88 King Cobra 460 bang, comes out of drive

[radzikbjj@gmail.com]

Hi everyone, been looking around and doesn’t seem to be that common issue, or maybe it is.
Very new to OMC, other boats had/have Mercs.
Did read on the shifting issues a ton and fixed some issues, but here is the big one. Actually 2 issues.

1. while accelerating, around 3000 rpm plus minus, a loud bang and jerk happens, very scary... feels like it kicks out of the gear and then comes back in. Happens, almost every time, but cannot predict when. Sometimes it goes for 5 minutes at plane at 3500-4000 and BAAAMMM!!!!! Drop it down, gently accelerate and its fine for a long drive across a lake.

I played with cables. Lower cable is new. Wasn't adjusted well. I did. Upper cable seems to be adjusted finally by me this weekend, but I am pretty sure it needs to be replaced, it is slightly bent at the connection to the rocker area.

yet to take it out again after adjusting. Has anyone encountered a similar issue?

2. Smaller issue, but still an issue. Lower speed steering is late. Tunr the wheel, and boat reacts 3-5 second late. Or it can go straight for few seconds and then all of the sudden it starts to turn. So the driving a narrow canal is a pain, always anticipating self turning, so I roll the wheel a bit back and forth all the time. High speed is normal response.

Any advice is appreciated. thank you.

the boat is 1988 Bayliner 2655

 

[radzikbjj@gmail.com]

Oh yeh... cannot find a part number for the upper cable. Can anyone point me to the right one?

 

[Faztbullet]

My honest opinion is sell it as parts are hard to find and no tech in their right mind will fool with one . You likely need a 5° gear set, clutch dog, input shaft as splines like to twist from banging and cable. You will need the bell crank and shift cable tools to set up cable

 

[PITBoat]

2. Smaller issue, but still an issue. Lower speed steering is late. Tunr the wheel, and boat reacts 3-5 second late. Or it can go straight for few seconds and then all of the sudden it starts to turn. So the driving a narrow canal is a pain, always anticipating self turning, so I roll the wheel a bit back and forth all the time. High speed is normal response.

Any advice is appreciated. thank you.

the boat is 1988 Bayliner 2655

That's something I noticed trying to recover to the trailer on my very first outing. Part of the "How do I get rid of this thing?" reaction I had a bit of that first day. So, completely normal in my limited experience.

I just try to keep a bit more speed up, and have learned to anticipate it instead of reacting to it at slow speeds. If you are reacting to it in that regime you're already behind.

 

[radzikbjj@gmail.com]

My honest opinion is sell it as parts are hard to find and no tech in their right mind will fool with one . You likely need a 5° gear set, clutch dog, input shaft as splines like to twist from banging and cable. You will need the bell crank and shift cable tools to set up cable

Not the answer I look for, but I also understand it, giving the history and issues of OMCs. But parting the engine and getting another one is just so much pain.

The main questions is - what is the reason for that bang? I want to understand the reason and then go from there. It'll be out of water in couple of weeks, so "dismembering" can start then and go on for the off season time.

 

[southkogs]

Not sure what's happening on the first issue for you. My first thought is a shaft spline or gear tooth missing and the set has to hit the right time to jam up on itself. Any metal shavings or pieces in the gear lube?

Second issue sounds more like bow wander that is typical at low speed for I/Os. I don't know if OMCs do it more than Mercs, but on most I/Os (and some outboards) water flow, low rudder surface and the effects of prop torque will cause the bow to shift back and forth at low speeds. Sometimes trimming up can help this, but almost every I/O boat will deal with it.

 

[Lou C]

That bang is the well known Cobra problem of the drive jumping out of gear due to the clutch dogs rounding off. This is because if your cable was sticky or adjustments did not give adequate travel in fwd and/or reverse it would cause clutch dog wear and once it gets to a certain point it will not stay in gear. So the cure besides making sure the cables and adjustment are right, is a new clutch dog and fwd & rev gears. In the letter OMC sent to owners when they were recalled, they described this exact problem. It was later found to not be the 2* gear sets but a supplier changed the spec on the cable and the cables had too much drag. A Cobra cable has to have less than 2.5 lbs of drag.
I've kept mine adjusted the 18 years I have it and never had it do that....but I agree good techs and some parts are hard to find now seeing as how the original dog clutch models have not been built since 1993 that's 27 years ago!

When my Cobra needs replacment I may bite the bullet and convert it to the Volvo SX, its a fairly easy swap and at least people will work on them and parts are available!

 

[Lou C]

The upper cable that goes to the control is nothing special just a standard OMC style control cable.

 

[PITBoat]

Second issue sounds more like bow wander that is typical at low speed for I/Os. I don't know if OMCs do it more than Mercs, but on most I/Os (and some outboards) water flow, low rudder surface and the effects of prop torque will cause the bow to shift back and forth at low speeds. Sometimes trimming up can help this, but almost every I/O boat will deal with it.

