OMC King Cobra

[OMC King Cobra]

I have a 1989 Sunbird Eurosport with a 383 stroker hooked up to an OMC King Cobra. Its shucked from one end to the other. An OMC master mechanic told me that these drives were no good with anything bigger than a 302. Has anyone else heard this? Any suggestions for alternatives?
Thanks
Emory

[gnarley]

Call these guys & ask for Paul or Sid.
PANGBORN MARINE
4204 ISABELLA ST
MIDLAND, MI 48640-8362
989-832-8641
Not Guilty, who posts hear at times, seems to know a lot about these drives & I have heard a little about them as well. The earlier dog clutch design is touchy about RPM engagement & will tear up the upper if shifted at to high an RPM I am told. The later cone clutch style is better & was made in the early 90's as a joint venture with Volvo. Not Guilty & others have 460 Fords somewhat built up & seem fine. Also if you don't change the lube enough depending on usage you can expect to fix it again. The recommended interval is 50 to 100 hours on the drive lube or expect to pay the piper again, changing the lube is cheap insurance.

[not guilty]

Yup, as me pal GNARLEY said , been runnin 'em for over ten years. Sold a boat last year that had the original drive on it since 1992,had 4 different motors in that boat up to 500hp (all BBF)never had a hint of a drive failure.
Have a twin engine now running 425hp BBF's new motors this year on drives w/over 850 hrs.rebuilt one last year due to an unforeseen under water mishap. Other than that no probs.
Cant see where a king couldnt handle a stout small block as tourqe seems to be the real killer.Just take it easy out of the hole and dont jam the throttle at any speed.(I wouldnt advise such behavior on any drive, I value my assets )And as GNARLEY said keep the oil clean. NG

[Dr. Eagle]

The mechanic was full of something, but not good information.
I had a 1989 King Cobra on my 21' open bow daycruiser with a high output (for the time) 350 chevy of 260hp. The drive is basically very similar to a Mercruiser Alpha, but I think it is somewhat tougher. My problem was that getting the shift adjusted was problematic and the shift cables broke regularly (about 300 hours)> I had over 1000 hours on it and I had kicked the engine up to about 300 horses with intake, head and exhaust mods. I did have to replace the forward/reverse gears and dog clutch at about 700 hours. It is not uncommon to have to do the same with the Alpha due to the clutch mechanism.
As I said, same concept as the alpha,with the dog clutch rather than the cone clutch but the gears were actually larger than those in the Mercruiser Alpha. I believe in 1990 or 91 all of OMC's drives labeled King Cobra were newly designed cone clutch models similar to the bravo.
Regardless, mine served as well as any Mercruiser I have ever owned, and the sea water pump impeller is a hell of a lot easier to replace than on any other outdrive system.
Oh and what Gnarly and NG said about changing the oil is absolutely correct. I went to the Mercruiser High Performance Gear Lube (the synthetic blend) and change it often.
[ September 25, 2003, 07:58 PM: Message edited by: Dr. Eagle ]

[markt111]

the important thing for your sfift engagement is to make sure your ESA module (ignition deadening switch) and linkage are all properly adjusted so shifting is done at very low RPM, make sure you have a service manual or have it done by someone familiar with the setup, my boat is an 1988 and the drive was never touched till last year when I changed the gear ratio, and it has not been babied

[Dr. Eagle]

Yes the shifting ignition pulse module (Electronic Shift Assist Module) and micro switch linkage adjustments are critical. Shifting was this drives weak spot, but they were actually fairly robust for a dog clutch system.
OMC unlike Mercruiser did have (I believe) three or four different drives designed for different levels of horsepower. I had the second to the largest, the next size up was usually coupled to ford 460 big blocks. The smaller units were designed for four and six cylinder engines. The largest one coupled to the big blocks was very robust, it had about twice the oil capacity of the drive I had.
OMC did have a "Silent Recall" of the gear sets used in the early units such as my 1989. If you had a gear or dog clutch failure they would replace it with redesigned beveled gear sets vs. the straight cut gears that were originally manufactured. I believe that to qualify for this recall it had to happen in the first five years. Of course it was about 8 years and as I said somewhere between 7 and 800 hours before they gave up the ghost. So I had the honor of paying the $1,500 to get the work done.
As MarkT111 said it really is necessary to have a manual. I bought the factory manual from OMC, but I am not sure where you might come across one of those anymore. I guess you could keep your eyes on ebay.
Bottom line, these drives were just as good as anything else on the market when properly maintained and adjusted.
[ September 26, 2003, 03:06 PM: Message edited by: Dr. Eagle ]

[Outnumbered]

Got my factory OMC manual from here. He's a good guy.
OL
Vintage parts and manuals

[Dr. Eagle]

Old Lavey:
Got my factory OMC manual from here. He's a good guy.
OL
Vintage parts and manuals Man OL you really know your way around. I figured the factory shop manuals would be long gone by now. Good thing to remember.
Not meaning to beat a dead horse, but the OEM shop manuals are a must if you do your own maintenance.

[gnarley]

Dr. Eagle:
I believe in 1990 or 91 all of OMC's drives labeled King Cobra were newly designed cone clutch models similar to the bravo.
Well to clarify things a little bit the cone clutch is similar to the Volvo not the Merc or Bravo. Volvo was the first to use the cone clutch upper & the late model King Cobra uppers were actually designed by Volvo for OMC as a joint venture & share some part numbers as designated by the 385 in the first part of the part number or called JV for joint venture. Volvo & OMC were partners for a short tie before OMC's demise. I think that Merc copied Volvo's cone clutch design once the patient rights expired. Volvo was the innovator if I am not mistaken.

[Dr. Eagle]

gnarley:
Dr. Eagle:
I believe in 1990 or 91 all of OMC's drives labeled King Cobra were newly designed cone clutch models similar to the bravo.
Well to clarify things a little bit the cone clutch is similar to the Volvo not the Merc or Bravo. Volvo was the first to use the cone clutch upper & the late model King Cobra uppers were actually designed by Volvo for OMC as a joint venture & share some part numbers as designated by the 385 in the first part of the part number or called JV for joint venture. Volvo & OMC were partners for a short tie before OMC's demise. I think that Merc copied Volvo's cone clutch design once the patient rights expired. Volvo was the innovator if I am not mistaken. You are correct but that joint venture did not go down until somewhere in the 1993 or 94 time frame. The first OMC King Cobras in 1990 to 1993 or 1994 with the cone clutch were an all OMC design.
The joint venture drive basically took the Volvo upper and the OMC lower and combined them. But it did come along maybe as late as 1995, I am a little foggy as to when exactly it went down. That resulted in the the drive being provided both with OMC and Volvo packages for the next 5 to 7 years or so before OMC went belly up. Then Volvo snapped up the OMC stern drive assets at bankruptcy.
Since Ford now owns Volvo, and Volvo marine, you have to wonder how long before they might switch over to Ford engines.
I think you are right about the cone clutch being a Volvo innovation. Both OMC and Merc copied the drive when the patents expired. And OMC also did the same about 5 years earlier when they designed the OMC Cobra which was basically the same system as the Merc Alpha.
[ September 30, 2003, 08:03 PM: Message edited by: Dr. Eagle ]