Omc Seadrive Question

DUKE1

Petty Officer 3rd Class
Joined
Jul 30, 2006
Messages
96
Hello,

I don't own one of these..but a guy I know does and he asked me the following. Can any Johnson/Evinrude Product (140HP) be swapped over to take the place of a 1983 OMC SEADRIVE 1.6L? He thought he heard that there was a year of Johnson/Evinrude that would fit on the OMC SEADRIVE bracket. Can't find much about this on the web....thought I'd come to the all knowing ones and see what you all had to say.http://forums.iboats.com/images/icons/icon7.gif
Smile

Thanks,
Duke1
 

tashasdaddy

Honorary Moderator Emeritus
Joined
Nov 11, 2005
Messages
51,019
Re: Omc Seadrive Question

be patient, seadrive's are in there on world, someone familiar will chime in.
 

seadrive1

Recruit
Joined
Apr 23, 2008
Messages
3
Re: Omc Seadrive Question

I have twin 1985 115 seadrives it is very easy to replace powerhead on mine any mid 70-1985 johnson evinrude powerhead will bolt right up less then 3 hour job if your mechanically inclined..
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: Omc Seadrive Question

Some V4 crossflows will bolt up and work. There is one thing he'll want to look for when shopping for another block.

If his Sea Drive uses a shift connection than uses a U-joint on the starboard side of the block he'll need a specific block in order to rehook the shift linkage.

On the aft side of the lower pan mount, starboard side, there will be a boss with a threaded hole that holds the linkage. Some outboards from the mid 80's & newer have the boss or enough material to create the boss. If he chooses an early 80's or older, that material won't be there.

Obviously if his SD doesn't use that boss, any late model V4 crossflow will work. Some of the ignition component bosses are different from year to year so he'll have to look at that.

Not all 140's will work. Obviously the 140's from 1985 on are loopers so they won't bolt up.
 

Solittle

Fleet Admiral
Joined
Apr 28, 2002
Messages
7,518
Re: Omc Seadrive Question

The OMC service and parts manuals are a must if you ever have to work on the SD unit. I have a pair of 1987 SD 1.6L engines and have had no problems with the SD. I'm told parts are very hard to come by.
 

GatorMike

Ensign
Joined
Aug 3, 2003
Messages
902
Re: Omc Seadrive Question

As an ex seadrive owner I am reading this thread with a big smile. I got tired of parts men telling me "A seadrive? We don't carry parts for that motor anymore". Finally I started just asking for parts for an 89 115 Jonnson through the years I owned that thing I never found a part that was not interchangeable except parts for the seadrive bracket itself.
 

Upst8co

Cadet
Joined
Apr 29, 2010
Messages
7
Re: Omc Seadrive Question

Hey Guys,
New to the site. Very informational. Just found a 1987 sportcraft 20' with a 140 hp OMC sea drive. (As i have been told by the owner.) Boat is in great shape.What my question is would anyone buy a sea drive? Was not looking for a sea drive just came upon it and it is in great shape. But i am looking down the road if any problems come up. Really don`t know if i should pass and keep looking for a more modern set up... What would this thing be worth with trailer ? Appreciate any help. Thanks !
 

mikesea

Lieutenant Commander
Joined
Oct 1, 2006
Messages
1,830
Re: Omc Seadrive Question

Duke,simple answer to you question is yes.If those engines you describe are those which the transfer will take place with.but ,as said,there was alot of experimentaal stuff that went on.Some had hydraulic steering some had cable.In simplicty,the powerhead will interchange but,he will need the intake manifold off the seadrive because the linkages have different hookups,the lowerunit will interchange but the shiftshafts from the seadrive will need stay with seadrive,I had a few of them,worked on many,and can only say ,very few were EXACTLY the same,they used crossflow engines and loopers,v4 and v6.That said,I found the idea to be good,but there was many faults,one being the powerhead tended to be too low and often backwash could flood the engine alond with a common flooding of the cowling,that also caused the driveshaft to become stuck in the crankshaft more often then standard engines,the lowerseals could pass water and the crankshaft would lose its splines after a while causing a great running engine to suddenly become a screaming ,overheating engine in neutral ,due to driveshaft not turning.most mechanics will tell you to avoid them parts ARE scarce,granted the internals of the powerhead and the lowerunits are shared with standard outboards,but,the bracket assemblies ,bushings,hydraulic hoses,hydraulic rams used for steering and trim and tilt are not common.many guys ,eventually pull the seadrive off,if the powerhead is great,they convert it to standard outboard and put a bracket on the stern after glassing in the holes left from the seadrive unit.Not really rocket science.If you have a seadrive,the best you can do for it is maintain it.Especially pulling the lowerunit fairly often ,I say once a yr.and greasing the driveshaft splines with a good grease like amsoil that wont breakdown from water or heat,clean with fresh water all the lines and rams.There are some GREAT deals on those set ups because many are steered awa .But if you put in mind ,one day,you may convert ,and especially if your mechanical inclined,you can do well because of the bad name the units have.The real pro to it all ,is,the full transome boat you get ,with ability to do any kind of bracket .engine combination you want to do.The controls are interchangable with standard engines of OMC make,excemp for ficht and the etec newer engines.
 

