Replacing 165 drive with Alpha drive

[NZ-Kevin]

My boat has a 165 drive, which is now in quite a poor state. Spares for this are not too common, and it would be difficult and expensive to rebuild. As an alternative I'm considering replacing it with a secondhand Alpha drive. This will make spares easier if I ever need to do more work, and cure all the current issues. The original straight 6 engine was replaced with a V6 about 12 years ago. What are the problems or issues I'm likely to face if I do this swap? Will I need a new bell housing to match the engine to the drive? Will the exhaust matcht up? Is it difficult to convert an Alpha drive from hydraulic steering (there isn't hydraulic steering on the boat, but most Alpha drives have hydraulis steering).

Any advice would be very helpful -especially if someone has already dopne this.

 

[achris]

Re: Replacing 165 drive with Alpha drive

My boat has a 165 drive,

No, your boat has an MC-1 drive. The only thing '165' on that drive is the label that says, 165...

which is now in quite a poor state. Spares for this are not too common, and it would be difficult and expensive to rebuild. As an alternative I'm considering replacing it with a secondhand Alpha drive.

Good idea

This will make spares easier if I ever need to do more work, and cure all the current issues. The original straight 6 engine was replaced with a V6 about 12 years ago.

So the 'new' engine is still running the 1.65:1 ratio...

What are the problems or issues I'm likely to face if I do this swap?

None

Will I need a new bell housing to match the engine to the drive?

No

Will the exhaust matcht up?

Yes

Is it difficult to convert an Alpha drive from hydraulic steering (there isn't hydraulic steering on the boat, but most Alpha drives have hydraulis steering).

Says who?!?!? Most Mercruiser drives have mechanical steering cables which, when properly maintained, are superior to some botched up, poxy, leak prone, 'notchy' hydraulic steering....

Unless you're talking about 'power steering'. Completely different animal. The power steering is associated with the transom housing, not the drive.

Any advice would be very helpful -especially if someone has already dopne this.

Hope I have given you enough advise to make the job simple. Basically it's a straight 'bolt off, bolt on' job. The Alpha One drive is a direct replacement for an MC-1. Shouldn't take you any longer than about 30 minutes to do the entire job. Just be sure about the ratio of the 'new' drive you're putting on. It needs to be either 1.65:1 or 1.84:1....

Chris.........

 

[NZ-Kevin]

Re: Replacing 165 drive with Alpha drive

I was planning to swap the whole unit, transom plate and everything. Are you saying I can bolt an alpha drive straight into the MC-1 housing? But the reason for changing everything is that the gimbal ring is quite worn, with a lot of play in the hinge pins and I can't get it off as the stainless pins that secure the hinge pins are seized in place. This all has to come off as the gimbal bearing is rusted in place and I need to get to it to get it out. Water has been through the top seal from the gearbox and into the gimbal bearing, so it's likely to be a mess when I get in there anyway.

Yes, the current engine is running the 1:1.65 ratio, which is what I intend to replace it with. it is a carburetor V6, so not much more powerful than the original straight 6, just newer and a better shape for the boat.

Yes, I meant power steering -which the alpha drives I have seen for sale all have. I presume uit's not too difficult to remove that?

 

[achris]

Re: Replacing 165 drive with Alpha drive

Sorry, when someone says 'drive' we assume they are referring to the section of the power package known as the 'drive'. If you are replacing the transom assembly AND the drive, that is a completely different story. It will depend on the year of the original assembly, and if you are talking about the SS 'nails' in the hing pins, then it's a very early MC-1. The keyhole cutout will need to be widened slightly in 2 places. Also depending on which model of Alpha you get you may need to change the flywheel cover on the engine.

The removal of the power steering unit and fitting of a non-power steering 'steering tube' is very easy...

Yes, the current engine is running the 1:1.65 ratio, which is what I intend to replace it with. it is a carburetor V6, so not much more powerful than the original straight 6, just newer and a better shape for the boat.

Are you kidding me!!!! You've gone from 165 crankshaft hp (when new and blueprinted) to 175 (2bbl carb, 205 for a 4bbl) Propshaft hp....


Chris........

