Thread/Pitch on steering hydraulics on 2800? - Maxum Boat Owners Club

codingparadox · 01-02-2018, 12:51 AM

I'm investigating which kit I can pick up with premade hoses/Ts for installing an autopilot system on our 2800 with Bravo 3. Anyone have any idea what the threads on the connections at the outdrive are? I need to basically pull those off, T them into the autopilot pump, and then reattach hoses off the T back to the outdrive. I'd rather not pull those off until I'm ready to attach and bleed, for obvious reasons, so I'm hoping someone has already done this to save me one round of bleeding.

mmwjr · 01-02-2018, 02:44 AM

I’m not sure what the thread size on the steering assist cylinder but I believe at some point Mercruiser switched to quick disconnects but don’t recall the year.

BTY is the system you are looking designed for a steering assist I/O and not hydraulic steering? The two are greatly different.

codingparadox · 01-02-2018, 07:55 AM

I'm looking at adding the Garmin Reactor 40 Compact system. It says it's fine to install with power assist, you just do it between the assist and the steering cylinder, which is the convenient place to put it anyway.

So I'm looking to figure out what the threads are at the cylinder so I can disconnect there, T the lines, mount the pump right next to it, and go from there right back into the cylinder.

http://static.garmin.com/pumac/React...tall_EN-US.pdf

mmwjr · 01-02-2018, 12:30 PM

Does not make sense to me a the PS assist does not steer it reduces the force needed to move the steering cable. The cable still is turning the boat. This system is for true hydraulic steering where the helm is a pump that pushes fluid instead of turning a cable. I recommend you talk with a Garmin rep before proceeding. Yes I read the attachment and I don't come away with it working on an assist steering that an I/O is equipped with.

shrew · 01-02-2018, 02:19 PM

Bravo 3 should power assisted cable steering. I don't believe that is quite the same as hydraulic steering.

codingparadox · 01-02-2018, 06:53 PM

Is it really not fully hydraulic? I'll have to dig through the lines again, and check the steering module at the I/O, but it looked like hydraulic lines coming from the helm down to the assist module. Will report back. Thanks shrew.

mmwjr · 01-02-2018, 10:34 PM

Unless someone changed it the factory steering is cable with assist.

codingparadox · 01-02-2018, 10:35 PM

Yeah -- on vacation now, but I thought I saw the seastar hydraulic replacement cylinder on the I/O. Will check later this week when I'm back.

mmwjr · 01-02-2018, 10:49 PM

Quote:

Originally Posted by codingparadox

Yeah -- on vacation now, but I thought I saw the seastar hydraulic replacement cylinder on the I/O. Will check later this week when I'm back.

Yes I believe they do make a system to do this. Enjoy your vacation.

shrew · 01-03-2018, 02:28 PM

I'm hoping someone can answer, as I cannot. With power assisted cable, you can turn the wheel from side to side and move the outdrive (albeit with a good deal of resistance) even if the engine is off. Can you do the same with straight hydraulic? I assume you would need the pump working to do so.

Embarrassing, as I have hydraulic steering on my current boat, but never tried it.

mmwjr · 01-03-2018, 05:18 PM

Quote:

Originally Posted by shrew

I'm hoping someone can answer, as I cannot. With power assisted cable, you can turn the wheel from side to side and move the outdrive (albeit with a good deal of resistance) even if the engine is off. Can you do the same with straight hydraulic? I assume you would need the pump working to do so.

Embarrassing, as I have hydraulic steering on my current boat, but never tried it.

A true hydraulic system does not require any power so yes you can operating the steering without the engine being on. Based on the manual the OP provided this will still function as the Auto pump is in parallel to the helm pump.

mmwjr · 01-25-2018, 05:19 PM

Quote:

Originally Posted by codingparadox

Yeah -- on vacation now, but I thought I saw the seastar hydraulic replacement cylinder on the I/O. Will check later this week when I'm back.

Have you determined what type of steering you have?

codingparadox · 01-25-2018, 06:20 PM

I assume that it's cable-driven, but it looks like a weird system. There's one hard line coming off the starboard side heading back up to the helm. Since it's only one line I can only assume it's cable. However, right next to the cable inlet on the steering rack, there's two hard-crimp fluid lines that scream high-pressure hydraulic fluid, but then they T into two very large soft lines on the back of the motor, and I don't know what runs through that.

So, in any event, looks like it's cable steering (though I'm still curious what those lines are -- part of the power assist somehow?..)

I've talked to the Octopus drive guys and it looks like it'll be around 1000$ for the octopus drive for the cable steering, plus around 1300$ for the Garmin ECU/CCU to power/control the drive. Not too bad, but I was hoping for cheaper. That project will have to wait until the summer, I think. Dropping 10k into the boat already is leaving me a bit sore.

mmwjr · 01-25-2018, 10:26 PM

Yes that is the steering cable going to the helm. Can you tell where the metal or soft lines connect? Trim tabs? Can you post a picture?

codingparadox · 01-25-2018, 10:47 PM

I'm away on another trip through Monday, and can post a picture when I get back. The lines look like coolant lines (they're ~1 inch diameter soft lines running side to side across the back of the motor), but I haven't tried digging into anything there. It's definitely not connected to the trim tabs, that has a separate system.

mmwjr · 01-25-2018, 10:56 PM

I forgot is your 7.4 MPI with a cool fuel module? If so they may be to coolant lines to that.

codingparadox · 01-25-2018, 11:36 PM

It's a 7.4 MPI but I don't know what a cool fuel module is.

mmwjr · 01-26-2018, 02:48 AM

It’s Mercruiser’s fuel management system to reclaim the return fuel from the fuel rail that feeds the injectors to recirculate the fuel with new fuel drawn from the gas tank. On cars this would get returned to the fuel tank but not on boats of this vintage. The system required cooling so they plumbed engine coolant to it.

codingparadox · 01-31-2018, 04:26 AM

codingparadox · 01-31-2018, 04:28 AM

The hard lines heading to the right in the picture there are the ones I'm talking about. One goes into that side-to-side plastic tube connected to large soft 90 degree bends that go under to the sides of the motor and seem a lot like coolant lines. The other heads straight down and I didn't bother to see how far it went.