Engine alignment questions
#1
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From: Sun Prairie, WI
I’m going through engine alignment in a pair of alpha drives. I’m noticing the witness marks in top of my alignment bar, but not much on the bottom. I’m trying to envision in my head which direction I need to move the front mounts. I think I’d need to lower the front of the engine. Is this correct to get witness marks in the bottom as well? Or am I think the opposite?
#2
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From: Mason, Ohio
You need to raise the engine in the front if you see that your alignment tool is touching the top of the coupling.
If you are getting the tool in all the way and see the marks on top and nothing on bottom, you are close. Count the turns... and do both the same.
If you are getting the tool in all the way and see the marks on top and nothing on bottom, you are close. Count the turns... and do both the same.
#3
Did you rotate the gimbal bearing up and down and side to side in it's housing and then push the tool in hard to align the bearing to the engine. It might be that the bearing is just stuck in a direction that forces the tool to the top. I always move the bearing around then center it.
#4
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From: Sun Prairie, WI
#6
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From: Sun Prairie, WI
So I was checking alignment on my 502/bravo drive and have a few questions for the experienced folks. I found that on the alignment bar, I was getting the greased rubbed oof from the splines predominantly on the bottom. Top side had some marks, but not as much. So I raised the front of the engine 2 turns on f the nut on each side. About 2mm with. The grease pattern didn’t change a ton. Should it for that amount of adjustment? I locked it down and didn’t go anymore on the adjustments. The bar does go in pretty easy and bottoms out well. Just wasn’t comfortable going anymore with raising the front of the engine from where it was at.
#7
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From: Mason, Ohio
If you see more of a spline pattern on one side and some spline pattern on the other, Try half a turn more of the nut on both sides. Check. You are so close you are safe to button up.
if you are saying the one side has no marks, keep adjusting.
Did you put a new gimbal bearing in? If you did....put the alignment tool all the way in and hit the end of that tool from bottlom, top, left and right to ensure that bearing is squared up. Then check the alignment.
Chris
if you are saying the one side has no marks, keep adjusting.
Did you put a new gimbal bearing in? If you did....put the alignment tool all the way in and hit the end of that tool from bottlom, top, left and right to ensure that bearing is squared up. Then check the alignment.
Chris
#8
Engine alignment gets real crazy when you add an extension box and big HP.
The tool should be able to be pulled back out from bottomed with two fingers. Anything more than that and it isn't aligned.
As I have said many times in the past if you have to make major changes check the rear mounts. They can sag with time and the constant grease bath.
The tool when properly aligned should be parallel to the running surface on the bottom of the boat.
I have had to shim up the rear mounts to get there.
I am using solid front mounts and have used shims and multiple layers of fender washers with shorter rear bolts in order to lock the rear mounts from moving.
I don't care about or feel any vibration at all.
The tool should be able to be pulled back out from bottomed with two fingers. Anything more than that and it isn't aligned.
As I have said many times in the past if you have to make major changes check the rear mounts. They can sag with time and the constant grease bath.
The tool when properly aligned should be parallel to the running surface on the bottom of the boat.
I have had to shim up the rear mounts to get there.
I am using solid front mounts and have used shims and multiple layers of fender washers with shorter rear bolts in order to lock the rear mounts from moving.
I don't care about or feel any vibration at all.
#9
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From: Sun Prairie, WI
If you see more of a spline pattern on one side and some spline pattern on the other, Try half a turn more of the nut on both sides. Check. You are so close you are safe to button up.
if you are saying the one side has no marks, keep adjusting.
Did you put a new gimbal bearing in? If you did....put the alignment tool all the way in and hit the end of that tool from bottlom, top, left and right to ensure that bearing is squared up. Then check the alignment.
Chris
if you are saying the one side has no marks, keep adjusting.
Did you put a new gimbal bearing in? If you did....put the alignment tool all the way in and hit the end of that tool from bottlom, top, left and right to ensure that bearing is squared up. Then check the alignment.
Chris



