OMC lower unit same as Johnson?

[Cyclone_Mark]

I recently destroyed the lower unit of my 1990 OMC Cobra 2.3L on a rock. I found a used Johnson 90 HP lower unit in my area, and it looks like it might fit. I looked in the GLM Marine catalog for some comparisons. The overall case dimensions match exactly, and the pictures look identical. The GLM part numbers are not the same, however, and the exploded diagrams looks a little different. Many of the part numbers match, but just as many part numbers are slightly different. It looks like the water pump and shift lever are a little different.

If the aluminum casting is identical, that might work, too. The entire lower unit is priced less than the quote to repair the skeg.

Does anyone know how much OMC and Johnson gear cases may have in common?

Also, to clarify on some earlier posts, I'll have to remove the complete upper and lower assembly from the stern before separating the lower from the upper, right?

 

[Howard Sterndrive]

Re: OMC lower unit same as Johnson?

they are not the same, not compatible in any way. they do look quite similar from a few feet away. They also share some gears in some ratios..(although that might be the larger V6 outboards vs. 800 size cobra lowers)
Instead of the GLM catalog of aftermarket "will fit" parts, you can look at the actual original OMC parts book at shop.evinrude.com - you can compare exploded views and part numbers line by line.
outboard gearcases shift differently, and have water pumps

yes, you have to remove the drive to remove the lower from a Cobra.

 

[HT32BSX115]

Re: OMC lower unit same as Johnson?

Instead of the GLM catalog of aftermarket "will fit" parts, you can look at the actual original OMC parts book at shop.evinrude.com - you can compare exploded views and part numbers line by line.

You can also go to http://epc.brp.com