A little crazy?

Corrosion, Paint, Through Hulls, etc.
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TinLizzy
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Location: Lake Superior-Michigan's U.P.

A little crazy?

Post by TinLizzy »

This past spring I sold my 1975 28 express and bought a 1990 32 express with twin 360's. Overall I love the boat. But one of the main reasons I upgraded was to see if I could transform a 32 inboard into a 32 Sterndrive. I know most people think that I am crazy, but hear me out.
I boat on Lake Superior, mainly traveling to Isle Royale National Park, which is 60 miles across open Lake Superior. The gas is usually around $5 gallon out there most years. I'm guessing its going to get much worse with our current atmosphere. My old 28 would use roughly 60-65 gallons traveling 75ish miles from gas dock to gas dock. Optimistically cruising at 29 to 30 mph if the weather allowed after I installed a pair of 350 Chevy's, and ran them at 3100 rpm. The new to me 32 uses about 85- 90 gallons going 25-26 mph at 3100 rpm.
My main reason we go out there is to fish. My preferred method is casting in shallow water when the fish are there. The Island is very rocky, with the bottom going from 250-300 feet of water to ankle deep in the length of a boat in many places. I try to position the boat so it is being blown out to deeper water as we pull up to a spot and start drifting. The problem is that the wind will switch quite rapidly and all of the sudden we are headed into dangerously shallow water.
I am a marine mechanic by trade. So I concocted the idea of buying a donor boat with a pair of 454 Mercruiser engines with Bravo 1 outdrives. I bought the boat, pulled the engines, outdrives, transom assemblies and all other parts needed for the swap. Then sold the hull.
I pulled the 360's out of the 32, they ran great, but I'm lookng for more horsepower. Removed the water heater, waste tank, exhaust, shafts, rudders, etc. The only thing left to take out is the struts, fuel tank, and flooring.
I have a buddy that is an aluminum welder. We are going to cut out two sections of the rounded transom. Make new flat panels for the transom assemblies to bolt to and weld them in. Drop the engines onto the rear mounts, and the see where the front mounts will need to be fabricated along with new sub stringers and more gusseting on the transom.
The weight transfer to aft is a concern, but after talking with a couple engineers I believe it won't be too detrimental, but that is not a sure thing.
My ultimate goal is to have a 32 express that will cruise at 32 to 34 mph at 3000 to 3200 rpm. And have the ability to trim up the outdrives when fishing in shallow water. Everything I have read about boats that were optioned with sterndrives and inboards, the sterndrives were hands down to performance winner. Better speed and better fuel economy at any given rpm. After researching fuel flow rates for 454's with Bravo drives on boats that weigh around 12,000 lbs. I believe that I will be burning around 25 to 30 gph total for both engines. Which will put my fuel usage back to were it was with my 28 ft.
The exhaust noise is also one of my pet peeves. I start to get a headache listening to that above water exhaust for hours on end. Converting to sterndrive makes the exhaust come out through the prop, which makes it quieter.
One of my main problem right now, is that I live in the U.P. of Michigan, and it has already started to freeze at night, we regularly get over 250 inches of snow most winters, with the record being 378 inches in 1978. The storage building I keep my boat in does not have heat or electricity. So that makes it hard to get the fabricating done. I had worked out a deal with a local trucking repair shop that had room inside that I could do the work. But the garage doors are right at 12' wide and I measured 12'2" on the widest part of the beam as well as I could. So that won't work. My next option is to open the main garage door at my work, back to boat in as much as I can and tarp around the opening to keep most of the heat in as we work on it.
We are still working out some of the fine details before we start cutting. My plan is to always be able to put the boat back together as an inboard if this doesn't work for some reason. The only thing getting in the way of that is that the rudder posts will have to be cut down so the new engines will be able to fit where they need to.
I have put a lot of thought into this for quite a few years, and decided that if I don't do it now, I never will. So here we go! Thoughts? Suggestions?
Rodney
1975 28 Express-Twin 350 Chevy's, SOLD
1990 32 Express-Twin 360's
Portage Canal Waterway-Upper Peninsula,Lake Superior
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Busia
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Re: A little crazy?

