Motor position while towing

B

browntdb

New member
I have read many places on the internet that suggest the motors be placed in the down position when towing the boat on its trailer. With Tortuga, I cannot do that because the motors are only about a foot off the ground when down. My album shows the position of the motors resting on their flip down supports. The hydraulic cylinders are extended in this position and I assume supporting the motors from changing position in case of a bump?

I have only towed the boat from Medford OR to Corvallis OR several months ago. We are about to begin our boating this season andI don't want to damage the motors in any way when towing by leaving them in this postion and a hard bump dislodging them. The only other boat I had allowed the motors to be placed in the down position when towed.

Should I worry about towing as shown in the photo? Any alternatives? Perhaps the tilt hydraulics prevent problems?
Thanks,

Terry
 
Hello!

Welcome to the C-Brat site!

You'll find this is a very common topic of discussion around here, and one with some differing opinions.

I suggest you go to the Outboards and Systems Forum and look though the topics. A lot of them address this question.

Good Luck!

Joe. :teeth :thup
 
I believe the issue is stress on the transom. With a 350 lb engine [my 90 hp, 4 stroke] tilted up, the engine acts as a lever arm stressing the transom back and forth. With the engine down, the stress is in an up and down direction instead. The up and down movement doesn't stress the transom like the back and forth does. If you're driving on I5 between Medford and Corvallis, I would think one foot off the highway is enough clearance. I tilt my engine up slightly to get around one foot off the road and lower the engine onto a two by four sandwiched between the shaft and engine bracket so the hydraulics are relieved of holding the slightly elevated position.
 
There have been several threads on this recently. Generally, the issue is the stress on the tilt cylinder. The transom is made to take the load (consider bucking thru 2 1/2 foot chop at 25 mph.) There is also the issue of road vibration.

I have always used some form of support. Currently I am using MY Wedge http://www.m-ywedge.com on the C Dory 22 with a Honda 90 and a "Transom Saver"--a spring loaded square tubing between the lower unit and the trailer aft cross member. I have also used 2" dowel rod and pieces of 2 x 4.

There are those who use the small tabs on the side for support. Many manuals note that these are only for working on the motor, and not for trailering. I have seen several break--and you can imagine what happens to the lower unit in that case.
 
I'm on the same page as Thataway.

1) I feel like the best position for the motor when towing is fully down, IF you can achieve that without hitting the ground. I can tow with my kicker this way, now that I have it on the Mini-Jacker -- but not the main (it would hit the ground).

2) So I have to tilt the main (Yamaha 80). The manual says in no uncertain terms not to use the tilt holder-upper-lever. That is for when working on the engine in a static (non-towing) mode. It's also not supposed to rest on the tilt cylinder alone (stresses it). So that leaves propping it up somehow.

a) Transom saver that goes to trailer. Supposedly not good because trailer flexes differently than engine and imposes stresses and movement (I have not used one).

b) M-Y Wedge. I bought one of these and thought it was really slick, but I had a failure of mine on my last trip. It deformed and worked its way out. I *think* my motor wasn't damaged. My current thought is that the instructions tell you to put it in backwards, but... I'm not sure (?). I think I had it in "backwards" from the instructions for my first 5,000 miles of towing, and it worked beautifully. Then I read the instructions and realized I had it in 180º opposite from what they show, so for my next trip I put it in right, and it deformed and failed. So... not sure what to think. It does seem like a great product.

c) Dowel or piece of wood. My motor is shaped better for a slightly modified 1" x 2" type piece of wood than a round dowel. I made one of scrap at a rest area when I found the deformed M-Y Wedge and the engine towed perfectly with it the next few thousand miles. I'm about to head out again and it will be with a similar piece of wood, only made of something better than the ply scrap I had at the rest area. I note that the parts on my motor bracket that are contacted by the "board" are pretty sturdy looking. So while the resilience of the M-Y Wedge seemed like a good idea, I don't think I need it on my particular set up (I was told that certain castings can break, but I have not looked at that many other ones).

Many others have a lot more miles under their belts than I do, but this is over around 10,000 miles of towing, so at least not just "around the block." However, that said, I only have my tow motors' worth of experience, as previously I never towed anything with an outboard left on the transom.

