i/o to o/b conversions?

[low277]

I have just came into possession of a 22ft Holiday that has/had a omc stringer in it. I have read a lot of threads here over last year or two and I think that I would like to try convert it to a outboard on a offshore bracket. I have read a thread by poster "Weldzila" who has built his own bracket. I dont think I have the skills or equipment to do that, I will have to buy a brecket.

Does anyone have any links to other conversions? Looking for info on transom reinforcement, adding knees etc.

 

[Bob_VT]

Re: i/o to o/b conversions?

It could prove to be almost the same price to find a donor boat with a volvo or mercruiser outdrive.......

You could rebuild the transom and ad a splashwell to make it into an outboard too...... regardless you have your work cut out for you.

Do you have an outboard motor on hand? There are allot of nickle and dime expenses related to a bracket conversion.

 

[jasoutside]

Re: i/o to o/b conversions?

Certainly lots of pros and cons both ways!

You can check the first couple of pages of my Islander thread. The guys and I really kinda weighed out the OB vs. OB on a Bracket vs. IO debate a bunch. Even though I went the IO route you may find the info of value.

You'll also want to check this one...

http://forums.iboats.com/boat-resto...kes-1976-22-starcraft-islander-551054-17.html

All the best:joyous:

 

[bob johnson]

Re: i/o to o/b conversions?

I am on the fence as well with my 22 ft starcraft islander. Since i want to use my boat periodically in the dead of winter, via of trailering to and from the water each trip.... I find myself handicapped with the I/O set up.

it certainly seems more expensive to rebuild an outboard than an inboard. But an outboard is way more simplified...
plus i dont see the need for a spalsh well... the back of an I/O boat is huge!!! the Gil bracket will hold the motor and you can mount it on the back of the huge I/O transom.... you just have to incorporate a fake transom angle fo the bracket so it holds the outboard at the proper angle. the full height of the transom works for the boat in its orginal form, why wouldnt it work for holding water back on an outboard?

plus it seems you would have quite a bit more room inside the boat, plus you can raise the motor so the lower unit clears just more than an Outdrive would.

the downside is buying or making the outboardbracket. and installing it correctly. then you would have to reinforce the trasnom with supports connected to the floor for strength. it would have to be STRONGER than a regular outboard transom to boot!! because of the leverage.

if it were me, id get a very long legged motor and mount as high as possible on the transom, and then keep the set back as short as possible. So you can easily reach the motoer from inside the boat... and lower the moment arm and forces the set back motor creates

bob

 

[low277]

Re: i/o to o/b conversions?

I like the thought of the extra room inside if I remove the dog house, I have never been on a boat with a gill / offshore bracket although I have seen numerous pictures of fiberglass boats that have been converted. I also have never owned a boat with a io in it, I have always owned outboard powered boats.

It appears that the going rate for a new outboard bracket is anywhere from 500 to 1500 dollars depending on whether it is a small single pod or a larger floatation type with say 30 set back and 7 foot width.

Lots of things to consider, I don't mind spending the money on a bracket if I can find a nice used 150hp outboard to mate it to. I have a Lund Tyee 4.9 that I am currently using so I can spend some time looking for parts and cleaning up the boat.

 

[WeldZilla]

Re: i/o to o/b conversions?

I believe the bracket is a great answer for many. But you must use an outboard with a 25inch shaft. You need that length of shaft to keep your engine up out of the water at low speeds this allows you to tilt your engine completely out of the water which is nice if your mooring up for awhile especially in salt water as I do every year. The extra room in the boat is fantastic. The net loss of weight of 238 pounds was great. There is not one thing that was not improved with my conversion. It is very nice to hit the water on a cold winter day knowing that to re-winterize the outboard you need to merely lower it all the way down when trailered and sitting in the driveway. I am going to shoot some more video of my 22ft. Sylvan out doing maneuvers to showe just how well it does with the outboard. I will be around here again if anyone needs some help .

WZ

 

[low277]

Re: i/o to o/b conversions?

Thanks Weldzilla, I have read your thread and am really impressed. I don't think my metal fabricating skills are anywhere near what your yours are so I am leaning heavily to buy a bracket. For now I am waiting for the weather to change and the snow to melt, snow should start to melt in a few weeks. The local news is starting to talk about the possible flooding of the Red River.

 

[Sc25175]

Re: i/o to o/b conversions?

Iow277, where in MN are you. I live down by the twin cities.

 

[WeldZilla]

Re: i/o to o/b conversions?

Well since your weather is still more wintery than spring like this is the time to get it all planned out. And have everything figured out in your mind just how you are going to proceed. you can price out Stainless steel fasteners. I recommend 1/2 in. bolts use a little never seize on the bolts Try to use 2 different grades of stainless as it helps prevent galling. Just the act of running a stainless nut onto a stainless bolt can cause it to gall and seize. you must use never seize and run the nut up slowly.
There are a lot of little things you can do to get ready. I recommend a piece of 6 inch aluminum channel to use as the backer on the inside of the transom

WZ

 

[low277]

Re: i/o to o/b conversions?

