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Author Topic:   Twin Engine Propeller Shaft Alignment

modeseven posted 06-12-2006 04:47 PM ET (US)
I have a 1985 REVEGNE 22 with twin 140-HP motors.The motors are not counter rotating. They each spin to the right. I was told that in my case I need to adjust the motors so that they are each pointed in the outward position. Is this true? Or should I just have them aligned straight? If it is true, what is the purpose of having them pointed outwards?
Buckda posted 06-12-2006 05:44 PM ET (US)
modeseven -
Having just learned about this when I installed non-counter-rotating 90's on my Outrage this spring, I'll try to give you an answer.
What you are describing is the "toe in" - "toe-out" alignment.
You want your motors to be about 3/4 to 1 inch "toe-in", meaning that the distance between the "noses" of the "bullets" on your gearcases should be 3/4 to 1 inch closer together than the prop shaft.
To do this adjustment, you must first remove the props, then remove the tie-bar from one engine. Align the motors and adjust the tie-bar accordingly.
Tom W Clark posted 06-12-2006 06:27 PM ET (US)
For twin engine Whalers the normal amount of toe recommended by Boston Whaler is 1/2" - 3/4" of Toe-In. It does not matter if the motors are counterrotating or not.
Dave's boat might be a little different than most because of his set back brackets. Normally you needn't disconnect anything. On my Revenge 25 you loosen the locking nuts and spin the turnbuckle-like portion of the tie bar until you have achieved the desired amount of toe.
Under no circumstances should you need to remove the propellers.
Buckda posted 06-12-2006 06:31 PM ET (US)
I suppose I should clarify:
Removing the propellers may make the measuring process easier.
The teleflex tie-bar I have requires removal on one side to achieve this adjustment.
modeseven posted 06-12-2006 06:45 PM ET (US)
[T]hanks[,] [T]om. [Your suggestion] makes perfect [sense]. [I] will just turn the tie bar until the motors are where [I] want them. [T]hanks for the help.
Tom W Clark posted 06-12-2006 06:54 PM ET (US)
For measuring the on-center (o.c.) distance between the propellers, you can use any reference point you want, it needn't be the middle of the propeller shafts.
The o.c. distance will always be the same if you choose the same spot on each prop. I just measure from one side of the hub on one prop to the same side of the hub on the other prop. This way I can "hook" my tape measure there.
modeseven posted 06-12-2006 08:04 PM ET (US)
Give me a recommedation for outboard brackets.
jimh posted 06-12-2006 08:14 PM ET (US)
Installation of twin engines on moderate V-hull boats such as a classic Boston Whaler is discussed in my article in the REFERENCE section. See:
Twin Engine Mounting
http://continuouswave.com/whaler/reference/twinEngineMounting.html
The article mentions considerations for toe-in or toe-out when aligning the propeller shafts of the twin engines.
jimh posted 06-12-2006 08:17 PM ET (US)
There is a follow-up discussion thread linked from the REFERENCE article. It discusses more on toe-in and toe-out. See:
http://continuouswave.com/ubb/Forum4/HTML/004507.html
jimh posted 06-12-2006 08:19 PM ET (US)
For a comprehesive article on engine setback brackets, see:
Engine Brackets
http://continuouswave.com/whaler/reference/engineBrackets.html
There is a list of engine bracket manufacturers and links to more information about their brackets.
jimh posted 06-12-2006 08:22 PM ET (US)
The RITE-HITE bracket looks like a nice design and has a modest price. You can see these in the CETACEA PAGE 81 article:
April 16, 2006
GAMBLER--On A Roll
Twin E-TEC 90-HP Re-power OUTRAGE 18
http://continuouswave.com/whaler/cetacea/cetaceaPage81.html
modeseven posted 06-13-2006 10:33 PM ET (US)
[I] just tried to put on the tie bar and [it is] way [too] big and long. [I]t must be at least 6-inches [too] big. [C]an [I] cut a section out of the middle and then weld it back together?
bsmotril posted 06-14-2006 11:25 AM ET (US)
I don't see why not. But they can be bought in various lengths. You might try exchanging it for the correct one.
Buckda posted 06-14-2006 02:16 PM ET (US)
What brand is it?
If it is a Teleflex, you should be able to remove the end fitting and cut it from the end so you will not have to weld anything.
Voice of experience talking, don't cut anything until you are sure what you're doing.
Dave
jimh posted 06-14-2006 08:15 PM ET (US)
I cannot imagine that the makers of an adjustable tie-bar kit intended that the user have to resort to cutting and welding to make adjustments.
modeseven posted 06-15-2006 06:56 AM ET (US)
the tie bar was given to me.it was made for motors that are mounted far away from each other.my twins are real close.iam going to take the tie bar apart,then see if it can just be cut.if not i will take a section out of the middle and then weld it back together.i will let you guys know how it worked out.