Sunbeam
 
My lower unit sits pretty close to the ground when the motor is down (couple of inches). The previous owner towed the boat around for 5 years using the tilt lock and never had a problem. I put a piece of 2x4 across the top of the transom part of the mount and bring the motor down till the wood is snug. This gets the lower unit well up.

If you look at the way the motor sits on the transom, even in the down position, the CG of the motor is about a foot aft of the transom and about even with the top (for the motors used on a CD-22). The dead weight of the motor and any acceleration of the motor is going to result in a torque on the transom. It will try to twist the transom backward off the boat. If the motor is tilted up, the CG will move forward and you will relieve some or all of the torque from the dead load of the motor. Vertical motions of the engine (e.g. road bump) will be a more vertical load on the transom and less of a torque.

It is possible to have a transom structure that is good at handling the aft torque of the motor (in the normal position) but not be so good at handling a forward twisting (as when the motor is tilted up). But designing it this way would be more difficult than just making a beefy structure.

The load placed on the transom during normal operation (say going to WOT from a standstill or hitting a large wave at speed) puts a vastly greater load on the transom than occurs from normal road bumps when trailering. When the engine is at speed you have hundreds of pounds of thrust on a ~2' moment arm. Being able to handle this load results in a transom that is more than able to handle the weight of the motor in pretty much any position.

Any boat where this was actually a real concern is a boat that I wouldn't want to be on.

My $.02.
 
On my past boat, an I/O, they made little plastic sleeves to fit over the cylinder to take the load off the hydraulic trim. Too bad they don't make something like that for the outboards. I trailered my CD-22 with Merc 115 Hp EFI 4-stroke quite a bit last summer. I leave it in the down position, and probably have a foot clearance between the skeg and the ground. Definitely not much more than that. I have pulled out of various driveways and if I'm not sure, I've gone pretty slow. So far I have not hit anything. I have an Ez Loader trailer and the wheels are a ways back. I'm sure the skeg has come close, but so far, no scrapes in the bottom of it. Unless you are going over some steep dips, I don't think you will have a problem if you have a foot of clearance. Colby
 
Since we live in Boise, we tow everywhere and our boat spends huge amounts of time on the trailer. The way I approached the issue was to use what Honda calls the transom angle adjusting pin. It came with one on the 75 on our 22 cruiser, and we trailered with pin in the top hole and never had a problem with dragging the skag on anything over 10 plus years, and many miles. I found it to be quite handy as one does not have to get under the boat to attach a travel support, and still got the pressure off the tilt cylinders. On the water I store it in the bottom hole and it never interferred with trim. It worked well enough that even though the 50 on the C-Squirt didn't come with the pin, I bought one and use it the same way. Another item on my check list is to tow with the directional control in gear to prevent the wind from rotating the prop.
Cheers
Jack
 
If you use a M-Y Wedge, be very careful! The rubber is hard enough to crush the metal top of your trim/tilt cylinder if you forget it's there :cry and power tilt your engine(s) down. Don't ask me how I found that out! :cry:

Charlie
 
Colby Smith--the M Y Wedge is a heavy duty item which fits between the tilt cyl and the motor, similar to what you describe.

I am using Charlie's wedge--but I am careful to remove it before using the boat. Part of prep for the water is a walk around, to check the transom drain plug, that all straps aft are off the boat, to check the prop, to check the trim tabs, transducers and motor mounts. During this walk around I remove the M Y Wedge using the motor mounted tilt/trim switch.
 
thataway":2a61iauf said:
Colby Smith--the M Y Wedge is a heavy duty item which fits between the tilt cyl and the motor, similar to what you describe.

I am using Charlie's wedge--but I am careful to remove it before using the boat. Part of prep for the water is a walk around, to check the transom drain plug, that all straps aft are off the boat, to check the prop, to check the trim tabs, transducers and motor mounts. During this walk around I remove the M Y Wedge using the motor mounted tilt/trim switch.
Click to expand...

I had two of them which crushed my T/T cylinder reservoirs on my old TC Suzi 115's. Very expensive as the motors had to be lifted off the mounts to replace them. IMHO, you should put a red ribbon on them like the aircraft folks use to remind them to take out locking pins. Although, the boat, in my case was on the trailer after a trip and I was about to flush the engines, just didn't look, red flag or none, I couldn't see it from the helm anyway. You cannot fix stupid!

