I am restoring a 1977 19' I/O that has a Mercruiser MC-1 outdrive and transom assembly. Eventually I would like to upgrade the entire drive system to Alpha 1 Gen II but the budget isn't there to do the whole thing right now. But with the transom torn apart I'd like to do as much as possible now without having to go back later and remove the engine to tackle the transom assembly once again.
So far, I've removed the old tired 305 and entire MC-1 transom assembly.
Made sure transom was checked and repaired as necessary to be rock solid. This is done.
Spent months trolling ebay gathering the necessary good used parts.
I've got an upgraded 350 engine ready to install, single rear main seal, 14" flywheel, newer style flywheel housing (9.5" bolt spacing), triangular coupler. Equivalent to Mercruiser's 260.
Next I am replacing the old old pre-alpha inner transom plate (15" bolt spacing) with a newer alpha 1 gen i/ii inner transom plate (9.5" bolt spacing).
Now what I also want to do is to mount an Alpha 1 Gen II outer transom assembly and be able to mount my existing MC-1 outdrive on it so I can continue to use the boat until I gather enough budget together to finally buy a new SEI 116 drive for it which then would give me an entire Alpha 1 Gen II drive system.
I've read dozens of posts of people wanting to do either this or something similar. Most of the time the answer they get is too many things don't exactly fit. So what I want to do is try to figure out if there are ways to engineer a solution to each of the problems of being able to get this to work.
From all the readings its seems like these are the main problems mating Gen I drive to Gen II transom assy:
1. shift shaft
The Gen I uses an upper, intermediate and lower shift shaft arrangement.
The Gen II uses just an upper and lower shift shaft arrangement.
I have a very good machinist.
Would it not be possible to fabricate a new intermediate shift shaft that would allow a MC-1/Gen I to mate to a Gen II upper shift shaft?
2. trim cylinders
Gen I trim cylinder mounting width is narrower and the piston is longer compared to Gen II.
Would an Anchor Rod Kit for a Gen II plus some fabricated SS spacer bushings create the proper alignment on the Gen I outdrive?
Would the Gen II trim cylinders work as is or would you need to take the piston out of the Gen I trim cylinders and use them in the Gen II trim cylinders to get them to work with the Gen I outdrive?
3. drive oil passage
install Gen II line and oil reservoir for future use but block off both ends of reservoir line since no connection at Gen I outdrive.
4. speedometer tube
Install but block off outer connector since no connection on Gen I lower unit.
What do you think? Doable?
So far, I've removed the old tired 305 and entire MC-1 transom assembly.
Made sure transom was checked and repaired as necessary to be rock solid. This is done.
Spent months trolling ebay gathering the necessary good used parts.
I've got an upgraded 350 engine ready to install, single rear main seal, 14" flywheel, newer style flywheel housing (9.5" bolt spacing), triangular coupler. Equivalent to Mercruiser's 260.
Next I am replacing the old old pre-alpha inner transom plate (15" bolt spacing) with a newer alpha 1 gen i/ii inner transom plate (9.5" bolt spacing).
Now what I also want to do is to mount an Alpha 1 Gen II outer transom assembly and be able to mount my existing MC-1 outdrive on it so I can continue to use the boat until I gather enough budget together to finally buy a new SEI 116 drive for it which then would give me an entire Alpha 1 Gen II drive system.
I've read dozens of posts of people wanting to do either this or something similar. Most of the time the answer they get is too many things don't exactly fit. So what I want to do is try to figure out if there are ways to engineer a solution to each of the problems of being able to get this to work.
From all the readings its seems like these are the main problems mating Gen I drive to Gen II transom assy:
1. shift shaft
The Gen I uses an upper, intermediate and lower shift shaft arrangement.
The Gen II uses just an upper and lower shift shaft arrangement.
I have a very good machinist.
Would it not be possible to fabricate a new intermediate shift shaft that would allow a MC-1/Gen I to mate to a Gen II upper shift shaft?
2. trim cylinders
Gen I trim cylinder mounting width is narrower and the piston is longer compared to Gen II.
Would an Anchor Rod Kit for a Gen II plus some fabricated SS spacer bushings create the proper alignment on the Gen I outdrive?
Would the Gen II trim cylinders work as is or would you need to take the piston out of the Gen I trim cylinders and use them in the Gen II trim cylinders to get them to work with the Gen I outdrive?
3. drive oil passage
install Gen II line and oil reservoir for future use but block off both ends of reservoir line since no connection at Gen I outdrive.
4. speedometer tube
Install but block off outer connector since no connection on Gen I lower unit.
What do you think? Doable?
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