1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5"

CodyGrizz

Seaman
Joined
Nov 20, 2006
Messages
65
Howdy. First off I THINK its a 120hp engine..there is no "120" or "140" on my valve cover like I see in most engines, how DO I know which I have??

Anyways, I was wondering folks thoughts. I had my carb rebuilt last summer and never got it out but in setting dwell on muffs to TRY getting it out, it wouldnt run right unless someone is sitting over the carb fethering the carb. So I am thinking about replacing the carb..shouldnt be more than $250 or so I would hope. Any ideas on what carb I should use? 2 barrel? 4? I know the carb I have on my boat is NOT like the one my dealer had in his manual. Weird we thought.

Also I am tired of setting dwell and hoping its right. Should I just get rid of points and go electric conversion? Any links to go places to get kits? Go with a kit or a whole new distributor? New coil? Anyone??

I replaced he plugs last year, so they should be fine. Could go with new wires but mine look good. its on a 19.5' Bayliner Capri open bow runabout..what should I be looking at for top speed? I put on Smart Tabs and it sure scoots dang smoother and feels faster, but what should I be hitting for speed? Whats this boat weigh? I have looked everywhere, and my title doesnt say..so I have to ask!
 

mark.p

Cadet
Joined
Jul 23, 2006
Messages
26
Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

I found out the weight of my boat by entering it into the NADA website. It will tell you if you give it the right info.
www.nada.com, go to boats, input info.
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Best thing you could do right now is call Bayliner toll free at 877-861-6494. Have your hull ID number handy and they can tell you what came with the boat originally.
Of course if it isn't the original engine, that won't help,
Pictures would help, along with any model and serial number tags or cast numbers you may find on the engine somewhere.
 

Reel Poor

Vice Admiral
Joined
Jan 29, 2005
Messages
5,522
Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

If it has a harmonic balancer on the front of the crank, It's a 3.0L/140HP
If it's the 2.3 liter, thats a Ford motor and has an overhead cam and timming belt on it. (120 hp I think)

2.3L, 1987-90,.....R2,2GE........17086107,.....
SUPERSEDED TO:........................................Y39-4
y39_3f.jpg


2.3L, 1987-90,.....H2-2300........R80313........Y42
y42_11.jpg


3.0L, 1987-90,.....R2,2GC.........17086064.....Y39-1
y39_2f.jpg


NOTE on the Y-39 carbs the chokes could be hot air or electric......And the fuel inlet could be different.....Depends on the exact application. I would also recommend the origional style 2 barrell carb.


 

CodyGrizz

Seaman
Joined
Nov 20, 2006
Messages
65
Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Thanks for the replies. I will take pics this afternoon if it stops raining (its Florida..its better than snow!!). My carb looks like the 3rd one. Weird thing is there was a hole kinda that I thought should have something on it or attached to it, yet the dealer didnt have a clue. They said it was an un-needed vacume hole and they just put a plug and JB Welded it. (Yes,..they ARE an OMC Dealer even..). I found a new carb for like $200 one time online, had a new distributor found but lost both the links in a computer crash.:|
 

CodyGrizz

Seaman
Joined
Nov 20, 2006
Messages
65
Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

picture019xq2.jpg
 

CodyGrizz

Seaman
Joined
Nov 20, 2006
Messages
65
Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

There is the carb with the part they sealed up. Strange eh? I ill add more pics of the engine so maybe someone can tell me what size it is!!

picture021ci8.jpg


picture022rp5.jpg
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Perfect. It says 3.0L on the valve cover, that's a 140.
The 120 was a 2.5L engine.

You also need to hit the enter key and put a couple of spaces between each picture so you don't have scroll sideways to read and look at everything.
 

CodyGrizz

Seaman
Joined
Nov 20, 2006
Messages
65
Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Sorry about that. I did hit the enter, it put something between my pics even..dont know what the heck THAT is!!

So, why did they seal that part of my carb? Whats spose to go there? That carb look right for my engine? The dealer back in Iowa had the 1st carb showing in the factory service manual. I think a new/reman carb is the way to go, just need to know WHAT carb I need. Would a 4 barrel be better or the 2? Vacume choke? etc etc.

Thanks again guys!
 

Reel Poor

Vice Admiral
Joined
Jan 29, 2005
Messages
5,522
Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Give these guys a try. I've hade great luck with them.

Just copy and past in your address bar.

marinecarburetor.com/Y39RochesterCOT.htm
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Cody, you can edit your post and fix it.
On the left side of your post you want to edit, just under the REPLY + QUOTE button is a dropdown menu that says --Interact-- in it. Just click the arrow and choose "Edit Post" add some spaces and delete the dead link and it will look fine.
 

CodyGrizz

Seaman
Joined
Nov 20, 2006
Messages
65
Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Heeeey..editing rocks!! Thanks!

Do I want electric choke or hot air choke (I know I have hot air..didn't know if I wanted to convert). I assume the float and everything is set, all I need to do is adjust idle screws? (which I hope starting setting recommendations are included.)

