OMC to Merc swap in 1996 Sundowner 195

[widowson2]

Hi all need some help. Swapping from OMC 305 to 350 Merc. Engine, inner and outer and outdrive. Boat has a 8 pin harness and 350 Merc has a 9 pin. Do I need to change boat harness or engine harness? Or is there something else I need to do?

 

[Lou C]

If you can compare the harnesses & find out what the extra wire is for with Merc you might be able to add that wire assuming all the rest have the same function.

 

[nola mike]

If you can find a wiring diagram of the boat harness and post it here you'll get a better answer. Better yet, diagram of both harnesses.

 

[matt167]

1996 OMC is a Volvo SX. Unless something is wrong with the drive. Just put the OMC stuff on the Merc engine

 

[Scott06]

Hi all need some help. Swapping from OMC 305 to 350 Merc. Engine, inner and outer and outdrive. Boat has a 8 pin harness and 350 Merc has a 9 pin. Do I need to change boat harness or engine harness? Or is there something else I need to do?

Do you have the harness out of the donor boat? you could cut the connector off and splice onto your existing boat harness. Or get a used boat harness for the plug. I think this 3 ft harnes could be spliced in to boat harness as I believe the engine has female pins

I/O Engine Wire Harness + Options 3ft -35ft

3' length I/O engine harness has a molded 8-way on one end and round 9-way, ninth wire is tan/blue. The harness is spiral taped. Fits most inboard engines. Standard lengths available are: 3', 10', 16', 18', 20', 25' & 35'.Select from the drop-down men

www.michiganmotorz.com

Given Lous comments about the 1996 being a Volvo SX not the joint venture or earlier cobra I suspect you existing power pack is older than 96.

The key hole in transom is the same for Cobra, volvo sx, and merc so should be relatively easy unless stringers or transom are rotted.

 

[Lou C]

The joint venture drives are the exact same as a Volvo SX of the same year. Only difference is that the OMC version was painted OMC charcoal & has an OMC model # plate but if you look close it says made by Volvo Penta marine products LLC, Lexington Ky. That was the factory that OMC built for the Cobra drives. It all wound up getting sold to Volvo. Cut out & stringer layout should all be the same. If you have a Joint Venture Cobra it is a Volvo & if the drive & transom mount are good I’d just keep it. Why bother changing? Esp if you have a GM engine.
JV years:
1994-1998.
Only exceptions is some engines came with the OMC King Cobra cone clutch which is totally different. Usually seen on GM 454s and Ford 351s.

 

[widowson2]

Bought the boat with no engine, drive or inner/outer gimbal. Bought the engine as a drop in so no donor boat . I realized today upon closer look that the one pin on the 9 pin is empty. So I may be fine. Thanks for all the help. Im gonna need it with this project.

 

[Scott06]

Bought the boat with no engine, drive or inner/outer gimbal. Bought the engine as a drop in so no donor boat . I realized today upon closer look that the one pin on the 9 pin is empty. So I may be fine. Thanks for all the help. Im gonna need it with this project.

Yes correct the one pin is unused. I believe they should work. You are smart to get a complete drop in vs piecing it together

How is the structure of this boat in terms of transom and stringers?

 

[widowson2]

Checked the transom and stingers with a hammer all are solid. Can see the transom wood through the keyhole. No delamination.

 

[widowson2]

 

[widowson2]

Boat is clean for age

 

[Scott06]

Boat is clean for age

Would agree strange someone janked the entire drivetrain out of it given the condition?

 

[widowson2]

The story I was told was someone stole the outdrive, intake man. and carb, exhaust mans and heads off the engine during winter storage. He sold block and inner and outer to a guy. I dont know if true or not. I got the boat and trailer for $800 he wanted $1200

 

[Scott06]

The story I was told was someone stole the outdrive, intake man. and carb, exhaust mans and heads off the engine during winter storage. He sold block and inner and outer to a guy. I dont know if true or not. I got the boat and trailer for $800 he wanted $1200

Outdrives are common to get stolen and the insurance is normally on the boat owner not storage location.... People should just keep their effing hands off what is not theirs...

 

[widowson2]

Outdrives are common to get stolen and the insurance is normally on the boat owner not storage location.... People should just keep their effing hands off what is not theirs...

I agree. I park my boat where I park my tractor trailers. We have trucks in and out all hrs. Locked gate a security cameras everywhere

 

[Lou C]

I pull the drive in the fall & it stays in my locked garage. Not that anyone is looking to steal a 1988 OMC Cobra lol.

 

[nola mike]

Checked the transom and stingers with a hammer all are solid. Can see the transom wood through the keyhole. No delamination.

Hammer test is lousy. Drilling some holes in tension and stringer imo it's the only fool proof way to test condition. Everything is accessible with the engine out, and definitely worth doing to make certain you're not putting lipstick on a pig