I/O to Outboard: 22ft. Sylvan offshore from 3.0liter OMC to Suzuki DF140

[WeldZilla]

I bought my 1988 Sylvan 22ft. offshore in August 2010. I knew when I bought it that the OMC outdrive was short for this world but, the price was so right I bought the boat because I have wanted one of these for years!!
I figured to swap the omc for a Mercruiser. Then I was reading these forums and stumbled onto a few I/o to outboard conversion threads. That got me to thinking about it and I am afterall WeldZilla.... So I pulled and sold the 3.0liter engine and parted pretty much everything else. I have around $500 into aluminum and stainless steel bolts, washers and nuts. I welded out my bracket in a day.
I used my pullzall to remove old and help mount the new. The bracket works perfectly. I used a piece of 6 inch aluminum channel for the main upper supprt and a piece of 3 in aluminum angle for the lower support. I bought a Brandnew 2011 Suzuki DF140 which is very light and Quiet... This whole project was quick and simple.

WZ

 

[WeldZilla]

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

well after mounting the bracket it was time for the engine. I purchased my new suzuki from Sportcraft marina in portland Oregon.
They were great!! Then it was time to go!!

Here is a short you tube video also

http://www.youtube.com/watch?v=pur5ARQZjW0

That was loping along at 27mph at 4200rpm.

WZ

 

[boatnut74]

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

That's what I call a repower! Nice job!

 

[jasoutside]

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Holy cow! Look at that!

An IO to OB on a bracket conversion - often discussed, rarely seen! Awesome!

Looks like you did a bang up job there.

Very interesting

 

[Teamster]

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Nice work,..............

 

[greenbush future]

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Just curious about what that kind of new motor will cost, out the door? Nice job on the fab work too, looks like it belongs on that boat, bet it free's up a ton of room in the back too.

 

[ezmobee]

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Really really GREAT work! Thanks for sharing it.

 

[zopperman]

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

First successful conversion I've seen. I'd love to see an FG one

 

[WeldZilla]

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Well thanks to all who commented. Now to the Biq Question....

The Suzuki DF 140 was $10,680 installed that includes new steering system. I bought the zero feed back system. I can't decide whether that was good or bad... Time will tell.

I used 3 1/4 spools of .035 5356 aluminum wire.
I used about 1/20th of a role of .023 5356 aluminum wire welding the keyhole shut.

My welder is a Millermatic 200 its an older machine so I use an SGA100 control box so I can run my Spoolmate 3035 gun

The aluminum I used was 5052 plate which is marine grade. I use 3/8 at the front of the mount and also at the back for the engine to bolt to. The sides and top ( swim platform ) were made from 1/4 inch plate.

it was my first time using the small .023 wire and I loved it. I welded in the keyhole in virtually one quick nonstop pass. I cleaned it up and went over about 4 inches you will see in the pic.

I just could not see paying from $ 1250 + shipping all the way to $2250 + shipping. Aluminum don't cost that damn much....

The boat sits virtually the same in the water the ouboard is further back but was almost 280 lbs. less.

The boat is on plane at 12.7 mph before it was at 13.2. This is as near as I can figure using my depth finder speedo.

This project is not over I am going to build storage and fish boxes inside the boat using the aluminum backing plate as the foundation.
I will post that project up when I get to it.

Here are a few more pics... If anyone has questions fire away i will do my best to answer them...

I plan also a removable ladder for the swim platform. The swim plat form I built is 69 inches wide. The trolling backet was really a very simple add on.

I welded the piece back in the squarish hole after welding out the transom bracket . It is water tight.. You notice when I cut it out I did it with rounded corners. you should never weld square corners they will stress crack over time.

The boat is roomier than I dreamed!!! OK well I maybe dreamed about more room.... But I think you get it...

Again thanks for looking


WZ

 

[jasoutside]

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Thanks a bunch for the extra details! I was wondering about some of that stuff.

Other stuff I am wondering...

So hey, what did your top end speed come out at?

Can you describe your process of determining the mounting height? (I know that can be a tricky part of this conversion)

And, where abouts are you located? What kind of waters are you running in?

Cheers!

 

[WeldZilla]

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

My top speed is around 38mph.

OK well as to the height of my prop. Well this was kinda some seat of the pants. The Suzuki is a 25inch shaft. I did some dome gestimating that with the 29 inch offset that I would get about 3inches of swell back there

So I set the top of the mount at 28 inches. The boat shop asked me to cut that down to 27. I explained to them my reasoning but they asked me to anyway. When it was said and done it ended up 28 and 1/4 inches.

