20 yr old alpha gen II transom rebuild or buy new

I am needing advice on best way to proceed. I have water coming in transom and it is now rotten. Boat transom being rebuilt. The question is what to do with the transom/gimbal assembly? It is the older gen II design with the lower carriage bolts going thru the transom plate(It appears water was coming thru lower bolt area and 1 bolt cracked when removed). I noticed the new design has studs. Wondering if I should buy a new outer transom plate, rebuild what I have, or buy a whole new transom assembly because of the time, tools, and parts cost needed get it done right. I noticed the sender unit wires are cracked and insulation is missing. I had the bellows and gimbal bearing replaced 2-3 yrs ago. I have never done anything to the lift cylinders. Assembly has some corrosion which will need to be repaired as well but not too bad. I clean and repaint every year. The boat is in the water full time from May thru September. I want to make sure to not have any water leak problems and don't want to have to pull motor and take it all apart any time soon. Any help would be appreciated.

Re: 20 yr old alpha gen II transom rebuild or buy new

hi....welcome to iboats !

im not quite sure if i follow you....

you say you have an older alpha one gen 2.

are you sure that isnt the older alpha style and not a gen2?

can you post pics of the drive?

the reason im asking is that the gen2 is the current model used on most small watercraft.
this will mean that you are asking to buy what you already have !

the difference between the studs and bolts is just that someone has stripped the studs and replaced them with bolts...
that is an easy fix.

however.....the guys in this forum (the dry dock) are more tilted towards fiberglass repairs and alum reevit bashing.

so im going to move this to where you will get more response from many a merc tecks !

Re: 20 yr old alpha gen II transom rebuild or buy new

Alpha I Gen II transom shields do not use thru bolts on the lower 2 bolts, they used studs.

Do not go by the year of your boat as the year of your drive. MANY 91 boats have 90 drives, and they are not Gen II.

Pictures or serial numbers of the drive are a must at this point.

Re: 20 yr old alpha gen II transom rebuild or buy new

OK here is the serial numbers:
Engine: OD810417
Transom: OD771209
Drive: OD687114

I have also attached some pics for better description. Thanks for your help! Again, looking for recommendation of rebuild, replace specific parts, or buy new assembly. Also any manuals/tools needed would be appreciated. Thanks

Re: 20 yr old alpha gen II transom rebuild or buy new

My mistake, I guess the early Gen II drives do have bolts in the bottom. From 96 up, they used studs.
Personally, I would just replace the defective parts and a new rope seal around the perimeter of the drive.
The reason the bottom bolts broke is due to corrosion caused by water, water also causes rot in the transom.

Re: 20 yr old alpha gen II transom rebuild or buy new

Thanks Don.

I guess the big question is where did the water come in...obviously mercruiser thought it was a better design to eliminate the leak possibility around the bolt holes and go to all studs(the bolt holes are inside the transom seal perimeter which is my concern). My other possibilities are the seals underneath the trim anode, u-joint bellows, or shift bellows. Have I missed any area to definitely inspect and repair? This transom assembly is really a weird bolt setup. I have 4 studs, 2 bolts that run from inside the boat and thread into the transom shield, and the 2 carriage bolts at the bottom going from outside in. No wonder merc changed the design. Also I was able to find bolts for the lower 2, but they have the screw on anode acorn. Would these be OK to use? Can I use an exhaust tube instead of bellows? I've heard the exhaust bellows can be a big pain to change.

Re: 20 yr old alpha gen II transom rebuild or buy new

Why did the transom go bad? Simple, boat manufacturers do not take the time to seal any holes made in the transom. The cut out for the O/D and all bolt holes ideally should have some type of sealant coating the exposed wood inside the hole such that a flooded, or even partially flooded bilge will not allow the transom wood to get wet.

It would not take much effort or material (sealant, epoxy, anything) to coat those surfaces before bolting the transom plate into position.

Re: 20 yr old alpha gen II transom rebuild or buy new

and the 2 carriage bolts at the bottom going from outside in. No wonder merc changed the design. Also I was able to find bolts for the lower 2, but they have the screw on anode acorn.

Click to expand...

Ayuh,.... I'd guess somebody's been there before you...
Mercruiser has Never used carriage bolts, but always the anode bolts you describe...

Usually, it's rotten wood in the transom that starts the process that leads to where yer at now...