Making smaller steering inputs helps too I think. Dial in what you think you need before needing it and wait a second. Like a big ship. Not the small inputs part, but the waiting...

 

[radzikbjj@gmail.com]

Making smaller steering inputs helps too I think. Dial in what you think you need before needing it and wait a second. Like a big ship. Not the small inputs part, but the waiting...

Thanks for the input, gents.

Yeh, i've experienced it with other boats and know what you're talking about. This time seems a bit more extreme, the turning is pretty sharp. It feels like a delay in hydraulics or something. Can it be the power-steering pump? the belt is not tight enough? Air in the system? I know I know, al those are maybe possible.

 

[radzikbjj@gmail.com]

That bang is the well known Cobra problem of the drive jumping out of gear due to the clutch dogs rounding off. This is because if your cable was sticky or adjustments did not give adequate travel in fwd and/or reverse it would cause clutch dog wear and once it gets to a certain point it will not stay in gear. So the cure besides making sure the cables and adjustment are right, is a new clutch dog and fwd & rev gears. In the letter OMC sent to owners when they were recalled, they described this exact problem. It was later found to not be the 2* gear sets but a supplier changed the spec on the cable and the cables had too much drag. A Cobra cable has to have less than 2.5 lbs of drag.
I've kept mine adjusted the 18 years I have it and never had it do that....but I agree good techs and some parts are hard to find now seeing as how the original dog clutch models have not been built since 1993 that's 27 years ago!

When my Cobra needs replacment I may bite the bullet and convert it to the Volvo SX, its a fairly easy swap and at least people will work on them and parts are available!

OK, that's the info I was looking for. THANK YOU.

Spending $10K on Volvo SX plus labour is not in my plans But I do have access to a couple of good shape drives and a tech who has tons of experience with these dinosaurs.

 

[Lou C]

Well if your tech can rebuilt one then as long as you have a good smooth moving shift cable and its kept in adjustment with a new clutch dog and lower gears, it can last a very long time. These should shift very easily into and out of gear any stiffness means that something is wrong.

With the Cobra there are certain things you have to keep on top of, beyond what I mentioned there is a bell crank in the pivot housing (bell housing) that can get crudded up and sticky if the gasket between it and the drive leaks, when you pull the drive at the end of each season this area should be cleaned out and packed with Evinrude triple guard grease. The gasket, should be coated on both sides with OMC gasket sealer or Merc Perfect seal.


When refilling the drive with gear oil you have to follow the OMC procedure, there is a dipstick in the top cover (like a Volvo SX) and a drain plug , on on the lower end of the bullet and a fill plug near the joint between the upper and lower gear housings. The lower one you drain from with the dipstick removed. Removing the dip stick allows it to drain faster. After it drains you replace the drain plug (with new fiber washer gasket) and remove the fill plug near the joint between the upper and lower and hook up your gear oil pump to this fill hole. Now with the dipstick unscrewed up top to allow air out you pump in approx 2 qts of gear oil, put the dipstick back in loosely to check on how much is in there....when it reads full, replace the dip stick (new washer) and quickly remove the gear oil pump and replace that drain plug (new fiber washer). Then remove the dipstick again, let it sit for a bit and re-check. If its a bit low you can add more from the top hole that the dipstick fits into. This ensures that any air bubbles escape and you get the right amount of gear oil in the drive.

What you have with the Ford 460 is known as the Baby King drive, it is a normal Cobra upper gear housing mated to an HD lower unit from the V8 Evinrude outboard. The parts for these are more rare than the standard Cobra used on the 4 cyls, V6s and small V8s. Properly built and maintained it will last as well as anything else though.

 

[radzikbjj@gmail.com]

Well if your tech can rebuilt one then as long as you have a good smooth moving shift cable and its kept in adjustment with a new clutch dog and lower gears, it can last a very long time. These should shift very easily into and out of gear any stiffness means that something is wrong.

---------------- upper gear housing mated to an HD lower unit from the V8 Evinrude outboard. The parts for these are more rare than the standard Cobra used on the 4 cyls, V6s and small V8s. Properly built and maintained it will last as well as anything else though.

Lou, thanks for all this info, very very needed. Being new to OMC, knowing the main issues when purchasing the boat, now more info like this the better. I personally cannot believe that an engine can be crappy engine if they run for so many years. All engines have issues. Yes, Mercs (and I am familiar with GM small blocks) are more available and techs are more familiar with them, and there are more parts for them, but why not an engine of that displacement from a good company? Yep they screwed up with the engineering of those cables/gear switching, but maintain it, lube it, care for it and they will live. My neighbour has also 30 yo boat that he boat new those years back with CObra on it, and he had zero issues with it, besides few maintenance repairs and cable replacements. He is probably the main reason I got this boat (again), the price was too good.

One extra question... anyone converts to duoprop on these king cobras? Good, bad, possible impossible?
Thanks again.

