably" be fine, but is it really worth the potential expense if something goes wrong?

Good call. I'm going to wheel the hose reel in the garage and that way it is not iced and can run water through it if need be. The guy was a boat mechanic and said it would be the water pump. He said he's seen cog fleas boats come in from people who cranked their boat to show off at the gas station and now had the 2 hour job to him. :-/

Yep you can fry a water pump in a heartbeat. Totally not recommended to start one dry.

I freak out when I'm in shallow water and forget I have the motor trimmed up and then try to start it when I reach deeper water.  I just know that I am frying the impeller.  Same thing when I am launching the boat and forget to trim it down.  Old men forget things, and the things we forget can hit us dead square in the wallet.

You may be able to get the lower unit into a clean trash can / barrel  then fill with water.

Now that's a good idea too!

We used the barrel method when we had the Bullet. The big blue drums cut in half work perfectly, unless you plan on really giving it a few revs.