Need Engine Tilt Advice

[acmaui]

We took Spindrifter (2008 M) out for some shake down cruises in the South Sound all day Saturday and Sunday and after a few blunders here and there (hit the electrical panel on the dock when we came in to our slip) everything is working well and we're starting to look like a crew. Here's the situation, when I had the boat on the trailer and had the motor (70 hp Suzuki) tilted all the way down to where it stops against the transom mount it just looked to me like it was tilted to much compared to the paint lines and the bottom of the hull. It wasn't on level ground so I couldn't be sure, I was just eye-balling it. I took a level and placed on the fins that run parallel to the prop shaft and then tilted the motor so that it was perfectly level and then I moved the level to the top of the engine cover and found a place where it was level to the shaft and fins and marked that place so that I could check the level when the boat was in the water and the engine was down. Results: In the water the motor tilts down so far that the prop shaft is pointing towards the sea floor as opposed to parallel to it, maybe only 10 to fifteen degrees at the most when the boat is stopped, but obviously that would get worse as you come on plane. I tilted it to level (using the level) while operating at about 4000 rpm and the rpms didn't noticeably drop and there was at best subjective improvement in sound or feel, although since it was off the transom clamp stops it was quieter since the hull was not getting the vibrations of the motor through that contact. I worried though that operating in this manner would put to much strain on the tilting/leveling system since the piston assembly would now be taking up all the strain of the thrust that was on the transom clamp assembly stops previously. Here's the question, is this normal for a 2008 Blue Water Yacht M with the Suzuki 70? I ask because to me it looks like the white tapered shim pad that goes between the transom and the outboard clamp assembly would explain the resulting prop angle. I'm wondering if the factory puts this shim on for the motors they sell (not Suzuki) and that Blue Water Yacht is not taking this into consideration when they mount the 70's. Any idea on this? Am I over thinking this?

[Ormonddude]

The Shim is normal and with the engine all the way down it should slightly beyond 90 degrees on most installations and yes the hydraulics are designed to handle the engine thrust at trim so it sounds like your OK - I ran my engine aground at JMGT 2012 and the pump locked up so I will be watching the tilt/trim threads lol first I am going to manually tilt it using the release screw then I am going to check the Motor and walk my way around the system first checking the electronics then working into the hydraulics (most likely get a seal and O ring kit) and get it sorted out

[K9Kampers]

acmaui-

Sounds like you are refering to the "trim" range of the OB, which is different from "tilt". Larger units usually have separate switches for the two functions. What you've described sounds typical for triim characteristics. When the OB's propshaft is level with the water, trimming up (prop moves away from hull) lifts the bow, helping to plane. Once on plane, trimming down (prop moves towards hull) brings the bow down to help counter porpoising.
Relative to when the propshaft is level with the water, there will be 'positive' & 'negative' tilt ranges. It is not normal to expect the motor to ride on the tilt bracket stops all the time. The trim / tilt mechanism is designed to handle the load.

[NiceAft]

acmaui,

This may be of interest to you. It basically reinforces what K9Kampers has said.

http://www.ehow.com/facts_7295495_prop- ... boat_.html


Ray

[raycarlson]

with just 50-70 hp to use on a 5000# 26M your trim will have little or no effect, to find out how trim works borrow a 20 foot bass boat with 200 hp on back, then you will see what trim can do, for your M just leave it on the stop.

[Don T]

Hello,
I find keeping the motor trimmed properly improves fuel economy / speed for any given throttle setting. I have been using the power trim on my Tohatsu since 1995 and the only issue I had was the need to replace the tilt bushings (plastic) after 15 years.

[Russ]

We have the same boat, same year, same motor, same dealer.
I think BWY started using those white shims to improve performance. The Mac doesn't really get up on plane totally, but the extra tilt helps. Others have installed the shims to help with the angle to improve getting the stern up higher.
Yes, it does make more sound tilted all the way down because of what you described. The motor it now transmitting more vibration through the transom.

The Suzi 70 has a tilt/trim motor. You will notice it tilts fast until it reaches the bottom of the range and then it slows way down for trim. It is designed to be trimmed in the last few degrees of the movement. It won't hurt the pistons if it's not fully down. It is designed to be run this way.