Charlie
 
These work well. DO NOT TOW ON THE MOTOR LOCKS!
It says that in most manuals . They are for working on the trim and tilt units. We have replaced a number of bent and broken ones . A two by four wedged in is a simple solution but the Yamaha part or similar is fine .
Marc
 
As I mentioned earlier, I don't use anything on my outboard. It's a single Merc 115 hp, and I just leave it down. I have had no problems trailering that way, and I think I'm actually less than 12" off the ground. Perhaps only 9 or 10".
 
I tow with the engines down. If you look at the first pic in my "Launch Day" album, you will see I have about 18" clearance. Part of the underneath of my trailer is lower to the ground than my props.

Martin.
 
This is my solution to the problem:

P4220001.thumb.jpg

I made wooden braces to fit as shown. Before trailering I raise the engines to allow the braces to be inserted, using trim put just a little downward pressure on them so they are snug, and head out. They have worked well for thousands of miles of trailering.
 
colobear":3gp7jekl said:
This is my solution to the problem:

P4220001.thumb.jpg

I made wooden braces to fit as shown. Before trailering I raise the engines to allow the braces to be inserted, using trim put just a little downward pressure on them so they are snug, and head out. They have worked well for thousands of miles of trailering.
Click to expand...


This is exactly what I do to support my motor when trailering.
 
As the original poster, I thought I would pass along what four authorized Yamaha Dealers told me. The first was the lady that works at the front counter. She said that Hondas could be towed with the motors on the tilt brackets but Yamaha's could not. I called another dealer and the fellow said that Yamaha's could be towed with the tilt brackets in place.

I then called two more shops and talked to the actual mechanics who service Yamaha Outboards. One told me that the strongest part of the Yamaha assembly is the hydraulic piston that tilts the engine. As a result, he said to not lower the motor down to the tilt brackets, but to keep it tilted and let the hydraulic cylinders hold the outboard.

The last service tech I talked to agreed that the hydraulic cylinders were one of the toughest parts of the motor, but he said to go ahead and let the outboard rest in the tilted postion on the tilt brackets.

The Yamaha website FAQ says to not let the outboard rest on the tilt bracket. I don't know if that is for newer outboards. Mine are 2005 models.

Even the experts can't agree. I have decided to let the outboard rest on the tilt brackets while towing, and if they ever get bent for any reason, get them replaced.

You would think with the miles Yamaha outboards are towed every year, that there should be some real world testing and consistent recommendations from the factory and their authorized service representatives.

Terry
 
Terry,
I have a 2008 Grady White Tournament 225 with a Yamaha F-250 TXR on a Gill bracket. I tow it 300 miles round trip to Lake Cumberland constantly. I have always used one M-Y wedge on the port side and have never had any problems. I would highly recommend the M-Y.
Wedge.
 
As a partial follow up on the M-Y Wedge issue I mentioned:

First of all, when I got the wedge, I happened to be at the Yamaha shop, and the shop fellow simply popped the wedge on and trimmed the motor down. Okay, seemed fine, and I got on my way. The solid part of the wedge (180º opposite the slit) was facing aft. I trailered around 6,000 miles without a problem.

Then, a few months later, I was getting ready for another long tow, and since I had not put the wedge on the first time, I wasn't exactly sure how much "oomph" to let the downward trim have when I trapped it in place. So I went to their website and read the instructions they have posted (it's the "Universal" wedge). Lo and behold, I noticed that they said, in all caps, with many exclamation points, (quoted):"pop it on AND THEN TURN IT 180º SO THE SOLID RUBBER FACES THE BOAT!!!"

Oh geez, I thought, I trailered all that way with it in backwards :shock: That'll teach me to just let someone else do it without me checking the instructions. Luckily there was not a problem. Whew! So I made sure to put it in how they said, which makes it so the slit faces aft instead of the solid part. Around 1,000 miles later, I had a pretty bad failure of it (photos in another thread from back then). Basically, it deformed so the slit opened up into a smile, and my motor was allowed to sink down as it rode on the trim cylinder only. The only thing that stopped a complete catastrophe (engine will drag on highway if it goes all the way down) was that the wedge got wedged between the tilt shaft and my transom. I actually had a hard time getting it off the tilt shaft because it had sort of hardened itself into the deformed shape.

