tbear1964
Petty Officer 3rd Class
- Joined
- Mar 4, 2007
- Messages
- 94
Okay, I have done some forum searches and looked at 2 PDF's from the Adults Only section. I'm still a bit confused and could use some clarification (I miss Volvos, lol)
I have an 85 Cobalt, 260 Mercruiser Alpha outdrive. I thought it was a Gen 1, but apparently an MR by serial number. #A334758 1.50 R 1.50:1 and RH rotation.
Question 1: can any R, MR, and Alpha One Gen 1 with a 1.50:1 RH replace it?
If not, which drives or serial number ranges?
With my new found knowledge, I'm now a bit leery and serial number obsessed.
I have a line on an 83-84 Sea Ray drive from a 228 4 bbl, with a 1:50 RH, but it looks like a 78-82, based on it's ser. # 6070301. Compatible? It's not necessary, but a good deal. I have a line on a few others in my budget.
Reference pics of my drive/transom: the drive was in a hot marina for 20 years and the case is pitted. Also the upper drive shaft seals were bad and there was minimal "oil" when I drained it after the season. Thus the drive replacement.




Thanks for any info. I'd like to clear this up by the weekend so I can work on it. Ted
I have an 85 Cobalt, 260 Mercruiser Alpha outdrive. I thought it was a Gen 1, but apparently an MR by serial number. #A334758 1.50 R 1.50:1 and RH rotation.
Question 1: can any R, MR, and Alpha One Gen 1 with a 1.50:1 RH replace it?
If not, which drives or serial number ranges?
With my new found knowledge, I'm now a bit leery and serial number obsessed.
I have a line on an 83-84 Sea Ray drive from a 228 4 bbl, with a 1:50 RH, but it looks like a 78-82, based on it's ser. # 6070301. Compatible? It's not necessary, but a good deal. I have a line on a few others in my budget.
Reference pics of my drive/transom: the drive was in a hot marina for 20 years and the case is pitted. Also the upper drive shaft seals were bad and there was minimal "oil" when I drained it after the season. Thus the drive replacement.




Thanks for any info. I'd like to clear this up by the weekend so I can work on it. Ted