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Changing from inboard to outboard

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garrett_k

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I am looking for info on changing from a 140 OMC inboard to a 135 murc outboard how difficult is it ? Has anyone done it in the past? is the 135 murc to heavy the boat is an 18 foot star craft. i have had the omc engine rebuilt and have two legs for it but cannot get the leg to liftup. I have tried changing thr tilt moter new shims new wiring etc; no luck i want the omc gone. The water at my doc is low and the leg sits in the mud. i like the boat but cannot use it for two years now any advise on the change over would be helpfull
Thank you.
 
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i have had the omc engine rebuilt and have two legs for it but cannot get the leg to liftup.

Must be a girl then.

I'm guessing the trim pump hoses are switched around or the wires are. Assume your trim pump is filled up with Auto transmission fluid.

Meh, the boats not worth much so even if you screw it up you aren't out much more than your trouble. Usual way is to use an outboard bracket rather than rework the transom. You could make one yourself or scrub thru ebay for a used Armstrong single.
You'll have to plug the transom hole with epoxy and plywood.
 
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Hi, I have just finished this conversion. I had an OMC 4.3l V6 with Cobra, nothing but problems and expense, and lilke you I wanted it gone. I had the engine and drive removed, the transom hole was filled in, ply and glass. All done by professionals. Next step was to have a new duckboard / outboard pod built on the transom. Then I had a econd hand 200HP Yamaha installed. All up it cost around AUS$14,000. I really like the boat and didn't want to sell it. It now performs and handles better than ever, and is now reliable. I will never own a boat with a sterndrive again. Outboards for me. Hope this helps. David
 
garrett_k said:
I am looking for info on changing from a 140 OMC inboard to a 135 murc outboard how difficult is it ? Has anyone done it in the past? is the 135 murc to heavy the boat is an 18 foot star craft. i have had the omc engine rebuilt and have two legs for it but cannot get the leg to liftup. I have tried changing thr tilt moter new shims new wiring etc; no luck i want the omc gone. The water at my doc is low and the leg sits in the mud. i like the boat but cannot use it for two years now any advise on the change over would be helpfull
Thank you.
Click to expand...
Well, the drive is not the reason that the trim/tilt won't work. Have u checked the solenoids? As far as switching from an i/o to an o.b., it's a major job & if u can't do the work yourself the labor costs alone will hit u hard, not to mention the cost of a new outboard. If u want to get rid of the Cobra, I would consider changing over to an SEI sterndrive. The cost will run u about 2k. That includes the conversion kit which will replace the Cobra pivot housing with an SEI & a new outdrive which is an aftermarket Merc. They offer a 3 yr. warranty. It will be far cheaper than what u are considering with the added benefit of getting rid of the Cobra, which are dinosaurs. In the meantime, check those solenoids.
 
ummmm Mr Kracker, I know you are never wrong as you have told all of us but what you have missed here is that Garrett actually has an older OMC (Stringer drive) therefore there would need to be some extensive transom rework in order to fit the SEI drive, he does not have a Cobra. (sorry, couldn't resist)
 
A similar nice bowrider or closed bow boat set up for a 135 O/B can be found locally for around $500 any day of the week.... the value of old boats is in the motor, the hulls are worth very little... often free

converting an i/o boat to OB rarely ends with success or decent performance

kijiji or craigslist search "no motor"
 
Here is a old post i put up to try and help you with the tilt.

So you have a stringer out drive that won't tilt up, or it tilts up very slowly, or you need to help it up physically. Maybe it doesn't move at all.

Here is a step bye step guide to fixing it. A manual would be very helpful.

1- A fully charged battery is imperative.

2- Disconnect the battery and clean the battery posts. Are the cables good?

3- With the battery disconnected, clean all the connections on the port side, solenoids. Don't forget the grounds.

4- Clean connections to tilt motor. Two wires.

5- Connect the battery.

6- On the out drive port side, there is a clutch housing. Four screws hold on
cover. Pull that cover. May be full of water. They all leak.

Two things you can do at this time.

A- Clean out the housing with clutch installed.

B- Remove the clutch and rebuild the housing. New seals.

If you chose A, Spray the clutch with brake cleaner. Make sure it's as clean as you can get it. You might have to spray it a few times. Blow it dry. Spray the the clutch with penetrating oil. Pack the housing with grease, and install cover. Don't over tighten the screws, can bind the clutch.

If you chose B, remove all the components of the gear housing. Soak everything in Acetone overnight. Rebuild housing, new seals. Blow dry the parts, soak them all in motor oil for a hour or two. Install parts. Pack the housing with grease. I know it calls for 30 weight motor oil. Trust me pack it with grease. Install cover.

7- Gently pry off the rubber bumpers. Don't mix them up, pump grease in the zerks. Install bumpers.

At this point the drive should move up and down easy. If it doesn't, you need to pull the tilt motor. Test motor and replace or rebuild. Make sure the hammer blow coupler is good or replace. Don't forget the gasket, on the tilt motor. .

Good luck!

So lets say your tired of that drive and motor setup, you could sell it and buy the boat with the motor on it you want.

Or.... You pull the motor and everything else in the engine bay and the drive sell them on ebay.

You cut a piece out of another boat and fill in the hole in the transom. Then install 2 pieces of stainless steel one on the inside and one on the outside and cover the entire transom, inside and outside.

Install a gill bracket and hang a outboard on the gill bracket. Thats the way i would do it.

You will be into this boat with so much money when your done your will never be happy thinking about it.

Ohhh Kracker my man, my main man Kracker keep your chin up, even a brokin clock is right twice a day. HAH !
 
boatin_bob said:
ummmm Mr Kracker, I know you are never wrong as you have told all of us but what you have missed here is that Garrett actually has an older OMC (Stringer drive) therefore there would need to be some extensive transom rework in order to fit the SEI drive, he does not have a Cobra. (sorry, couldn't resist)
Click to expand...
Well, thanx to Bob & the Chief for settin' me straight on this one. Hey, what can I say. Yea, yea, I know I was askin'for it..........................................
 
It takes a big man to admit he's wrong, glad to see you were up for it....of course this is all just in fun....(no hard feelings)
 
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