Stevesmith, I am in Roseau county on the Minnesota / Manitoba border. Weldzilla, by 2 different grades of stainless steel do you mean the bolt and the nut should be different grades? Grade 8 bolt with a grade 5 nut.....

 

[WeldZilla]

Re: i/o to o/b conversions?

low277 you are thinking of hardened steel fasteners. When I bolted up my transom bracket I use 1/2 stainless bolts that were made from 18-8 stainless as were the washers. the nuts were made from 316 stainless. You can use both 18-8 nuts and bolts but you must use never seize and you must run them up slowly. even when you run different types of stainless a little never seize should be used.

WZ

 

[low277]

Re: i/o to o/b conversions?

Weldziilla, I did some studying last night and I now have a better understanding of the stainless steel types of bolts and hardware as well as more insight as to what galling is.

I do have a question.... from what I have read on this forum I believe that I should use 5052 aluminum to fill the hole from the omc outdrive and for any plate that I add over the rear of the transom, the channel that is used on the inside of the transom, can this be of 6061 alloy?

I also see two different types of 6061, one is listed as (AL STD) the other is (AL ASSOC) the AL STD seems to be considerably cheaper. Is one preferred over the other?

Thanks in advance.

 

[WeldZilla]

Re: i/o to o/b conversions?

You can use the 6061 but I myself used all 5052. Thats the stuff aluminum boat dreams are made of. For the welding part of the operation get yourself some .035 5356 aluminum wire and use pure argon for your cover gas and go right after it.

 

[bob johnson]

Re: i/o to o/b conversions?

I just pulled the motor and transom assymbly out of my islander.. and am moving along with my project. the inside is getted and i am about to cut the cuddy off. I am going with an open layout with a small side console. I want to install an outboard now, and have been looking for a 25 " motor in 150 or 175 made by johnson or evinrude. It has to be a 60 degree V looper, as i already have a parts motor in a 1994 Evinrude 150 hp Intruder, ( with zero comp in the # 1 hole).. i am having a real hard time finding 25 leg motors at a decent price around here(northeast). and i looked up all the 1970-1982 litrature for the 21 ft boats by starcraft. They all had 21 " transoms if they came with an outboard....so why d you guys seems to insist that the outboard have a 25" leg?? sure it will be higher mounted...but a 21" leg motor will act pretty much like a factory outboard, wont it?,.... I am going to have to start looking into making the bracket soon.....and i want to incorporate as much bouyancy in it as possible while having my outboard mounted at the right hieght...bob

 

[low277]

Re: i/o to o/b conversions?

Its been a slow start to spring here, the snow is starting to melt, maybe a couple of more weeks. I have been looking for used 150hp outboards with 25 inch shaft, they are out there, I even found a 150hp Force with controls about 30 miles from my home. I have yet to go look at it.

 

[ezmobee]

Re: i/o to o/b conversions?

I wouldn't buy a Force unless it was super cheap.

 

[low277]

Re: i/o to o/b conversions?

From what I have read Force was a Chrysler product until the early 1990s and then Mercury took it over, does that sound right? The model in the above post is a 1998 if it makes any difference. Or just stay away period?

 

[barato2]

Re: i/o to o/b conversions?

try this: price all your common replacement parts for it and then decide. the engineering isn't hideous, just the parts availability and cost will be issues. all else being equal, i'd only pay 50-70% of what i'd pay for an equiv OMC/Merc/Japanese motor

 

[RogersJetboat454]

Re: i/o to o/b conversions?

From what I have read Force was a Chrysler product until the early 1990s and then Mercury took it over, does that sound right? The model in the above post is a 1998 if it makes any difference. Or just stay away period?

FWIW, Chrysler produced OB's were badged as Chrysler OB's until the early 80's when bankruptcy forced them to divest their assets. Chrysler's marine engine division was purchased by US Marine, and they sold the engines under the Force name. Mercury/Brunswick acquired US Marine in the early 90's, but kept the Force name.

The basics of those engines didn't change much, no matter who's name was on the cowl. While they were fine motors, and reasonably reliable back in their day, the design started to get pretty long in the tooth by the 90's, and they were more or less sold as "low rent" engines to be packaged with "low rent" boats.

 

[ezmobee]

Re: i/o to o/b conversions?

From what I have read Force was a Chrysler product until the early 1990s and then Mercury took it over, does that sound right? The model in the above post is a 1998 if it makes any difference. Or just stay away period?

That's probably the newest Force possible but it's still a Force despite Merc's ownership and they have not continues supporting them with parts. I'm not saying at all that they're junk motors but the parts support sure ain't gonna get any better. Just don't pay near what you'd pay for a supported brand.