Singles versus Twins

Charlie,

As payment for my past sins, many of "my" products are incorporated in brand new airplanes which take off, make a left turn, and fly over my house many times per day :shock:
Don't start me on my favourite soapbox, it runs through several bottles of wine.

But, if your car or boat had the same despatch reliability as a modern airplane, you would sell it quickly.

Cheers,

Merv
 
rogerbum":mbv7rxc3 said:
However, I will point out that there were a couple of times, I launched my 22 to discover after untying that the mechanical steering had seized due to no use for a few months. That's really uncomfortable after you've pushed off a dock and are adrift in a current. On a couple of occasions, brute force released it. But after that, I learned to check my steering before pushing off and to move the engines every month or so during storage.
Click to expand...
Click to expand...

The USCG requires a commercial captain to test the steering by turning from lock to lock prior to getting underway. Woe to the captain who forgets and casts off with no steering!
 
Larry H":r2eafb05 said:
rogerbum":r2eafb05 said:
However, I will point out that there were a couple of times, I launched my 22 to discover after untying that the mechanical steering had seized due to no use for a few months. That's really uncomfortable after you've pushed off a dock and are adrift in a current. On a couple of occasions, brute force released it. But after that, I learned to check my steering before pushing off and to move the engines every month or so during storage.
Click to expand...
Click to expand...

The USCG requires a commercial captain to test the steering by turning from lock to lock prior to getting underway. Woe to the captain who forgets and casts off with no steering!
Click to expand...

Since this is Singles vs Twins, I just can't resist. This Lock to lock check -- a good idea, especially for a singles system. It has not been my practice to even turn the wheel until I am out of the marina :shock: but then with the twins hanging out on back, the low speed steering is done with the differential throttling or unilateral forward and reverse control. :crook Looks like now there is something else to add to the pre trip check list. Good heads up, Thanks.

Harvey
SleepyC :moon

JC_Lately_SleepyC_Flat_Blue_055.highlight.jpg
 
Harvey, a quick question. How much toe in do you run on your outboards?
 
I'd skip the Teleflex system and go straight to a Voith Schneider Propeller:

http://en.wikipedia.org/wiki/Voith_Schneider_Propeller

They make them for large ships and tugs, and there's a tiny version for RC models, so we just need something in between! :)

Of course, the draft wouldn't be 8 inches anymore...
 
I do know there is such a thing, but I don't know how much mine are set at. In talking with my mechanic, if I remember right, because the twins are very close together comparatively, I don't recall that "toe in" would make any difference.

I'm open to learning more on it. Affect on vessel, with and without, and anything else important, I guess.

Harvey
SleepyC :moon
 
I have twin 80's on my CD25, the toe-in is set for 3/16" at the front steering bar that joins the two motors. That is the number I was given when I took delivery of the boat, and have kept it there (repaired the slave steering cylinder once, requiring removal). Not sure how critical this is or even if it affects the operation/steering.
 
Larry H":2y2xbfht said:
rogerbum":2y2xbfht said:
However, I will point out that there were a couple of times, I launched my 22 to discover after untying that the mechanical steering had seized due to no use for a few months. That's really uncomfortable after you've pushed off a dock and are adrift in a current. On a couple of occasions, brute force released it. But after that, I learned to check my steering before pushing off and to move the engines every month or so during storage.
Click to expand...
Click to expand...

The USCG requires a commercial captain to test the steering by turning from lock to lock prior to getting underway. Woe to the captain who forgets and casts off with no steering!
Click to expand...

This captain now requires it too. But I learned it the hard way and it took me two lessons (I'm a slow learner).
 
My boat came with 1/4" toe out, measured at the nose cones and propeller shafts. It was difficult to maintain course at that setting. After changing it to 3/16" toe in it handles much, much better. Thing is, I haven't tried fine tuning it and it is possible there is a better setting.
 
Pretty hard to measure on a TC255. We have a "liquid tie bar" which allows an almost infinite toe in toe out setting. Our engines are VERY far apart compared with a usual twins setup.

Come to think of it, maybe control of that connection could do a partial Optimus 360 trick!!
 
Two words--Lightning Strike--either direct, or nearby in the water. All systems are out! I see it happen frequently down here in Florida.

I know of one at least one large Nordhavn which was totally disabled by systems electronic failure. (There is suspicion that a second one also had this and was the cause of its loss). These are very high end yachts which cost millions of dollars, and should have back up systems.
 
This is the first time I have noticed a discussion on "toe-in" for twins. I have never been happy with the steering on my 22, it bears to starboard. I changed the tabs on the engine and it helped but still not correct. Does anyone know the correct toe-in for twin honda 35's, 40's, or 50's?
 
lloyds":2qqiabod said:
I have never been happy with the steering on my 22, it bears to starboard. I changed the tabs on the engine and it helped but still not correct.
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I assume you have twins?
Dues the boat sit level, side to side, with everyone aboard?
Are the props identical? Does one, or both, have hidden damage. Have you tried switching them?
Are both tachometers accurate? Are you reading them accurately (parralax?)?
Does the steering system need maintenence?
Try 3/16" toe in.
Keep after the tabs.
Make one change at a time so's you can identify and isolate problems.
I'm not an expert, this is just me thinking out loud.
 
Chester, according to his profile, he has twin 35's.

Maybe the port one got switched with a 45 and just LOOKS like a 35??

:shock: :lol: :roll:

Charlie
 
The other issue can be that you have two right hand motors--which is quite likely. You may need more trim tab correction.
 
thataway":3q28f3rm said:
The other issue can be that you have two right hand motors--which is quite likely. You may need more trim tab correction.
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From earlier remembrances, there are no outboards under 100 HP (I believe that is the HP cut off) that are available as counter clockwise, and I do know that our twin 50 HP Johnson (Suzuki under a Johnson cover) are clockwise rotating. I don't know the amount of "toe-in" on ours, but most certainly there is obvious trim tab correction. I've never noticed any "off steering" tendency on Sea Shift. I remember when Les at EQ Marine took me out on the "shake-down" cruise, that was one of many things he checked out for the proper set up.
 
According to Les, Honda only makes left hand motors at 90hp and up so all of us with smaller Honda twins have right hand motors.
 
I certainly would not be one to argue with Les, but my Honda 90 swings a right hand prop. Most single engine boats run right hand props.

Mercury makes a 90 hp counter rotating lower unit. There were some counter rotating engines back in the late 80's Not sure that there are any true counter rotating outboard currently.
 
My engines are the same, and I am pretty sure they are right hand. I have tried to even out every other possible cause. I ended up adjusting with the tabs on the engines and got most of it out but it seems like with about 20 degrees of adjustment in the tabs it doesn't make for the most efficieint running. I might try the 3/16 toe in and see what that does.
 
As I have a single 115 and kicker it really does not pertain to me, but I am interested. How do you adjust "toe" on an outboard? Thanks
 
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