Upst8co

Cadet
Joined
Apr 29, 2010
Messages
7
Re: Omc Seadrive Question

So.... would you guys shy away from a sea drive knowing what you now know?
 

tashasdaddy

Honorary Moderator Emeritus
Joined
Nov 11, 2005
Messages
51,019
Re: Omc Seadrive Question

personally, i like them. not much different than an outboard.
 

Upst8co

Cadet
Joined
Apr 29, 2010
Messages
7
Re: Omc Seadrive Question

Ok that helps. A 1987 sportcraft 20' ,t-top, trailer a 1.6 liter which the owner states is 140 hp. I am hearing it is 115 hp i really don`t know. Boat looks really nice. all painted up. owner states it runs and goes real nice. What would this craft be worth? you know ballpark figure. Is the 1.6 115 hp or 140 hp? Thanks again.
 

mikesea

Lieutenant Commander
Joined
Oct 1, 2006
Messages
1,830
Re: Omc Seadrive Question

What does ALL PAINTED UP mean?.I hope that just means the bottom coated.the reality is,used boats are a dime a doz.Your talking about a boat that is near 24 yrs old.its a SEADRIVE ,that alone makes it unwanted in the world of used boats.Being as honest as I can be,no more than $3000.Thats if everthing is as though it was garage kept.If I wanted a boat ,was willing to buy something 24 yrs old,with a seadrive ,AND the guy really wanted to unload a boat I might would want.Offer $2000,and go from there.Too many people are basing used boat prices on replacement price these days.Many old boat owners are LUCKY to get rid of them.The market the way it is ,put buyers ina buy position.You can get new stuff at rock bottom prices with litytle down.The industry is starving.By the way ,that engine isnt very efficient compared to todays engines.You need to weigh the future maint cost as well.Because of scarcity of the parts I mentioned.Put your self in a mindset that,if the engine blows tomorrow,what are your options.Get ridof a boat NOBODY will want.OR,fix what you have.That means getting a good used standard outboard eng.and putting a bracket on the hull after some fiberglass work.If you do it yourself ,with price of a good used 1990 -95 eng,a bracket your looking at 4-5000 thousand .You then have your original investment of 2-3000 thousand.So for 6-8 grand ,you can buy something newer and nicer ,that if you want to sell in a yr or 2 you might be lucky.Right now,you shooting the dice.That all said,it might be a low hr.well maint boat and worth the gamble.I do not suggest it though if your intent is used all weekend long in a salt environment.The seadrive components will sooner or later get ya.The hydraulic hoses for the trim and tilt were going for 300 a piece 10 yrs ago when some dealers could still get em.Sorry about all that,hope I answered your ??Good Luck.Mike
 

Upst8co

Cadet
Joined
Apr 29, 2010
Messages
7
Re: Omc Seadrive Question

I hear positive and i hear negative . It is expected . ALL the replies are very helpful. He is asking $3500.00 Negotiable. This is the least priced 20' centerconsole with t-top i have found. And it does look good. But i truly understand what you guys are telling me. And i am not wealthy so i do need to look down the road a bit for maintenance and repairs. Wish i could figure out how to put up a picture so you could see it. Thanks again guys ! This forum is great.
 

ezmobee

Supreme Mariner
Joined
Mar 26, 2007
Messages
23,767
Re: Omc Seadrive Question

Sounds like a pretty good deal to me. It's not like we're talking about a yamaha sterndrive here or something equally horrible.
 

mikesea

Lieutenant Commander
Joined
Oct 1, 2006
Messages
1,830
Re: Omc Seadrive Question

OK ,your upstate ,is it a LAKE boat?is it something you really like,then ,I like the nego.part.You do what you think is in your budget.If its a freshwater,low use boat,you probably will be fine.My experience is ,saltwater.I have seen MANY freshwater boats that take your breath away in the newness,In fact ,Im kicking myself because there was a STEAL on a go fast boat in Ma,I WANT for 300o ,1974 classic,metallic paint,garage kept,and I would need pay 1500 to ship.So.used boats are a gamble,the Seadrive ,is a neg.but was a pos.in the day.If its clean,comp.good,runs great ,,you want a boat,he wants to get rid of one,make the offer.Worse that can happen is,you put some bucks in it down the road.A freshwater,claen boat does hold a value beyond the book .
 

Upst8co

Cadet
Joined
Apr 29, 2010
Messages
7
Re: Omc Seadrive Question

I spoke with the owner a little more in depth. He tells me he has owned it for three years. The guy he bought it from had it in storage for ten years. He bought it, cleaned on it,and replaced some electrical parts and ran it on a freshwater lake. does knot know beyond that. Boat is in great shape. Has ship to shore radio and depth finder. Looks to be very low hours as owner states. He says he sportcraft just don`t use it as much as he uses his small tiller and needs the room for parking. End result i bought it for $2,500.00 bucks. Got him down $1000.00 bucks ! Heck the trailer with electric winch has got to be worth something , right?
 

ezmobee

Supreme Mariner
Joined
Mar 26, 2007
Messages
23,767
Re: Omc Seadrive Question

Great deal! Post some pics if you get the chance. Congrats!
 
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