Advice needed-installing AQ131A and outdrive into a new dory

film842

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I could use some opinions on my plan, which is to remove my AQ131A motor and outdrive from my '87 Bayliner and install it into a 21' Pacific City dory that I am building.

There are no guides (that I know of) on how to make this installation and so I am assuming that it should not be terribly difficult to figure out? I am only a so so mechanic but usually get where I'm going after a bit of research and agony.

Would love to hear from anyone who has had experience with this or just has an opinion.

Any thoughts much appreciated.
 

Don S

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Re: Advice needed-installing AQ131A and outdrive into a new dory

What is a 21' Pacific City Dory? Pictures or plans?
 

film842

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Re: Advice needed-installing AQ131A and outdrive into a new dory

What is a 21' Pacific City Dory? Pictures or plans?

Ooops. Didn't think of that. I don't have postable plans with measurements, but a plan view can be found here:

LITTLE HUNK Line drawings

I will be building the "little hunk" with stronger ribs and heavier plywood and 3 feet longer (to 21').
 

Don S

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Re: Advice needed-installing AQ131A and outdrive into a new dory

The biggest problem you are going to have with that boat is the transom angle. Specs call for 10 to 15? angle, but in reality to keep the engine level in the boat you want 12 to 13?. The drawing is showing about a 29? angle for the transom. Ok for a Dory style boat, not ok for an outdrive.
 

film842

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Re: Advice needed-installing AQ131A and outdrive into a new dory

The biggest problem you are going to have with that boat is the transom angle. Specs call for 10 to 15? angle, but in reality to keep the engine level in the boat you want 12 to 13?. The drawing is showing about a 29? angle for the transom. Ok for a Dory style boat, not ok for an outdrive.

Interesting and a basic question that I will need to get an answer too. There are boats like this being used now and I need to make contact with those folks and see how they dealt with it.

Do you suppose that one would want to move the shift and steering components over to the dory as well? I guess I'm wondering if there is any reason that they could not be made to work.
 

Don S

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Re: Advice needed-installing AQ131A and outdrive into a new dory

The boat is designed for outboard motors in a box, not outdrives attached to the transom. The transom would also have to be 1-3/4 thick. It's what supports the transom shield, outdrive, and engine.
You are doing something the boat was never designed to do.
Your best bet would be to look for a boat plan that is designed for an outdrive.
 

Don S

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Re: Advice needed-installing AQ131A and outdrive into a new dory

These pictures will give you some idea what would happen with the engine when it's in a boat with a standard 12 or 13? transom, and what happens to the engine and drive when on a 29? transom. You wouldn't be able to trim the drive high enough to run it without ujoint damage, and your engine isn't going to like being at a 16? nose up angle.

Here is the engine at 12? normal mounting.
12.jpg

Here is what it would look like at 29?.
29.jpg
 

captmello

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Re: Advice needed-installing AQ131A and outdrive into a new dory

Those drawings are great Don.

Many I/O hulls, including mine have a center section of the transom to support the Transom shield, etc, and then the transom changes on the outside. In fact your aq131 may be supported completely by the transom, with no mounts on the hull/structure...

03-21-09_1236.jpg


Could the transom be built like this? With different angles in the middle and outside?
 

film842

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Re: Advice needed-installing AQ131A and outdrive into a new dory

These pictures will give you some idea what would happen with the engine when it's in a boat with a standard 12 or 13? transom, and what happens to the engine and drive when on a 29? transom. You wouldn't be able to trim the drive high enough to run it without ujoint damage, and your engine isn't going to like being at a 16? nose up angle.

Here is the engine at 12? normal mounting.
View attachment 177053

Here is what it would look like at 29?.
View attachment 177054

Thanks for the input. There are a number of these boats with inboard outboards being used and clearly I'm going to have to go have a look at them and see how they handled it. I suspect that the portion of the transom that holds the engine (Mine is supported by the transom only although front engine mounts could be fitted) is at a different angle than the rest of the transom, or they build the transom at the correct angle for the motor. I'll report back with what I find.
 

film842

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Re: Advice needed-installing AQ131A and outdrive into a new dory

CKdory12.jpgWest_Wind_2_2_.jpg

You can see by the transom photo how this was done. The motor/drive is mounted at the correct angle on a piece of transom which is then incorporated into a well and boat's full transom is then tilted to the correct angle. This boat was built for beach launching which I will not be doing.

