Mechanical Steering Failure
#21
Registered
iTrader: (1)
It seems Drew Marine had hydraulic cylinders that were independent of the steering and were there simply to arrest any quick turns on the outdrive. They were basically like shock absorbers to slow down the side to side motion. It was connected between the transom and the outdrive. It can be used on either mechanical or hydraulic systems. Makes sense to me.
has anybody tried them??
#22
Registered
I know a guy that used to run the Rinker/Sunsation dealership at LOTO that Pro-Charged a 24' Rinker Flotilla to run in the Shootout. I believe he had this boat running well into the 90's. One day he broke the gimbal ring running at speed and he and his passengers went on one wild ride with the drive flopping off the back of the transom. This happened with a peg-leg (single ram) partial hydraulic system. If you like running your boat like a jet ski as your avatar suggests (by the way, these boats aren't jet skis), you would be well advised to go with a dual-ram system to keep that drive in place.
#24
Registered
#26
Registered
Thread Starter
Join Date: Sep 2007
Location: HUDSON RIVER and L.I. SOUND
Posts: 434
Likes: 0
Received 0 Likes
on
0 Posts
I know a guy that used to run the Rinker/Sunsation dealership at LOTO that Pro-Charged a 24' Rinker Flotilla to run in the Shootout. I believe he had this boat running well into the 90's. One day he broke the gimbal ring running at speed and he and his passengers went on one wild ride with the drive flopping off the back of the transom. This happened with a peg-leg (single ram) partial hydraulic system. If you like running your boat like a jet ski as your avatar suggests (by the way, these boats aren't jet skis), you would be well advised to go with a dual-ram system to keep that drive in place.
Last edited by live wire; 01-21-2008 at 05:05 PM.
#27
Platinum Member
Charter Member
Join Date: Jan 2001
Location: so. WI
Posts: 1,562
Likes: 0
Received 0 Likes
on
0 Posts
It's simple enough- if you have a twin-engine installation with only one pump and you fail that engine or pump at WOT, you can expect a wild ride.
#28
'05 Concept SF23
VIP Member
I've experienced a steering failure at full throttle in a twin-engine performance boat without external steering, and I can tell you it's not a pleasant experience. Mine was due to an intake valve retainer breaking and dropping a valve on the engine that hosted the power steering pump; the engine instanteneously locked up and turned the boat 180 degrees on its rubrail (we were traveling appx 72mph). My hand got caught in one of the spokes of the steering wheel as it spun and two bones were snapped in the back of my hand and the wifey was nearly thrown out of her bolster. The incident only strengthened my love of McCleod bolsters and Formula Powerboats- a lesser V or lower quality seating may have been disastrous. We were otherwise uninjured and returned to the marina on one engine, where we cleaned out our underwear. The other boats we were with swore we had gone over when this occurred- they said all they saw was a 'wall of spray'.
My take on external steering-
1) A full external steering setup, helm to drive(s) with dual-rams is a necessity in a high-performance power boat
2) Hydrodynamic force on a propeller that comes instantaneously to a dead stop from engine or power steering pump failure is enormous, and its VERY possible that the drag on that prop could displace the fluid on any hydraulic ram causing a hard-over condition, even with external hydraulic steering.
3) Unless you have a power steering pumps one each engine (highly unlikely), and your steering system is equipped with a priority-valve system that can automatically transfer pressure to the good engine in case of engine or pump failure, it is possible to have an incident even with a full external hydraulic steering setup.
Mercruiser used to offer a priority valve kit for twin engine installations whereas an owner could have a pump on each engine for just such occcasions. To the best of my knowledge, this kit was discontinued nearly a decade ago. I've since farted around with the idea of designing something similar- I have a pretty extensive hydraulic background from my work on jet aircraft. Such valves are used quite a bit (both priority and sequencing) in aircraft hydraulic systems, especially in landing gear.
If there was any interest, I might pursue it further- it would not be too difficult to produce. As in Mercs design, one engine would be master, one slave, and upon the event of engine or pump failure, the valve would simply shift when it sensed loss of pressure on one side of its piston and transfer pressure to the steering system from the bad engine/pump to the good engine/pump. You would only feel a 'bump' in the wheel rather than a hard over, which would give you a much better chance at reacting to your failure i.e. chopping the throttles and keeping the boat on an even keel.
I'm sure the offshore racing guys and riggers have a much better knowledge of all of this than myself- I'm only speaking from my personal experience. I DO know that you should never skimp on steering, and if I ever get into another twin, I'm going to figure some way of running a pump on each engine.
Jim
My take on external steering-
1) A full external steering setup, helm to drive(s) with dual-rams is a necessity in a high-performance power boat
2) Hydrodynamic force on a propeller that comes instantaneously to a dead stop from engine or power steering pump failure is enormous, and its VERY possible that the drag on that prop could displace the fluid on any hydraulic ram causing a hard-over condition, even with external hydraulic steering.
3) Unless you have a power steering pumps one each engine (highly unlikely), and your steering system is equipped with a priority-valve system that can automatically transfer pressure to the good engine in case of engine or pump failure, it is possible to have an incident even with a full external hydraulic steering setup.
Mercruiser used to offer a priority valve kit for twin engine installations whereas an owner could have a pump on each engine for just such occcasions. To the best of my knowledge, this kit was discontinued nearly a decade ago. I've since farted around with the idea of designing something similar- I have a pretty extensive hydraulic background from my work on jet aircraft. Such valves are used quite a bit (both priority and sequencing) in aircraft hydraulic systems, especially in landing gear.
If there was any interest, I might pursue it further- it would not be too difficult to produce. As in Mercs design, one engine would be master, one slave, and upon the event of engine or pump failure, the valve would simply shift when it sensed loss of pressure on one side of its piston and transfer pressure to the steering system from the bad engine/pump to the good engine/pump. You would only feel a 'bump' in the wheel rather than a hard over, which would give you a much better chance at reacting to your failure i.e. chopping the throttles and keeping the boat on an even keel.
I'm sure the offshore racing guys and riggers have a much better knowledge of all of this than myself- I'm only speaking from my personal experience. I DO know that you should never skimp on steering, and if I ever get into another twin, I'm going to figure some way of running a pump on each engine.
Jim
#29
Registered
Join Date: Nov 2000
Location: austin,tx,usa
Posts: 349
Likes: 0
Received 0 Likes
on
0 Posts
MobileMercMan
MobileMercMan:
Are you referring to the Drew Machine snubbers, or to someone else's post/or product. It was unclear.
What was wrong with the idea? How were they mouneted? Any more specifics?
I live in Austin, in Westlake, let's get together and talk boats over a beer. I will buy.
Jim Vonwolske
512 577 7374
Are you referring to the Drew Machine snubbers, or to someone else's post/or product. It was unclear.
What was wrong with the idea? How were they mouneted? Any more specifics?
I live in Austin, in Westlake, let's get together and talk boats over a beer. I will buy.
Jim Vonwolske
512 577 7374
#30
Registered
That must have been some Rinker to be running in the 90's with a procharger.My buddy had a 24' a Searay with a Blower shop 850hp dyno'ed motor and he was only getting about low- mid 80's he got rid of the hull because it was a death trap.I used to race those jetski's back in the day so I know what they look like but thanks for the tip.The Avatar shot was taken while passing my old mans boat.