What I found (too late) is the Suzuki has a top tilt limit adjustment so it will stop before hitting the seat. Overall, it's been a fantastic motor. Not a lick of trouble, easy to change fluids and flush with a garden hose via the port in the side.

Relax and enjoy your BWY Mac. I'm learning that they do some nice mods that I assumed were factory but are custom from the dealer.

[acmaui]

Thanks to all of you! I now understand the trim basics and will play with it a little more. Now if I can just figure out why my transducer data suddenly stopped making it to the Garmin I'll be a happy boater again. We were on our way back to port motoring around 400 rpm and suddenly no water temp, no water speed, and no depth reading. The transducer is still there and looks fine, I first expected that it may have been ripped away by one of the many Puget Sound logs, but it's still there.

[Russ]

Thanks to all of you! I now understand the trim basics and will play with it a little more. Now if I can just figure out why my transducer data suddenly stopped making it to the Garmin I'll be a happy boater again. We were on our way back to port motoring around 400 rpm and suddenly no water temp, no water speed, and no depth reading. The transducer is still there and looks fine, I first expected that it may have been ripped away by one of the many Puget Sound logs, but it's still there.

I assume the GPS is still working.

Check your battery level. I had similar thing and found the house battery was very low. No depth or temp. The combiner wasn't working correctly and it never charged that one. Maybe you had the same tech wiring your boat.

[Catigale]

We were on our way back to port motoring around 400 rpm and suddenly no water temp, no water speed, and no depth reading.

...was there a sudden crunching noise and did the water suddenly look brown?

[Ormonddude]

400 RPM? Idle is 800 RPM how did you manage that? you must mean 1400 RPM on Many depth units there is a low battery shut off setting in the set up programming Make sure its set for 12 volts I had the same issue recently I would turn it on and it would power up and then Shut off it was set to shut off anything under 14volts? so you may want to check that.

[acmaui]

400 RPM? Idle is 800 RPM how did you manage that? you must mean 1400 RPM on Many depth units there is a low battery shut off setting in the set up programming Make sure its set for 12 volts I had the same issue recently I would turn it on and it would power up and then Shut off it was set to shut off anything under 14volts? so you may want to check that.

Yeah, I left out a zero, should have been 4000 rpm, which made the post loose some context in that we were flying along fairly fast and I thought that maybe at that speed I hit something small that could have damaged the transducer. Anyway, I went down to the boat in full investigate mode with all my meters and tools and when I plugged the Garmin in and fired up the circuit that feed it everything was back to working fine. So, I'll keep an eye out for any inconsistent operation in the future and hope it was a transient fault.

[Russ]

Glad it's working. But I would still check voltage. Like I said, mine started acting wonky (no depth, speed) when the voltage dropped). Everything else seemed fine. Turned out to be no charging on my house batt.

BTW, do you plug in when at port? Maybe THAT charges your batts back up and makes everything happy again.

I don't have shore power and it took several weeks (of first season with the boat) to notice the house batt wasn't charging.

[acmaui]

Glad it's working. But I would still check voltage. Like I said, mine started acting wonky (no depth, speed) when the voltage dropped). Everything else seemed fine. Turned out to be no charging on my house batt.

BTW, do you plug in when at port? Maybe THAT charges your batts back up and makes everything happy again.

I don't have shore power and it took several weeks (of first season with the boat) to notice the house batt wasn't charging.

Yeah I plug it in at the slip as soon as we get back. I'll check the batteries state of charge when we get back next time. Hope it's good since if it isn't that could mean even more expensive solutions.

[Russ]

Interesting. Perhaps plugging in fixes the low batt problem because it powers the charger.dd

You have a 2008 BWY boat and so do I. My battery combiner was wired backwards.
The combiner is supposed to charge the house batt when the engine is charging the starting battery. It wasn't. It only charged the reverse. It charged the starting batt from the charger when plugged in. When the engine was running, it never charged the house batts.

Very easy fix.

The GPS (and other house appliances) are wired to the house batt. The starting batt is dedicated to the motor. So when the house batt on my boat ran down the GPS lost depth and temp. Everything else seemed okay.

I would bring a voltage meter with you and if it acts up again, check it.
Oh.....if you have the same GPS (Garmin 440s) then press Select, down to Sonar, select and it will display the battery voltage at the bottom of the screen. Easy to test if voltage is the issue if it acts up again on you.

--Russ