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Author	Topic: Twin Engine Propeller Shaft Alignment
modeseven	posted 06-12-2006 04:47 PM ET (US) I have a 1985 REVEGNE 22 with twin 140-HP motors.The motors are not counter rotating. They each spin to the right. I was told that in my case I need to adjust the motors so that they are each pointed in the outward position. Is this true? Or should I just have them aligned straight? If it is true, what is the purpose of having them pointed outwards?
Buckda	posted 06-12-2006 05:44 PM ET (US) modeseven - Having just learned about this when I installed non-counter-rotating 90's on my Outrage this spring, I'll try to give you an answer. What you are describing is the "toe in" - "toe-out" alignment. You want your motors to be about 3/4 to 1 inch "toe-in", meaning that the distance between the "noses" of the "bullets" on your gearcases should be 3/4 to 1 inch closer together than the prop shaft. To do this adjustment, you must first remove the props, then remove the tie-bar from one engine. Align the motors and adjust the tie-bar accordingly.
Tom W Clark	posted 06-12-2006 06:27 PM ET (US) For twin engine Whalers the normal amount of toe recommended by Boston Whaler is 1/2" - 3/4" of Toe-In. It does not matter if the motors are counterrotating or not. Dave's boat might be a little different than most because of his set back brackets. Normally you needn't disconnect anything. On my Revenge 25 you loosen the locking nuts and spin the turnbuckle-like portion of the tie bar until you have achieved the desired amount of toe. Under no circumstances should you need to remove the propellers.
Buckda	posted 06-12-2006 06:31 PM ET (US) I suppose I should clarify: Removing the propellers may make the measuring process easier. The teleflex tie-bar I have requires removal on one side to achieve this adjustment.
modeseven	posted 06-12-2006 06:45 PM ET (US) [T]hanks[,] [T]om. [Your suggestion] makes perfect [sense]. [I] will just turn the tie bar until the motors are where [I] want them. [T]hanks for the help.
Tom W Clark	posted 06-12-2006 06:54 PM ET (US) For measuring the on-center (o.c.) distance between the propellers, you can use any reference point you want, it needn't be the middle of the propeller shafts. The o.c. distance will always be the same if you choose the same spot on each prop. I just measure from one side of the hub on one prop to the same side of the hub on the other prop. This way I can "hook" my tape measure there.
modeseven	posted 06-12-2006 08:04 PM ET (US) Give me a recommedation for outboard brackets.
jimh	posted 06-12-2006 08:14 PM ET (US) Installation of twin engines on moderate V-hull boats such as a classic Boston Whaler is discussed in my article in the REFERENCE section. See: Twin Engine Mounting http://continuouswave.com/whaler/reference/twinEngineMounting.html The article mentions considerations for toe-in or toe-out when aligning the propeller shafts of the twin engines.
jimh	posted 06-12-2006 08:17 PM ET (US) There is a follow-up discussion thread linked from the REFERENCE article. It discusses more on toe-in and toe-out. See: http://continuouswave.com/ubb/Forum4/HTML/004507.html
jimh	posted 06-12-2006 08:19 PM ET (US) For a comprehesive article on engine setback brackets, see: Engine Brackets http://continuouswave.com/whaler/reference/engineBrackets.html There is a list of engine bracket manufacturers and links to more information about their brackets.
jimh	posted 06-12-2006 08:22 PM ET (US) The RITE-HITE bracket looks like a nice design and has a modest price. You can see these in the CETACEA PAGE 81 article: April 16, 2006 GAMBLER--On A Roll Twin E-TEC 90-HP Re-power OUTRAGE 18 http://continuouswave.com/whaler/cetacea/cetaceaPage81.html
modeseven	posted 06-13-2006 10:33 PM ET (US) [I] just tried to put on the tie bar and [it is] way [too] big and long. [I]t must be at least 6-inches [too] big. [C]an [I] cut a section out of the middle and then weld it back together?
bsmotril	posted 06-14-2006 11:25 AM ET (US) I don't see why not. But they can be bought in various lengths. You might try exchanging it for the correct one.
Buckda	posted 06-14-2006 02:16 PM ET (US) What brand is it? If it is a Teleflex, you should be able to remove the end fitting and cut it from the end so you will not have to weld anything. Voice of experience talking, don't cut anything until you are sure what you're doing. Dave
jimh	posted 06-14-2006 08:15 PM ET (US) I cannot imagine that the makers of an adjustable tie-bar kit intended that the user have to resort to cutting and welding to make adjustments.
modeseven	posted 06-15-2006 06:56 AM ET (US) the tie bar was given to me.it was made for motors that are mounted far away from each other.my twins are real close.iam going to take the tie bar apart,then see if it can just be cut.if not i will take a section out of the middle and then weld it back together.i will let you guys know how it worked out.