Basic Mercruiser power steering question

[mjw930]

I feel really stupid asking this but I haven't had a boat with the stock cable steering in it for well over a decade so I'm trying to recall how the power assisted cable system works. ('96 era Bravo 1).

Everything I've had has full hydraulic steering in it so I never had to deal with a cable and the Merc valving issue.

Obviously there is a ton of slop in the system compared to full hydraulic but looking at the rear where the cable enters the power steering housing, as I turn the wheel (motor off) I see the cable housing move in and out about 1/2" in each direction in response to turning the wheel. Is this action used to direct power steering to the proper side of the assist ram or is it something broken in the housing?

I guess what I'm asking is how the system knows which side to direct fluid into the ram or even more basic, how does it work. I can't find anything on the web and this is bugging me.

[mjw930]

Oh, and it's probably a moot point anyway since I'm pretty sure I'll be installing this system within a few months.....

http://www.everettperformance.com/products.asp?category=Zeiger%20Marine&subcategory=Steering%20Products&id=28

http://www.everettperformance.com/images/productpics/helm-ani.gif

[MOP]

The motion in the cable is what move the shuttle valve to direct the oil flow.

Phil

[mjw930]

The motion in the cable is what move the shuttle valve to direct the oil flow.

Phil

That's what I thought, thanks.

[mjw930]

Why do the internal? Yes, it eliminates some of the slop caused by the cable and the brazil valve, but it doesn't remove the drive/gimbal slop.... IMO your better off keeping the brazil/cable and going to en external dual ram half system...

I disagree, there is little, if any slop in the gimbal/tiller (unless your gimbal/tiller is in need of new parts). OTOH, there is quite a bit of slop in the cable and the external half system still leaves the valve slop as it still has the move in and out to direct the hydraulic fluid.

Here's something you can try, drop the drive down so it's captured by the lower tabs on the gimbal then have someone shake it back and forth while you look inside at the tiller arm. You'll see that the drive to gimbal mounting isn't whats moving, it's the tiller arm to cable/power steering valve parts that move (and hence the slop).

According to Paul Everett, the owner of Zeiger Marine, the internal system eliminates virtually the same amount of slop as the external system. While it's true that with the partial system the drive only moves when there is input from the helm there is still roughly 1/2" movement in the valve body before fluid is diverted into the ram to make it move. When "driving" the boat at high speeds having that much motion before anything happens makes it a lot more work than it needs to be.

The only real advantage to the external system over this is the additional support it adds to the gimble which is the known weak link on the Bravo under high load conditions. My boat, in it's current configuration, is a low 60's boat and it will stay that way for at least the next season. In this configuration it will not be putting enough stress on the gimbal and tiller to be a concern and that's straight from Paul's mouth.

If I decide to do the motor and get it up to a mid 70's ride I'll consider adding the external ram. Everything I'll have in place will retrofit except for the internal ram, I already talked to Paul and confirmed that.

In addition, it means I don't have to have the external rams hanging off the transom or deal with the installation hassle of reinforcing the transom while the motor is still in the boat. When the motor gets pulled to be built or replaced I'll do the work to add the external cylinder IF I decide I need that.

Sorry for the novel but I expected this response. This internal system is new and was designed for this exact implementation, someone with a sub 70 mph boat that wants the precision a full hydraulic system brings with a stealth installation and a reasonable price. The problem Everett is having is the preconceived notions that external is the only way to go, it isn't on boats such as ours!

[The Hedgehog]

Edited for content.

Madpoodle has received 3 negative rep points from himself...

I thought it was funny.

How much it this system?

I stuck a brazil valve external assist system on my X-18. I now have zero wag when you shake my drive. I will probably go full to the helm and will only be out my brazil valve which I can sell. It was an easy install with the engine in the boat and it came with transom back plates. I paid a little over a grand. It made a huge difference in handling.

[ky-donzi]

I thought it was funny.

How much it this system?

I stuck a brazil valve external assist system on my X-18. I now have zero wag when you shake my drive. I will probably go full to the helm and will only be out my brazil valve which I can sell. It was an easy install with the engine in the boat and it came with transom back plates. I paid a little over a grand. It made a huge difference in handling.