The other photo is of another dory which is a terrific example of a Pacific City dory.
 

captmello

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Re: Advice needed-installing AQ131A and outdrive into a new dory

From your other thread,

For what it's worth, there seems to be more opinions against putting an I/O in one of these dorys as opposed to an outboard. However, others who have them say they work fine, the boat is well balanced, it can be worked on by most folks and as long as you are vigilant with maintenance and upkeep, it should be fine. So, we'll see.

While i'm certainly no expert, I do own an outboard and an I/O. This is more of an I/O v. Outboard argument, imo. Maintenance, service costs and requirements, and long range plans should be considered in your project.

What is your motivation to install the I/O? If it's just because you currently have one, that's not a good enough reason. The old Volvo drivetrain is just that, old and they need quite a bit of maintenance and upkeep, and parts aren't getting any cheaper...
Also the Volvo outdrive cutout in the transom is unique to the older stuff, so you're stuck with that cutout if the engine/outdrive need to be replaced in the future.

An outboard, while perhaps not in your possession, and perhaps having a larger upfront cost may be the more practical choice. Outboards require much less maintenance and are easily repowered with another outboard if needed without being limited to a certain brand or style.

You might be able to sell the I/O setup for enough money the buy a decent used outboard. You mentioned not being a great mechanic. So unless you're looking forward to honing your skills on the Volvo I/O, and there's nothing wrong with that, an outboard may be the answer. If you look forward to working on the I/O and tinkering with it, well than go ahead and install it. I would be happy to help with your mechanical questions should you have any.

Just my .02.
 

film842

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Re: Advice needed-installing AQ131A and outdrive into a new dory

From your other thread,



While i'm certainly no expert, I do own an outboard and an I/O. This is more of an I/O v. Outboard argument, imo. Maintenance, service costs and requirements, and long range plans should be considered in your project.

What is your motivation to install the I/O? If it's just because you currently have one, that's not a good enough reason. The old Volvo drivetrain is just that, old and they need quite a bit of maintenance and upkeep, and parts aren't getting any cheaper...
Also the Volvo outdrive cutout in the transom is unique to the older stuff, so you're stuck with that cutout if the engine/outdrive need to be replaced in the future.

An outboard, while perhaps not in your possession, and perhaps having a larger upfront cost may be the more practical choice. Outboards require much less maintenance and are easily repowered with another outboard if needed without being limited to a certain brand or style.

You might be able to sell the I/O setup for enough money the buy a decent used outboard. You mentioned not being a great mechanic. So unless you're looking forward to honing your skills on the Volvo I/O, and there's nothing wrong with that, an outboard may be the answer. If you look forward to working on the I/O and tinkering with it, well than go ahead and install it. I would be happy to help with your mechanical questions should you have any.

Just my .02.

Even as much as I'd like to use my I/O because I own it, your comments make a great deal of sense. I can't deny that installing the I/O will require a good bit of time and fiddling, perhaps more than I'm capable of. The simplicity of a good outboard is pretty compelling. It's a good motor and drive and I know there are people looking for them, so perhaps I'll just put it up for sale.

My ultimate aim is to have a good solid fishing and crabbing boat for bays and occasional ocean jaunts. And in order to feel safe doing that, I want to know the boat and power systems intimately. The old Bayliner that this motor and drive is coming out of has more little things wrong with it than I can name, any of which would stop it in it's tracks.

I appreciate your thoughts on this. Of course finding a good used outboard is probably another art I'll need to master.
 

captmello

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Re: Advice needed-installing AQ131A and outdrive into a new dory

Of course finding a good used outboard is probably another art I'll need to master.

Don't be afraid to post this question on Iboats, lots of good advice here!:)

FWIW, outboards are a completely different animal. If you go that way, be ready to pay to have it worked on. Not that is has to cost a lot, but I don't think they are as diy friendly as an I/O but again, that's my opinion.

Good Luck with your project!
 
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