 

[Lou C]

Impossible, duoprop on Volvo SX and Merc Bravo has cone clutch shifting in the upper gear housing, Cobra has dog clutch shifting in the lower unit like a Merc Alpha....
There was a King Cobra (Daddy King) used with the Chevy BB engines that had cone clutch shifting in the upper gear housing but to knowledge it was never offered in a DP configuration and is even more rare than what you have.

the main problem with the Cobras was defective shift cables (recalled) and a very confusing procedure to adjust the cable. This was simplified in later manuals and OMC came out with 3 alignment tools to make it much easier. I used these when I did mine and it really was not hard, you just have to follow the steps in order starting with shift rod height (in the lower gear housing) then set up the transom cable, then adjust the remote cable. The goal is always to have equal throw into FWD and REV on either side of neutral and make sure that, the ESA works and your engine is in good enough tune that it can idle at 600 rpm. The ESA will engage only when there is pressure on the shift cable from boat being in the water, with water pressure against the prop. It will lower the rpms to 450 for a split second to allow the clutch dog to release the gear you are in....

 

[Scott Danforth]

its not that the Ford engines are bad. its that Ford pulled out of the marine market and parts are no longer available......especially for fuel injected motors......then OMG went out of business and the drive is no longer supported.

 

[Lou C]

yep, the Ford motors were not bad but for the 460 for a while you could not get couplers, or exhaust manifolds. The drive parts for the regular Cobras are not bad to find, I have some spares in my garage just in case (Y pipe, steering actuator, trim rams). I stuck with it because I have had very little trouble with the drive or transom mount. Really excellent durability in a salt water environment 6 months out of the year (moored) for 15+ years. Can't complain one bit about it.

 

[radzikbjj@gmail.com]

Impossible, duoprop on Volvo SX and Merc Bravo has cone clutch shifting in the upper gear housing, Cobra has dog clutch shifting in the lower unit like a Merc Alpha....
There was a King Cobra (Daddy King) used with the Chevy BB engines that had cone clutch shifting in the upper gear housing but to knowledge it was never offered in a DP configuration and is even more rare than what you have.

the main problem with the Cobras was defective shift cables (recalled) and a very confusing procedure to adjust the cable. This was simplified in later manuals and OMC came out with 3 alignment tools to make it much easier. I used these when I did mine and it really was not hard, you just have to follow the steps in order starting with shift rod height (in the lower gear housing) then set up the transom cable, then adjust the remote cable. The goal is always to have equal throw into FWD and REV on either side of neutral and make sure that, the ESA works and your engine is in good enough tune that it can idle at 600 rpm. The ESA will engage only when there is pressure on the shift cable from boat being in the water, with water pressure against the prop. It will lower the rpms to 450 for a split second to allow the clutch dog to release the gear you are in....

Lou, thanks again for such detailed info, but you're digging a whole for yourself with all these awesome answers...I will bother you more and more LOL.

Are you talking about something like this:
https://www.amazon.ca/balikha-Align...ignment&qid=1600348481&rnid=5690384011&sr=8-3

and where can I get that updated manual for the motor, or I guess, specifically for the gear switching cables installation/adjustments?

 

[Lou C]

yep those should work, there is a 3rd tool to measure the shift rod height on the lower gear housing. however, that can be measured with a ruler and t square if you are careful.

Manuals, do a search on ebay you can still find OMC factory shop manuals. They are the best but also look at midnight wolf omc parts webpage, he has updated instructions on his side and similar tools and also the stuart hastings OMC adjustment article which has been on the web for like close to 20 years.

 

[radzikbjj@gmail.com]

yep those should work, there is a 3rd tool to measure the shift rod height on the lower gear housing. however, that can be measured with a ruler and t square if you are careful.

Manuals, do a search on ebay you can still find OMC factory shop manuals. They are the best but also look at midnight wolf omc parts webpage, he has updated instructions on his side and similar tools and also the stuart hastings OMC adjustment article which has been on the web for like close to 20 years.

Lou, thanks for help. Got all new cables and the tools, waiting for the arrival next week. Will update.

 

[radzikbjj@gmail.com]

So, I got the alignment tool. The boat is in the water, just a reminder, and it's King Cobra. I can't find anything on Kings, most of the info is just for Cobra.
How do I know if it's right, when the black tube slides back and forth? Do I have to pull it all the way out? - then it doesn't fit on the tool at all. Then I obviously have to slide it back in, so how do I know how much?
Does the bolt has to go flush against one side, tube hole into the pin and I rotate the barrel? The cable was freshly installed before I got the boat couple of months ago.

Second... I got the control cable as well. I will work on it as well. Right now it's hard to get it perfect - Rear goes in perfectly, forward grinds and then goes in. Then I adjust and it snaps into forward great, now problem with the rear. If I disconnect the control cable, put the throttle to forward, then by hand move the bracket into forward without much effort at all, and it seems like it snaps in perfectly, same with reverse, and neutral. Will be changing the top cable for sure. Another reason is that it looks identical to the carburator cable.