 

[Bondo]

Re: Replacing 165 drive with Alpha drive

Sorry, when someone says 'drive' we assume they are referring to the section of the power package known as the 'drive'. If you are replacing the transom assembly AND the drive, that is a completely different story. It will depend on the year of the original assembly, and if you are talking about the SS 'nails' in the hing pins, then it's a very early MC-1. The keyhole cutout will need to be widened slightly in 2 places. Also depending on which model of Alpha you get you may need to change the flywheel cover on the engine.

The removal of the power steering unit and fitting of a non-power steering 'steering tube' is very easy...



Are you kidding me!!!! You've gone from 165 crankshaft hp (when new and blueprinted) to 175 (2bbl carb, 205 for a 4bbl) Propshaft hp....


Chris........

Hi Chris,... I'm runnin' the 1.65:1 ratio with my 4.3l, 4bbl....

What are you runnin' with yer Mpi,..??

Kevin,... Yer swap should go pretty easily,...
As Chris said, maybe abit of trimmin', 'n possibly an other drilled hole or 2.....

You'll probably need the matchin' y-pipe for the new transom assembly...
Get the new trim pump, 'n trash all the extra plumbin' stuff on yer 165 too...
The P/S is also a pretty easy self explanatory kinda thing...

Are ya goin' Alpha 1, or Gen.II,..??

 

[NZ-Kevin]

Re: Replacing 165 drive with Alpha drive

probably an Alpha1, just depends what I find that I can afford.

Would the later MC-1 gimbal ring fit into my earlier transom? There is one of those for sale, with the right gear ratio, which might be a simpler fix. It has everything so I coud just use from the transom plate back. Quicker and cheaper the better, but definately no bodge jobs.

 

[achris]

Re: Replacing 165 drive with Alpha drive

Kevin - Later model gimbal ring will not fit.

Bond-o. My current V6 (MPI) runs a 1.62:1 drive, my previous ran 1.84:1

 

[NZ-Kevin]

Re: Replacing 165 drive with Alpha drive

There could be some good news with the gimbal ring. today I managed to get the first hinge pin out. I drilled it from the end, through the stainless pin holding it in place. Once I drilled it to 9/16" I was able to get a small grinder in to remove the ende of the stainless pins and pull the remainder of the hinge pin out. If I can do this on the other side I can then get the gimbal ring into the workshop to drill out the rest of the stainless steel pins and enlarge the hinge pin hole then machine up some new, slightly oversized, hinge pins. I'm going to hold them in with stainless steel split pins this time -so I have a chance of getting them out again.

Anyone know what these pins were made of, it wasn't hard to drill and wasn't stainless steel. Just seemed to be mild steel. I might use silver steel (drill rod in US?) if I can get a suitable size -less machining and a great surface finish.

 

[AviatorJim]

Re: Replacing 165 drive with Alpha drive

Just to add my .02. I'm having to replace my transom ***/gimbal due to corrosion, and the ring breaking. I'm putting on the Alpha transome assy, but staying with the 165 engine and MR drive until they fail. The engine comes out this week, and then I'll see how the swap goes. I have been planning on using the existing inner transom plate if it is compatible, but I'll change it if I need to.

Let me know if you have a 165 engine core laying in your back yard. I don't have the option of changing engines.

--Jim

 

[NZ-Kevin]

Re: Replacing 165 drive with Alpha drive

Good luck Jim, hope the swap goes well. It seems as I have the early drive it would mean mods to the transom to get an Alpha to fit, which is more work than I'd like to do. trying to fix the current parts now, mostly problems with the gimbal ring -but we'll see what it all looks like when the bell housing and gimbal ring are off. I don't have any parts, the new engine had been fitted before I got the boat.

 

[cr2k]

Re: Replacing 165 drive with Alpha drive

I usually just bend the small ends (hinge pins/nails) and they pull right out in about 2 min.

 

[NZ-Kevin]

Re: Replacing 165 drive with Alpha drive

I usually just bend the small ends (hinge pins/nails) and they pull right out in about 2 min.

Either your incredibly lucky, or I've been unfortunate. These stainless nails that hold the hinge pins in are solid. Even after drilling the middle out of one I'm going to have to drill the two ends out of the gimbal ring because they still won't move. I can see why this design was soon dropped, pity the newer type gimbal ring won't fit or I'd swap it over.