1991 Alumacraft Saggy Transom

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  #1  
Old 01-13-10, 02:06 PM
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1991 Alumacraft Saggy Transom

My '91 Alumacraft Competitor 185CS (18.5' Aluminum Walleye boat) appears to have a transom rot/sag issue (I think it was sank or sat full of water and dropped off the trailer prior to my ownership - naive boat buyer) that I need (or feel the need) to get repaired. From what I can tell, the Transom consists of an inner skin, 3 layers of 3/4" plywood and an outer skin. The outer skin is dimpled from the bracket that holds the engine onto the transom and I believe it is going to start leaking within the next season. The problem I have in doing this myself is the rivets. I am pretty sure I could drill all of the rivets out and get it taken apart but getting it back together (rivets) is my issue. I'm trying to track down a new outer skin and I can get marine plywood very easily but is it possible for a normal guy (mechanically inclined and learns easily) to do this job on a boat this size?

Sorry for the long post.. I wanted to get as much detail of the problem as I could to get the best possible response. I'm located in Minnesota and Camping and Fishing is a passion of mine but without a boat, I'm sunk. Any help would be appreciated!

Tim
 
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Old 01-14-10, 02:19 PM
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Slow board, or did everyone get rid of their boats?
 
  #3  
Old 01-14-10, 07:02 PM
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Everybody's ice fishing!

Welcome from another Minnesotan! And a free bump!

Sadly, I have no help for you since I know nothing about working on a boat but surly the must be a DIY way to fix it.

Maybe google "repairing a boat transom" Good Luck!
 
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Old 01-14-10, 07:41 PM
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Originally Posted by Tolyn Ironhand View Post
Everybody's ice fishing!

Welcome from another Minnesotan! And a free bump!

Sadly, I have no help for you since I know nothing about working on a boat but surly the must be a DIY way to fix it.

Maybe google "repairing a boat transom" Good Luck!
Yeah, I imagine so.. the weather is shaping up - hopefully this warm snap will trigger a better bite.. I had 17 crappies and a 29" pike two weeks ago in Chisago Co.

I've tried googling it bit it didn't come out as great as I had planned. Most of the links I got were related to small tiller boats or big fiberglass cabin cruiser type boats.. I just need a pro to weigh in on the subject.. The dealer I took the boat to for an estimate told me about $1900 to replace the transom. (engine r&r, new skin, new plywood, new fasteners)

Tim
 
  #5  
Old 01-15-10, 04:52 PM
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Sorry I haven't been around the computer for a bit.

You should be able to get ant aluminum parts you need from alumacraft. I'm not sure how they are built but we had a lund transom done last year. The lund has a cap on the transom and it looked like they took it off and just peeled the corners up on the gunnel and took it out that way.
As far as the rivets they are fairly easy. On the outside use the kind that you hit with a hammer and peen them over rather than the style that you use a rivet gun as those are hollow. Fill the hole with 3m 5200 sealant on all the outside holes.

Before you install new wood coat all the wood with some polyester fiberglass resin then a coat of oil based paint. This will keep water from rotting it again.

I haven't done a aluminum transom but have done a couple fiberglass ones.
 
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Old 01-19-10, 05:44 AM
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Originally Posted by samuari View Post
Sorry I haven't been around the computer for a bit.

You should be able to get ant aluminum parts you need from alumacraft. I'm not sure how they are built but we had a lund transom done last year. The lund has a cap on the transom and it looked like they took it off and just peeled the corners up on the gunnel and took it out that way.
As far as the rivets they are fairly easy. On the outside use the kind that you hit with a hammer and peen them over rather than the style that you use a rivet gun as those are hollow. Fill the hole with 3m 5200 sealant on all the outside holes.

Before you install new wood coat all the wood with some polyester fiberglass resin then a coat of oil based paint. This will keep water from rotting it again.

I haven't done a aluminum transom but have done a couple fiberglass ones.
I called my local Alumacraft dealer and in dealing with Alumacraft, they told me that they do not have a template for the transom skin (its damaged) and I'd have to take the existing one off and take it to a metal shop to have it made. I have access to the rivet tools and enough mechanical know-how to do the job.. now its just getting the skin made.. I was hoping that I could get the skin from Alumacraft and do the job in a weekend, but evidently this is gonna turn into a monstrosity.. Anyone have any ideas where I might find a skin w/o having to have it made in a shop?
 
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Old 01-19-10, 05:21 PM
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At this point you should just buy a piece of sheet metal and beat it into submission.

The rivets are easy compared to what you're about to do.

If I were you I would save the few hundred bucks (and countless hours of your time) and apply it to finding a different boat.
 
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Old 01-19-10, 06:26 PM
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If you take some good measurements I'm sure a tool shop can cut/bend you a piece of aluminum with out too much trouble.

My FiL just ordered me 450lbs of 1/4" plate steel that is flame cut (cut with a CNC torch). Total bill was $360. I think shops are looking for work too. Call around. I know a good one in Rogers, MN
 
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Old 01-20-10, 05:36 PM
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Originally Posted by Rick Johnston View Post
At this point you should just buy a piece of sheet metal and beat it into submission.

The rivets are easy compared to what you're about to do.

If I were you I would save the few hundred bucks (and countless hours of your time) and apply it to finding a different boat.
I'm not really in the position to go find another boat. I just replaced the entire plywood floor, new carpeting in the whole boat and put a new Gearcase/lower unit on it not to mention I haven't got several thousands of dollars laying around.. At this point, a few hundred bucks and some of my time is far more affordable. Thanks for the suggestion though.
 
