Ran my outboard OUT of the water on accident...

[bulboushead]

Just as it seems, I made a big fat dumb mistake. After a successful sail, my wife and I were putting the boat back on the trailer. The engine was idling as it ran out of what gas was left in the carb. I was making sure everything with the trailer was good, and my wife said the boat was good to go also. I pulled the boat out of the water and stopped at the top of the ramp, and my wife came and got in the boat. I asked if I forgot anything, she said no, and then added "Oh yeah, the motor is still running". SHOOT!

I jumped out of the car and turned it off. It was probably idling for about 30 seconds on the back of the boat. My wife said it was still shooting a stream of water when she got back into the car, but I can't remember if it was when I turned it off. I was really upset at myself at being stupid and forgetting, and I definitely learned my lesson.

Anywho, it's a 6hp Tohatsu (bought earlier this year, maybe 5 hours on it) and I'm wondering how badly this will hurt it... I get the feeling I should replace the impeller, but I've heard that's a bit of a task...

 

[wonkodsane]

I'd be pretty surprised if 30 seconds dry did any damage to that little Tohatsu.

 

[RECESS]

I bet you are fine. I would get it back in the water and see if I had a good stream, and then be happy.

 

[Ray Bowles]

Shouldn't be a problem.

The main area of damage would be to the water pump to start with. An unloaded engine wouldn't overheat in that time frame. Depending on the composition of the material used for the water pump it might dry out first and suffer damage by running dry. The engine itself could run dry for at least 3 or more minutes before overheating and then a little more before real damage to piston/cyclinder assy.
I'd start the engine next time out and see if you have output of the water streams normal to your engine. ie. Water discharge from the back of the motor. If so then cruise on. If not after 15 to 20 seconds then I'd check the water pump impellers if your motor has changable impellers.
Ray

 

[1977oday22]

I'm pretty sure you will be fine. I had a Tohatsu some years ago.
It stood well to lots of abuse.....and always kept running.....

 

[BobM]

It's usually no big deal to change an impeller. If you have any doubts, do so, especially if you are risking your warranty by not doing so.

 

[sailaway78]

Change the impeller

Change the impeller. PERIOD Running dry for 30 seconds can do some damage. May not have but is not worth risking it on a new engine. If at some time later a warranty question comes up and there is even a hint of visible damage from running dry warranty will go out the window. It's pretty easy to do, and not overly expensive.

 

[RichH]

The main area of damage would be to the water pump to start with. An unloaded engine wouldn't overheat in that time frame. Depending on the composition of the material used for the water pump it might dry out first and suffer damage by running dry. The engine itself could run dry for at least 3 or more minutes before overheating and then a little more before real damage to piston/cyclinder assy.
I'd start the engine next time out and see if you have output of the water streams normal to your engine. ie. Water discharge from the back of the motor. If so then cruise on. If not after 15 to 20 seconds then I'd check the water pump impellers if your motor has changable impellers.
Ray

Ray's post is probably the most correct. At idle there is little heat being transferred, the pump 'was' previously wetted and therefore the impeller is/was 'lubricated', etc. 30 seconds of dry-running is NOTHING, nothing to worry about. Tohatsu OBs are VERY 'robust' and can take it.

 

[Bob Poff]

It's cheap insurance to change the impellor.

When I first started sailing I made a similar mistake. Figured it would be all right.

First trip out with my then new girlfriend, the motor overheated and left us stuck in the middle of the Susquehanna river. While head down over the transom trying to get it started, I yanked on the pull rope. Didn't know she was right behind me and hit her right in the mouth.

Once I got the motor to the shop it was a nasty bill. Not only the impellor, but a new pump housing.

Oh yes, before you ask.... fifteen years later we're married.

 

[kenn]

OK my turn

Given the short 'dry' time and the newness of the engine, I don't think there's a strong enough reason to open a new engine (potentially a warranty-voiding operation in itself) to change the impellor.

Buy a spare impellor and gasket, but test the engine as-is, (in water!) and if the water piddle is strong, you're probably OK. Make a habit of checking for the water every time you start the engine, and periodically while running, and before shutting off.

Check your manual, and solemnly promise to change the impeller when the schedule calls for it.

 

[jibes138]

Run it in the driveway

If you have it at home mount it on a sawhorse and put a trash bucket under the shaft and fill it with water. The engine cooling water will squirt outside the bucket so keep a hose running to keep it full. I do this all the time to tune up my engines. You could leave it on the transom also if you can fit a bucket under it enough to get the pump inlet under water. This way you can test it before you ruin a day by getting to the ramp and finding you have a problem.

 

[Douglast]

Re: Run it in the driveway

if you were starting it dry for thirty seconds it would be a differant story...i think your ok because there should have been ample residual water that kept your impeller lubed during the short time..

 

[bulboushead]

Thanks everyone for the tips and peace of mind. I think I will keep a VERY watchful eye on it and replace it at the end of the season if there are no problems. I live in an apartment and don't have much room to tear the engine apart on my own. Thanks for the advice!

 

[kenn]

BTW, it is never a good idea to haul the boat out with the engine running