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MPR FAB
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You want the pump and motor parallel but at different hight to get a 2 deg angle on the h-bar. Looking at the pic set the motor 1/8in higher then the pump and start there. That should get to close and adjust from there. Hope this helps
 

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Way to much "kink" , the depth engagement looks OK on the yoke but the rear needs to drop an/or the front likley come up , possibly your Pan ? your not trying to use the V-drive pan you had I hope ? tom
 

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Living in a cage of fear
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It appears that the rear of the Engine needs lowered to make the centerlines parallel, and after that possibly the entire engine lowered squarely to get the proper angle offset?

If one of the pros could correct me if I am wrong that would be great, I don't want to do it wrong either!:)hand



The angle showing 2* would actually be 88* the way I drew it, or 2* off of 90*.

The actual 2* would off of the centerline.
 

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And I could be wrong... but it looks like the front of the motor needs to come way up...from this side of my computer screen.:)sphss
 

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Not trying to stir anything up but technically the angle between the H-bar and the crank and the H-bar and the pump shaft need to be the same. See attached picture. The pump shaft and the engine crank do not have to be parallel. It is the angles to the H-bar that have to be the same. 1 1/2 degrees is good rule of thumb. Some boats will have a little more and some a little less. 3 degrees is getting pretty high and you would want at least 1/2 degree. Good luck.
 

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Amerian Turbine Man
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Drive Line

In a perfect set-up the pumpshaft and crankshaft would be parallel but, offset .060-.080".
Ron
 

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Living in a cage of fear
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Living in a cage of fear
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Not trying to stir anything up but technically the angle between the H-bar and the crank and the H-bar and the pump shaft need to be the same. See attached picture. The pump shaft and the engine crank do not have to be parallel. It is the angles to the H-bar that have to be the same. 1 1/2 degrees is good rule of thumb. Some boats will have a little more and some a little less. 3 degrees is getting pretty high and you would want at least 1/2 degree. Good luck.
That is interesting, I never knew that.
Why is that anyway?
Does it create vibration or something if they are not parallel or equal angles?
 

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Broke Member
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Discussion Starter #16
got it!

Sorry i didnt get back to you guys sooner on this. Got a little tied up but i did get it squared away. Appreciate all of your help guys. It's good to know there's always somewhere I can turn for a quick answer. This is what I wound up with
 

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That is interesting, I never knew that.
Why is that anyway?
Does it create vibration or something if they are not parallel or equal angles?
Per fastmarlene's picture, the angles have to be the same to keep each end of the assembly in-phase as the joints revolve. U-joints are not constant-velocity devices, and the perimeter of each joint accelerates and decelerates as it rotates. To minimize vibration and fatigue issues, the accel/decel cycles at each end have to be in-phase. This is accomplished by keeping the angles the same. Per the picture, there are two ways to do this.

Hope this helps.

Matt
 

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Living in a cage of fear
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Per fastmarlene's picture, the angles have to be the same to keep each end of the assembly in-phase as the joints revolve. U-joints are not constant-velocity devices, and the perimeter of each joint accelerates and decelerates as it rotates. To minimize vibration and fatigue issues, the accel/decel cycles at each end have to be in-phase. This is accomplished by keeping the angles the same. Per the picture, there are two ways to do this.

Hope this helps.

Matt
Thanks!

So to "work" both ends evenly and in phase is what it amounts to?

Question: If everything is in line vertically, with no "offset", the angle can also be achieved laterally?
Like if the jet or engine was slightly off center in the boat?

I realize that would not be "optimum", but strictly speaking of U-joints, it wouldn't care how that offset was achieved?

I have the 2* or so vertically in the Miller, but the engine is ever so slightly off center, like less than a 16th of an inch.
 

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Right on about the u-joints not being constant velocity. The angle of articulation between the engine and the H-bar results in the H-bar speeding up and slowing down twice every revolution of the engine. By matching that angle between the H-bar and the pump and keeping the spiders in phase (lined up with each other) the speed changes are cancelled out and the pump should see the same speed as the engine is turning. The angle can be up down, side to side or a combination just as long as it is the same. From a common sense approach I am not sure just how much affect a 1/4 degree difference makes in the real world. I do know if the difference becomes significant you will be putting stress on something in the drive line. Guessing in most cases the weak point is the u-joints themselves.
 
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