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Old 01-20-10, 05:41 PM
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Originally Posted by Tolyn Ironhand View Post
If you take some good measurements I'm sure a tool shop can cut/bend you a piece of aluminum with out too much trouble.

My FiL just ordered me 450lbs of 1/4" plate steel that is flame cut (cut with a CNC torch). Total bill was $360. I think shops are looking for work too. Call around. I know a good one in Rogers, MN
Well, it seems that I will have to remove my old skin, bring it in to a shop and have them cut/bend a new one. From what I've been told, the aluminum they use for boats is a stronger alloy than typical sheet aluminum.. would you or anyone else happen to know if there's any truth to this?
 
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Old 01-20-10, 07:01 PM
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I will ask some people in the metal working trade and get back to you.
 
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Old 01-21-10, 06:00 PM
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I would still try and contact Alumicraft. I know we get gunnels from Lund for boats older than yours. They might sell the aluminum if nothing else.

I haven't herd what aluminum boats are made from.
 
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Old 01-24-10, 07:24 PM
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Originally Posted by Tolyn Ironhand View Post
I will ask some people in the metal working trade and get back to you.
Thank you, kind sir! Worst case scenario, I can re-use my existing skin (since its got some of its original paint left) if needed - I'd just fill in the holes from previous transducer installations and such with epoxy or something of that nature and just replace the plywood. I will have to wait to see what the cost is going to be to replace it (and paint it...).
 
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Old 01-24-10, 07:27 PM
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Originally Posted by samuari View Post
I would still try and contact Alumicraft. I know we get gunnels from Lund for boats older than yours. They might sell the aluminum if nothing else.

I haven't herd what aluminum boats are made from.
I already talked to them. They do not have ANY spec sheets or drawings for my boat. They told me "19 years ago our plans weren't computerized as they are now and they no longer have any of the drawings or specs for this age of boat". They are the ones that told me I'd have to have a new skin made using the old one as a template.
 
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Old 01-24-10, 07:37 PM
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Talked to my "guy" and the only thing he could think of is they use a more bendable aluminum such as 5052 or 5086 in order to be able to make the bends you would need for the hull. A "standard" aluminum would be a 6061. I have no idea what the numbers mean but he said that if you try to make a 90 degree bend with 6061 is would just crack rather then bend.

Hope this helps.
 
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Old 01-26-10, 03:25 PM
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Originally Posted by Tolyn Ironhand View Post
Talked to my "guy" and the only thing he could think of is they use a more bendable aluminum such as 5052 or 5086 in order to be able to make the bends you would need for the hull. A "standard" aluminum would be a 6061. I have no idea what the numbers mean but he said that if you try to make a 90 degree bend with 6061 is would just crack rather then bend.

Hope this helps.
That is a good thing to know - thanks a million for the info and looking into this for me. I'm not quite sure what I'm going to do just yet, but I'll take some measurements and call around and see what the going rate to make it is going to be..

Thanks again!
-Tim
 
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Old 04-02-10, 12:49 PM
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Well, I am undertaking the task of replacing the plywood transom in my boat - Over the winter the engine seemed to be sagging a little further. I have the rub rail trim removed as well as the aluminum trim on the inside of the gunnels. These are going to be recarpeted, so for ease of recarpeting and riveting the transom, I'm going to remove the gunnels from the boat. From what I've read, The best way to remove an outboard is using a lift eye on the Flywheel and engine hoist. Is this still the tried and true method or is there a better way? I have the hardware to make a lift eye on the flywheel but figured I'd ask before I tried it. The engine is a 1994 Johnson 120 J120TLARK. What does this engine weigh, roughly? I was going to lay it down on a couple of pallets after removal. Am I on the right path to getting this beast off?
 
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Old 04-02-10, 05:07 PM
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Sounds like you're making good progress.

I use a steering wheel puller and 3 bolts into the flywheel and a cherry picker, I have tried to use a comeallong but it's a pain. The hoist is a lot easier to move around, and a pallet works good but if your close to a dealer we give new motor crates away so the motor will not be laying on its side.
 
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Old 04-03-10, 04:48 AM
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It's tough to find exact weights, but if you plan for 400 pounds you'll be safe.
 
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Old 04-03-10, 03:21 PM
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Originally Posted by samuari View Post
Sounds like you're making good progress.

I use a steering wheel puller and 3 bolts into the flywheel and a cherry picker, I have tried to use a comeallong but it's a pain. The hoist is a lot easier to move around, and a pallet works good but if your close to a dealer we give new motor crates away so the motor will not be laying on its side.
I have a harmonic balancer puller which lines up with the holes perfectly and I have a 12v powered engine hoist that will lift it with ease. Space being limited with the boat in the garage, I am going to lay it down on a 2" styrofoam sheet with 1/2" plywood on top. It will only be off the boat for about a week so I'm not real worried about it being laid down. My biggest concern is the rivet tools. I have an air hammer but am having a hard time finding the riveting bits for the air hammer locally. The rivets are 3/16" and all I need is the bit to install them - I was hoping to find one locally so I didnt have to pay shipping (which is probably more than the bit itself). anyone have any suggestions? I live in the Mpls/St. Paul area in Minnesota.
 
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