Brazil valve external assist system
This is the system I plan to use. It is cheap, and can be upgraded to full hydraulic very easily. It seem to be safer than the internal, and if your spending the money might as well go with a system that allows upgrades. My question is how much better is full hydraulic.

[mjw930]

I thought it was funny.

How much it this system?

I stuck a brazil valve external assist system on my X-18. I now have zero wag when you shake my drive. I will probably go full to the helm and will only be out my brazil valve which I can sell. It was an easy install with the engine in the boat and it came with transom back plates. I paid a little over a grand. It made a huge difference in handling.

I have no idea what Poodle posted and I'm betting It was directed at me. I have pretty thick skin so he really didn't need to edit it but oh well.

I also didn't mean to be so blunt but I get paid to question the status quo so what I'm really doing is a "point, counterpoint" sort of thing. If you disagree with my assesment then TELL ME, I won't take it personal (unless you make it personal).

Anyway, I think it comes down to what you want to get from the system. I'm looking to eliminate the slow speed wander and provide positive feedback at speed.

I'm at a bit of a disadvantage since I've always run full systems and never taken the time to analyze the existing gimble/tiller arrangement. Everett tells me there's very little slop in the bravo gimbal so I'm taking his word on that. When I get my boat back from the trailer manufacturer I'll lock the tiller arm in place with a 2x4 and see exactly how much play is left in the system. If it's significant then I'll be the first to eat my words (I'm not afraid to admit when I'm wrong).

[mjw930]

MSRP Pricing for Zeiger systems:

1 ram Bravo add on = $1795
1 ram Bravo full = $2850
Internal Bravo full = $1995

I don't have upgrade pricing but it's probably cheaper to upgrade the add on system than the internal one since the external ram and it's associated hardware is more then the Charlyn helm and hoses.

[The Hedgehog]

I have no idea what Poodle posted and I'm betting It was directed at me. I have pretty thick skin so he really didn't need to edit it but oh well.

I also didn't mean to be so blunt but I get paid to question the status quo so what I'm really doing is a "point, counterpoint" sort of thing. If you disagree with my assesment then TELL ME, I won't take it personal (unless you make it personal).

Anyway, I think it comes down to what you want to get from the system. I'm looking to eliminate the slow speed wander and provide positive feedback at speed.

I'm at a bit of a disadvantage since I've always run full systems and never taken the time to analyze the existing gimble/tiller arrangement. Everett tells me there's very little slop in the bravo gimbal so I'm taking his word on that. When I get my boat back from the trailer manufacturer I'll lock the tiller arm in place with a 2x4 and see exactly how much play is left in the system. If it's significant then I'll be the first to eat my words (I'm not afraid to admit when I'm wrong).

I would like to know how it works out.

I put on the external assist as a band aid system knowing it was not the complete answer as well. I knew I would go to full on my 18 one day and it would cost a little more to do it in stages. I kind of did it as an experiment. It was worth it. I know I will be even happier with full but the boat works just fine for now. Much better than sotck.

[The Hedgehog]

Brazil valve external assist system
This is the system I plan to use. It is cheap, and can be upgraded to full hydraulic very easily. It seem to be safer than the internal, and if your spending the money might as well go with a system that allows upgrades. My question is how much better is full hydraulic.

I use the Mayfair system like that on my X-18. It took out most of that chine walk. It also feels much more responsive and effortless. To go full will cost about a grand more. The external assist will eliminate all drive slop. You will have to go to full to eliminate the play in the helm.

[BUIZILLA]

is overkill REALLY necessary??

[mjw930]

is overkill REALLY necessary??

Whenever possible :eek::wink:

[BUIZILLA]

YOU of all people know the answer to that question ;) ;) that's why I asked... :shark: :cool:

[mjw930]

Poodle,

No problem and you're right, it's WHEN not IF I add more power :D

I don't know what I'm going to do and probably won't until I decide to pull the trigger.

Hell, I was going to get a basic, generic trailer and now I'm getting a welded aluminum with electric over hydraulic brakes, mag wheels and all the bells and whistles. I imagine the same will hold true when it comes time to order up the steering. :shocking:

[HallJ]

I would have to say,
A full external hydraulic system would have to take quite a bit of load of the gimble as well.


Jeff