Also..thoughts on a distributor swap or electronic conversion? Worth it? Companys?
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Do I want electric choke or hot air choke (I know I have hot air..didn't know if I wanted to convert). I assume the float and everything is set, all I need to do is adjust idle screws? (which I hope starting setting recommendations are included

Weeeeeeeeel the choke has nothing to do with floats or idle adjustment. If you don't know how to set a choke or even the basic principals of what a choke is supposed to do, why or how, then you probably should just leave it alone.

Same with the electronic ignition. How will your conversion affect the ESA system? Can you build electronic parts with resistors and diodes etc.?
 

CodyGrizz

Seaman
Joined
Nov 20, 2006
Messages
65
Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

I know it has nothing to do with it. I was asking if it was best to convert, if it would make a difference on this boat/engine combo. I build import bikes and auto, not boats, but can do a thing ot 2 on the engine I reckon. I just hear so many good and bad things about this engine I figgured others have dealt with things and would be able to say "not worth it" or "best dern thing I did" on stuff. I know on our bikes little things like different coils or carbs makes a HUGE difference depending on year/make/size engine..figgure same applys to boats, some things just work and others dont.

And I asked about the idle and float..as in do they set them at the factory. Our aftermarket carbs usually still need proper jetting, shims, and adjustment..boats the same or more "plug and play"?
 

Reel Poor

Vice Admiral
Joined
Jan 29, 2005
Messages
5,522
Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

An identical replacement carb should be plug and play. It may require possible choke, idle air mixture, and idle speed adjustment.

As far as the ignition system goes there are conversion systems avaliable. I can't recommend any but if you persue the option be sure to do your homework. The ESA (Electronic Shift Assist) requires an additional componant to make the converted ignition system to operate properly.
 

tashasdaddy

Honorary Moderator Emeritus
Joined
Nov 11, 2005
Messages
51,019
Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

here's a great source that is local National Carb. 904 636 9400. new facility is on Bowden Rd. this is a National Company, that gives hometown service.
 

cobra 3.0

Lieutenant Commander
Joined
Jul 31, 2003
Messages
1,797
Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

I have the exact same OMC engine. I dunno why do you assume the carb needs replacing? It's probably just poorly adjusted. I have yet to see a carb wear out. Have you adjusted your idle screw, two mixture screws, and maybe the auto choke?

(...and then did an engine timing, set dwell and point gap, fresh plugs, checked compression)

There are no 4 barrel carbs or any other modifications for your engine. The only thing you can do is go with an electronic ignition.

If you want to go electronic, I have done it with a Pertronix system. (They have a website if you google them). Your OMC requires that you put some resistors in line( a plan is supplied on the Pertronix site). Nothing really complicated...

However, the Pertronix system really doesn't improve much of anything other than making it run a little smoother and saving the "joy" of ajusting dwell and point gap.

Sounds like you need a manual and/or a knowledgable friend...or you'll be throwing money at it in useless directions.
 

CodyGrizz

Seaman
Joined
Nov 20, 2006
Messages
65
Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Have a manual, the Clymer style the OMC Dealer sold me. And carbs go bad quite often in bikes, I can only assume they do so as well in boats. Carb was rebuilt and still it doesnt act right (and yes, dwell was set/timing, plugs, compression). I know this feeling the engine has, again I am in no way new to engines, just boat engines (and every thing has their own quirks). I have had bikes brought to me that you can rebuild, sync, and hope and still run like crap. Throw a new set on..runs like new again. Maybe my engines that way..thats why I asked. And yes, I would LOVE to run smoother. Everyone keeps telling me "that engine just runs rough" and I have a hard time believing it or understanding why it would. Seems like they are decent engines..they made em long enough!

If buying a carb for $188 makes ANY difference, money well spent. If whatever an electronic conversion costs makes it run smoother and more reliable..well spent. I am planning a 4.3-5.0 conversion if its possible with my outdrive (hear yes and no's..change gearing..etc) and I feel it is worth it as I love my boat..dont think it will be going to anyone else any time soon, so its worth it to me. But then again..thats me!!
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Whatever carb you get, make sure it's a MARINE carb, not an automotive. It's all about safety issues, not how they work.

As far as changing to a larger engine, I've repowered several of that size boat with V6's. Just put a Volvo V6 MPI with a Duo Prop in an 87 model. It runs nearly 50mph with 4 people aboard and planes in just a few seconds. However, you can't use your outdrive for a V6 or V8. The 3.0L engines used a lighter built drive, plus the gear ratio wouldn't work for a V engine (NO, changing props won't do it)

outhouse.jpg
 

CodyGrizz

Seaman
Joined
Nov 20, 2006
Messages
65
Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Re: 1989 OMC Cobra 120hp questions..in 1989 Bayliner Capri 19.5

Hmm..what all do I need to do the 4.3 swap? I assume engine/out drive/throttle? How much am I looking for a used setup? I mean I could sell my engine/outdrive to offset my costs, that would help. I think it would be worth it..I would love to have more power in my boat..I would REALLY love a 5.0 as I know that was an option for my boat year/model.
 
Top