Post by Busia »

First, do you have the hull on a trailer? If not, get one. It will pay for itself. Then with a forklift or just hydraulic jacks, heel the boat over to one side so it is only 11' 6 inches wide. ( I put timbers across my trailer front and back. Set the hull on the timbers and laid it on one side then the other to weld on a new bottom) Then it will fit through the 12' door. Otherwise, I would keep it in the storage building and just put in a temp. wood stove to heat it while you are there working. Or back it in at work and tarp off the opening. Mostly what is most convenient. If you have the hull on a trailer at your work, you could put it in when you need to and pull it out and close the door when you want to go home.
Now the changes. You will have a vessel that is very stern-heavy. Plan on water and gas as far forward as possible, and plan on big trim tabs even if you trim the outdrives. On my 32' I have 350 Chev (Crusaders) and find I have more power than I need. I think your hull will be so light that you won't be able to handle all the power available. Good luck with the project, hope it works out well for you.--Ed
( you ever think about just fishing somewhere the water is deeper? and another note, I was born in Michigan, my Dad and Uncle used to sail on the Great lakes. I was young when we moved so I don't remember much from back there. Here is where I am now. My wife with a nice king salmon.)
Sherry @ 14K.jpg
Sherry @ 14K.jpg (17.48 KiB) Viewed 573 times
BUSIA
located in Ketchikan, Alaska. Gods country
32 foot Marinette express. (no fly bridge)
twin 350 Crusader (Chev 350) engines
1:1 Borg Warner velvet drive transmissions
Closed cooling (antifreeze in the engine)
Proud to be retired IBEW
Fastjeff
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Re: A little crazy?

Post by Fastjeff »

You're "crazy" alright, but I love your project! The boat will be very stern heavy but, with the tilt of the outdrives, you should be able to correct that. (If not, let me know: I have a fix that I used on my bow rider.)

A few things you already know: The torque of the outdrives is absorbed through the transom, like an outboard, so you'll need massive bracing tied into the keel (preferably) to prevent distortion. Just adding some thick Al plate to the transom would not be enough.

The weight of those 360s and their marine transmissions might be closer in weight to the 454s and Bravo drives than one would think. I'll bet within 100 pounds per side.

Are you planning on having the props counter rotate? I assume the donor boat was set up that way.

Jeff

PS: Wish I lived nearby. Love to help you with this.
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington
TinLizzy
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Joined: Mon Jan 19, 2015 11:07 pm
Location: Lake Superior-Michigan's U.P.

Re: A little crazy?

Post by TinLizzy »

Thanks guys. Yes, with Bravo drives they can be run in either direction without having to change the lower unit to a counter rotation like an Alpha. It is on its own trailer, but it is only a yard trailer that is not that great. I hope to remember to take pictures and will try to post the progress to let people see what I am up to.
Rodney
1975 28 Express-Twin 350 Chevy's, SOLD
1990 32 Express-Twin 360's
Portage Canal Waterway-Upper Peninsula,Lake Superior
javalin390
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Re: A little crazy?

Post by javalin390 »

Just a thought, have you ever contemplated outboards? I have seen a few M's that had the transoms modified for this conversion. Modern outboards are small and powerful and can be removed for service by just lifting them off. There is a lot of people that have done the conversion on glass boats as well.
Jim Elias
1974 37' SedanFlybridge
Twin 360 Chryslers.
Marblehead, Ohio
TinLizzy
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Posts: 146
Joined: Mon Jan 19, 2015 11:07 pm
Location: Lake Superior-Michigan's U.P.

Re: A little crazy?

Post by TinLizzy »

Thanks for the suggestion, but when all is said and done, I am looking at having well under $10k into the project. Besides not being able to find a pair of quality used 300 hp 4 stroke outboards. New ones run around $25-28K each. Throw in all the new rigging and new bracket that would need to be made or purchased, I would estimate that it would cost about $65 to 70k to do it. New four stroke outboards are definitely leaps and bounds better that the old 2 stroke outboards. But I just have never been a fan of them on big cruiser boats.
I pulled out the fuel tanks last week, and hope to pull the flooring up this week. It will be nice to have it all wide open below deck to work down there. I got a chance to clean the bilge a little bit where the old engines sat, but gave up pretty quick as my hands were feeling like little pop-sickles.
Question, I know I have seen it on here previously, but what are some of the better methods for removing that damn tar goo that they sprayed on the inside of the hull? I am think a heat gun and scraper?
Rodney
1975 28 Express-Twin 350 Chevy's, SOLD
1990 32 Express-Twin 360's
Portage Canal Waterway-Upper Peninsula,Lake Superior
Fastjeff
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Posts: 1415
Joined: Sat Jul 12, 2014 5:06 am
Location: Rock Halll, MD

Re: A little crazy?

Post by Fastjeff »

It can be loosened up with a solvent like lacquer thinner, but the resulting mess is even worse!

Hang in there.

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington
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