Alpha one Gen 2 SEI 116. upper 1.42 ratio possible failure

[pecothern]

I installed my upper and lower as a cobra conversion about 3 1/2 years ago. Ive been very happy with it. The oil was dark after the break-in I called SEI and they recommend a drive shower. I installed it. The oil still looked a bit dark to me each year it changed it. There was a little metal on the drain plug but nothing terrible. Yesterday it started making a whoop whoop whoop sound and I felt a vibration. Its way louder in forward or reverse than neutral. When I pulled it out of the water it sounds like and feels like the sound is coming from the upper. I pulled the top off tonight and surprisingly the gears look fine. The horizontal gear is wobbling all over the place. I'm not sure if the amt of wobble is normal with the top bearing race off. It sure seems like the lower part of that gear is very loose which would explain the gear misalignment and the noise. Please watch my youtube video https://youtu.be/ltDiJPW9FAw and tell me what you think. I'm inclined to buy a new upper. I know this one is out of warranty. Thanks for your help.

 

[porscheguy]

That movement is normal. It’s held in place when the cap is installed and torqued down properly.

 

[alldodge]

I also don't see any issues.

The shaft is held within specs from the bearing on top and bottom. To remove the top and wiggle the shaft does not indicate there is an issue. To verify there are no issues you need to get the manual and go thru the preload and shimming processes.

Have much play up/down/in/out on the drive shaft?
Is the alignment correct?
Gimbal bearing smooth?
How about the U joints?

 

[pecothern]

Thanks everyone for quick reply! A few answers to questions I've been asked

Have much play up/down/in/out on the drive shaft?

I assume we are talking about the donkey d**k? It seems good and tight with no wobble. I did replace the U-joints a few months ago , they were clicking when turning left and right. It occurred to me banging on the joints might could have damaged that bearing. But it seems fine. I have ordered one of those huge spanner wrenches to pull that part out so I can properly evaluate that lower bearing on the horizontal gear.

Is the alignment correct? Yes I confirmed that when I replaced the u joints a few months ago, but I suppose I need to recheck it.

Gimbal bearing smooth? I replaced the gimble bearing a few months ago along with the U-joints and it seems smooth now.

 

[alldodge]

Have much play up/down/in/out on the drive shaft?

I assume we are talking about the donkey d**k?

Question for movement was drive shaft and yoke, not the shaft inside the drive. So were good

 

[harringtondav]

The vertical drive pinion will wobble w/o the top cap to support it, and is normal. But you said horizontal gear, which is the input gear. This gear should have zero movement because the two monster Timken tapered roller sets are pre-loaded.

So if this is the loose gear, stop now before real, expensive problems follow. You'll need to pull the drive, remove the castle retaining ring and pull the whole drive shaft assy. This pre-loading process is one of the most critical in the drive.

If you don't have a manual, you tube the process. If you don't get it right, the assy. won't fit back into that slip fit hsg. bore, and you could tighten above the 5-7 inch lb rolling drag spec. Then you may see bearing failure.

 

[pecothern]

The gear on the vertical shaft is the one that was wobbling In the end I just bought a new upper and Lower from SEI .I disassembled the old upper completely and could find nothing obviously wrong. I ordered the tool to take apart the lower but havent taken it apart yet. I have the new upper and lower installed and I'm breaking it in now.

 

[greno]

You might have just a bad U-joint. If you don't have a lot of metal on the magnet then I don't think you have anything seriously wrong with the outdrive.