How was that for close!!! I also figured the height of the engine from the pivot point and knew my 29 inch offset would allow me to tilt the motor completely. You know I have not done this particular type of project before but I run a weld

shop for a dredging company where We repair steel work boats. Aluminum Survey and crew boats. I just do this stuff...... When I get home from work I head out to my shop.. I ciphered on this for a few weeks just staring at the boat from

inside and sitting behind the boat till the whole idea just came together. I cut the pieces and built it in a day once I knew what I wanted.

As to the waters I run in. Well I live in Vancouver Washington. Just about 20 minutes from the boat ramp in Camas that pus me on the lower Columbia River. I salmon ,steelhead, walleye, bass and of course sturgeon fish.

I also own a place on the Longbeach penninsula in Southwest Washington. I put my boat into Willipa bay and drop my crab pots then run over to Long Island where we all pile out into the mud and get Steamer clams!!

I also put in at Ilwaco Washington and fish Buoy 10 and crab in Baker Bay off the north Jetty. The wave action of Columbia River and Pacific Ocean gets pretty Strong. I have had people get sea sick..

Myself I just love it. No better place than right here for fishing and and getting seafood. I need to install radar and gps with C-maps next.... I love boats cuz they just so willingly take my money!! But they give me peace of mind in return

and I'll take that deal anyday...

You know someone commented about people talking about this but never really doing it. Well I am one of those guys that just tears in, then you got to do it. I try to have a plan in place though....

And a cheers to all who love this boating life....

WZ

Oh I am also working over a 1968 18ft. Starcraft Chieften... It no longer has wood in the transom its all aluminum and that pesky huge motor well is gone replaced by it has a new floor and still quite aways to go.. that is for another thread....

 

[chriscraft254]

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Great conversion, little easier I think than on a fiberglass hull conversion.. Nice job on the bracket. How does she come out of the water, any handling issues with the motor set back farther?

 

[WeldZilla]

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

No there have been no issues at all. She just hops right up and goes. The outcome of this project actually exceeded my expectations. From start to finish to the handling and speed of the boat. To the extremely low level of noise put out by the Suzuki outboard. With the original 3.0 liter and cobra outdrive once you got to 3500 rpm you almost had to holler at each other by 3800 you did. the other day on the River at 5850rpm my wife and I were able to talk in a normal no raised voice. It was quite amazing...

 

[jasoutside]

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Oh I am also working over a 1968 18ft. Starcraft Chieften... It no longer has wood in the transom its all aluminum and that pesky huge motor well is gone replaced by it has a new floor and still quite aways to go.. that is for another thread....

We'll need you to get a thread going on this too!

 

[ingalp01]

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Awesome Conversion!!! No doubt you are a master welder, and I love the creativity. I work the same way... Do a little pondering and ciphering and off to work I go, hence the fully customized "T" shaped Gantry so I could pull the engine in my boat. Great job!!! And I'm looking forward to seeing the Chieftan thread as well...

 

[zopperman]

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

This is really one cool thread. Props again on a successful job.

 

[WeldZilla]

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Thanks for the comments and for taking a look. I just re-routed the control cables and ignition wires coming off the control box to tidy up a bit. I am ordering a sheet of 3/16 aluminum this week to sart incorporating fish boxxes and storage in my new found space at the back of the boat. Its going to be great when done!

I'll post more pics as I go....

WZ

 

[WeldZilla]

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Well went fishing today. I got to tell you this has worked out so perfectly that I am even amazed. The Suzuki is getting more broke in all the time
It absolutely flies right up to redline now. I have all my electronics wired back in. I installed new seats. Cant make up my mind about passenger seating yet. Side saddle or a couple plug in posts or a 5 ft. seat across the stern. Here are a couple picks this morning at launch. Well the fishing wasn't so great. I caught a few sub-legal sturgeon, it was still a great day on the water.

 

[CaptainKickback]

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Excellent. I have read a number of discussions on conversion to OBs, but in each case, the person had no experience, just an opinion. I have just started my conversion project (and started a thread for it), so I'm glad to hear your positive results. I hope to get the same.

 

[jasoutside]

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Re: 22ft. Sylvan offshore from 3.0liter OMC to Suzuk iDF140

Cool stuff zilla!