Drive up at Idle question?

habit68

Hi gang, I was wondering how much can you trim up the motor at idle and still get enough water into engine for cooling? If the exhaust is out of the water at full trim up and idle speed is this ok or will damage be done?

Thanks!

brianluck

High drive angles are also bad for the joints

habit68

even at Idle??

Lifes Good

even at idle.

brianluck

Generally I won't operate my drives any higher then 1/4.Up ,99% of my boating is done with drives full down now that's not saying if you get yourself into a pickle in shallow water that you can run them just below the surface to get out but extended periods at high angles is stressful causes head and wear think of a lifted truck with high drive line angles. That man will be replacing joints twice as often as a factory truck

gslpro

Habit, The answer to your question is that yes, your engines will get enough cooling.  The pickup is at the 'front' or bottom side if trimmed up.  As far as running them at max trim, you will hear your u-joints rumble a little the higher you go.  Not sure of your situation, but when I back into a sandbar, I trim close to 3/4 of the way up.  My props are still active, but the drives are not below the keel at this point.  Once I am where I need to be, I trim all the way up.  When I leave, I drop them back to 3/4 before starting the engines, and then use idle forward to assist the windlass, and then drop the trim in increments as I crawl through the depths to 4 feet plus.  The idea of  u-joint is drive the shaft at an angle.  Low power use of this will not increase degradation of the joint substantially.  Throttling up while severely trimmed most certainly will though. 

Dream_Inn

gslpro said:

Habit, The answer to your question is that yes, your engines will get enough cooling.  The pickup is at the 'front' or bottom side if trimmed up.  As far as running them at max trim, you will hear your u-joints rumble a little the higher you go.  Not sure of your situation, but when I back into a sandbar, I trim close to 3/4 of the way up.  My props are still active, but the drives are not below the keel at this point.  Once I am where I need to be, I trim all the way up.  When I leave, I drop them back to 3/4 before starting the engines, and then use idle forward to assist the windlass, and then drop the trim in increments as I crawl through the depths to 4 feet plus.  The idea of  u-joint is drive the shaft at an angle.  Low power use of this will not increase degradation of the joint substantially.  Throttling up while severely trimmed most certainly will though. 

Couldn't have said it better! >-

habit68

Thanks gang, I usually get into 2 1/2 to 3 foot sandbars to anchor for the day. I basically do what you have explained, idle in with drive about 3/4 of the way up so exhaust is just below water then shut down and trim up.

Thanks for all the input!

brianluck

On my fv300 even at full up trim my props are still under water

gslpro

Brian, I meant under water enough to be engaged with some thrust.  Once you trim all the way up, you have minimal ability to move the boat or steer.  It just sort of flounders while pumping a lot of water under your swim platform.

Michael T

Habit68, your engine will get enough cooling with your drive up as I don't believe you use the "trailer up" switch which could retard cooing .There is significantly more wear on many critical pieces of the drive components running with the drives up - if they are up a lot. Drives up a lot is for bringing a boat in and out of the water and unusual circuimstances - not as a habitual thing. You can minimize wear by not nexceeding idle and not doing it for lengthy periods. You also run the great potential of sucking a lot of sand into your engine. You should change your impellers at least once a year and probably more often. My friend owned a marina and guys who came in with unexpected heating problems often had water passageways clogged with sand from being at sandbars. Being a Canadian, you probably have heard of sandbanks in Canada - a real impeller killer destination. You have a cruiser not a flats boat. My 2 cents is to keep it in at least 5 feet of water for the sake of your equipment. MT

habit68

thanks Mt,  but I live on Lake simcoe and tying up in 3 to 4 feet of water is how summer is spend for about 80% of the boating public on one of Ontario's busiest lakes. It hasn't  seemed to hurt any of my friends cruiser for the past 10 years they have been doing it so I guess I will just be careful with idle and trim!

http://www.beechmarine.com/Boating_page_3_Simcoe_raftup.htm