So I made a prop board in a rest area out of part of an IKEA bed slat, with a hacksaw blade and a plane. That worked the rest of the way (1,500 miles or so), but the board was sort of deformed and cracked when I arrived (not enough so that the motor budged, but it was obviously only a temporary solution).

But, the style had worked, and I figured I could do better than a cheap piece of interior ply made of "white wood," so I made another board just like it, but out of a good piece of hardwood. That one started to break up after around 500 miles (problem is, it only partially rests on a metal "shelf" on the motor bracket, and there is a stress riser). I was still surprised it cracked up that soon though. Still had a piece of the same bed slat, so IKEA Bed Slat 2.0 was created in a parking area alongside the highway. That lasted the next few thousand miles.

Back to the M-Y Wedge though.... there was another mystery. A while later, after all this happened, I watched the "how to" video on their website. In that, they just pop it on and DO NOT turn it 180º, then lower the motor onto it with the hard rubber part facing aft (which is opposite to the emphatic instructions but is how I had it for the first, successful 6,000 miles). I had noted that dichotomy a few months ago, but at the time just figured, "forget the wedge, I'm sticking with my simple wood board," and so didn't do anything about it.

So, at the same time I was parked and making Bed Slat 2.0 (the board method obviously wasn't the rousing success I had thought it might be), I called the fellow at M-Y Wedge and talked to him about it. I still had the wedge aboard and was thinking about re-using it in the "wrong" orientation. The fellow at M-Y Wedge (who called me back ASAP, at my request) said they had not had any other failures (which, even when true still bugs me slightly to hear when I call a company with a failure example, but I digress). I asked about the instructions and said I was a bit confused between the emphatic written instructions and the video, which were contradictory. He said that the written instruction way (slit side aft) was really only recommended for 20 hp and under engines (but I did not see that anywhere, just that these were "the" instructions for the Universal Wedge). So, he recommended I use it with the hard rubber aft (which did work fine for 6,000 miles and does seem more logical to me after having seen the failure). I asked if he could send me a new wedge, because mine had taken a set in the deformed position, and even though it straightened out about 80%, I still didn't trust it as much as I would a new one. He was amenable, although I didn't ask if I would be charged and he didn't specify one way or the other. I'm hoping/assuming it will be gratis. I offered to send him photos of the problem I had, and he was interested in them, which I'm glad about. He was pleasant to talk to on the phone.

So (if anyone is still here and awake :wink: ), when I got to where I was picking up a friend, I took out the now-gracefully-failing Bed Slat 2.0, and put the semi-healed M-Y Wedge back in the way I had it the first time (solid rubber aft). Since it still had a slight memory of the deformation (basically it gets out of column and can easily continue to deform), I took some disused hose clamps and placed them around the wedge at about the half way point, where the deformation had been. I figured all they had to do was help to keep it in column. I have about 400 miles on that setup now, and that was over some pretty bouncy off-interstate highways, and all looks fine. I think I would now trust a new wedge (that had not ever deformed) if it were placed with the solid rubber aft. In fact, I will use the new wedge when I get it.

The last note is that M-Y say you can trim the wedge to make it fit or to put the motor on a better angle for your setup. I did trim around 1" off the height of the wedge when I got it, because my engine already protrudes a fair bit past the taillights, and the more it is tilted up the MORE it protrudes. It's possible that as the engine is slightly less tilted it puts more forward pressure on the wedge, but then that still rode absolutely fine when I had it the "wrong" way with the solid rubber aft.

I'll post back to my "wedge failure" thread when I hear back from the fellow at M-Y after he has seen my photos. If it did fail because of the slit being forward (seems like that can allow the motor to push it off the trim shaft and or get it out of column), then I hope they clarify that those instructions are only for small (< 21 hp) engines. I'm hoping my engine tilt mechanism wasn't damaged. It seems to work fine on the trailer, but that's a limited amount of use.

Sunbeam
 
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