NEVER run your motor when in the all up position. (Sorry Divecoz)
The angle is too steep and you run a serious risk (if not the certainty) of destroying your motor due to lack of internal lubrication.
I think your Manual, Joe, clearly says you should NOT.
Every marine motor is designed to work at angles and not just in a horizontal position due to the nature of the working environment. However, there are limits. These angle limits can be different from one motor to another.
I remember my concern in the first days of our MacM wondering if in the case of motor sailing with just the main up and with an excessive amount of heel, if the outboard would not dry up of lubricating oil. After researching, it turned out that the ‘carter’ of the outboard is suitably designed, with a shape resembling an inverted cone with the end of the oil pump intake all the way at the bottom (narrow end) thus allowing for large angles of heel during operation. The pitching and rolling angles should be specified in one of the factory manuals (not the ones we get as users). I could not get my hands on one. Let me know if you do, Joe – it would be interesting to read the angle values.
Coming back to your DF70 (it is a D’F’ right ?) your only ‘flush’ choice whilst in the water is to turn OFF the engine, raise all the way up and flush with a hose connected to the side access/connecting point that is there specifically for this purpose, as the Manual clearly describes.
You want the engine all the way up because otherwise the bottom unit would remain in the water and you would not be flushing the impeller in the process which is very important as well.
The only drawback I see with flushing this way is that when you are done, a certain amount of water remains inside the engine head and cooling passages. If you were flushing this way on land, you could just lower the engine again after finishing and actually see the remaining water drain out.
If you are storing long term it is better to have a dry motor than a motor with water trapped in it even if clean water.
However, if the boat is in the water anyway, it probably means that you will be using the motor again sooner or later. So, this should not be a problem. I would just insist on flushing a little longer with this method and getting all the salt out (assuming you are in sea water) so that what stays in the motor at the end of the flushing process is clean water with no concentration of salt.
Taking this a little further; A practical way to determine how much pitch your motor can take without running dry of lubrication is to note the tilt angle when you tilt up with the boat in the water and the engine running - You know very well that there comes a point when the lower unit is not low enough in the water to suck in water for cooling of the engine. That is when the water stops coming out of the bleed hole. As a rule of thumb, I would not operate the engine beyond this angle even if do provide for external cooling.
Hope this helps.
Octaman
