OMC 460 problems

[kevlh21]

I bought a 1989 bayliner 2755 with 460 king cobra. Engine will start up good and run for a couple of minutes but stall out. There are two wires that im not sure where it goes. Ive searched and searched but cant find out where they go. Can anyone help me? Here are some pics of the wires and sensors. Thanks!
Here is the first wire connected to the harness

The second wire is connected to 2 sensors

 

[mthieme]

Re: OMC 460 problems

What color(s) are the wires and are they common to a single plug?

 

[kevlh21]

Re: OMC 460 problems

The engine only runs for a couple of minutes if the wire is connected or disconnected. I believe it is temp sensors but the engine wont run long enough to warm up

 

[newport dave]

Re: OMC 460 problems

I believe the wires your talkng about would connect to the ESA (Electronic Shift Assist) module, which appears to be missing on your engine. The shift interrupt switch may have been wired directly to the coil rather than through the ESA module, which is not too uncommon. It may not have anything to do with the stalling issue, which sounds fuel related to me.

 

[kevlh21]

Re: OMC 460 problems

I'm new to boats what exactly does it ESA do?

 

[chiefalen]

Re: OMC 460 problems

The electronic shift assist module cuts down the rpm so you can shift into and out of gear smoothly.

Due to the way the clutch dog is shaped omc found it in there infinate wisdom to include that module into the harness.

 

[mthieme]

Re: OMC 460 problems

Tan wires go to oil and temp senders which you have pictured. n These should not go into the main harness (I believe).
The ESA module should have four wires total connected to it, 2 purple which come out to a connector, one black which is a ground and one blue which goes to another connector.
This should not have anything to do with your problem though.
I agree with Dave, I'd check the fuel system out.
Have you done anything else yet?

 

[kevlh21]

Re: OMC 460 problems

Here are some pics of the motor.

 

[chiefalen]

Re: OMC 460 problems

The other plug that is in the holder that looks like the one in the pic not connected did you try unplugging that one.

Thats the over stroke switch.

Will it run with both disconnected.

 

[kevlh21]

Re: OMC 460 problems

The boat hasnt seen water in over 5 years so I was making sure that wasnt affecting anything. I just need to clean the carb. All my gauges work on the insturment cluster, it shifts into forward and reverse good and everything seems to be fine (except the stalling part)

 

[kevlh21]

Re: OMC 460 problems

The two sensors are connected together and are on opposite sides of the engine. One is under that harness and the other is by the distributor.

 

[HT32BSX115]

Re: OMC 460 problems

It looks like the ESA was removed? I couldn't see it in those pictures. The ESA "pulses" the ignition when you come out of gear. (which then pulses the torque on the shift "dogs")

( I wish I had seen this earlier. I just sold my old ESA, bracket etc.... along with a whole bunch of other stuff......)

you really shouldn't try to run it without an ESA (if it is indeed gone) it will be VERY hard to get out of gear and will eventually screw up the lower shift cable.

Do you have a service manual?



(EDIT: Actually I think I see the ESA under the main fuses on the shift plate)

It may be defective....

 

[mthieme]

Re: OMC 460 problems

I don't see a water separator anywhere, but I believe the xx55's have a lot of accoutraments to either side. You might wanna change that of course. I assume there is a fuel valve nearer to the tank (?) that is on.
I hate Holley's, there finicky. Good luck there.

One year decided we couldn't live without a comfortable overnighter. Although not a Bayliner fan, I fell in love with the 2855. It has a nice interior layout - roomy head, everything but AC. I looked at 6 different boats. Every single one had the 460 and every single one needed manifolds.
As a result, I wound up with a 14' skiff which my wife is scared of (too small) and sleep in my own bed!

 

[HT32BSX115]

Re: OMC 460 problems

The water separator is usually in front on the port side of the engine (underneath the alternator) The fuel pump is under there too........the oil filter is the one with the ss braided lines.....

 

[HT32BSX115]

Re: OMC 460 problems

I'm new to boats

By the way,

I will apologize right now for the beating you're going to get from some
for buying a boat with a 460 King Cobra in it.

But the fact of the matter is you didn't know, but still made a BIG mistake.

Now, thats out of the way.



You NEED to start looking now for another big block engine and drive (Mercruiser or Volvo Penta) So you can swap it out at some later date.

Your best bet would be to find a damaged boat with either a VP Duo-prop or a Merc Bravo III (A boat that big NEEDS a duo-prop type drive and a big block engine.)

You'll swap EVERYTHING. The transom cutout is the same. (drill two additional bolt holes)

Don't put a LOT of money in that 460/Cobra.


Sorry about that!:redface:



Rick

 

[chiefalen]

Re: OMC 460 problems

You running it or trying to run it from the onboard gas tank?

If it were my motor i would clean all the filters, one in the fitting at the carb, one in the fuel pump if there is one there, and the fuel water separator filter changed.

Rebuild the carb.

Than i would run it on a external tank of gas till i get it running good.

Of course you did check all the wires and under the dizzy cap.

And the neg ground clean it good all the connection need to be cleaned i bet.

You got good clean cables on the battery? Good tight connection to the battery.

Plugs good, wires good?

The kill switch is good not maybe vibrating and shutting down the motor is it, disconnect the wires to it till after the motor is running good.

 

[a70eliminator]

Re: OMC 460 problems

Are you seeing any oil pressure at the gauge? I'm asking because I see your oil pressure sender and there appears to be another switch Tee'ed off of it, I see it as a low oil pressure interupt switch? you really need the OMC service manual.

 

[kevlh21]

Re: OMC 460 problems

I know where the water seperator is it is below the oil filter. I do need to change that out. I cannot find any other wires that arent hooked up to anything for the life of me. Those two wires are the only wires not hooked to anything. I bought the boat with a broken outdrive. It has a king cobra motor with a cobra outdrive whats up with that???? is that normal? anyways I rebuilt it and now trying to get everything running smoothly.

 

[chiefalen]

Re: OMC 460 problems

When you rebuilt the drive you count the teeth on the gears ?

 

[HT32BSX115]

Re: OMC 460 problems

I bought a 1989 bayliner 2755 with 460 king cobra. Engine will start up good and run for a couple of minutes but stall out. There are two wires that im not sure where it goes. Ive searched and searched but cant find out where they go. Can anyone help me? Here are some pics of the wires and sensors. Thanks!

Back to your original problem. If the engine runs for a "couple of min" it's probably NOT ignition related.

Look to the fuel filter, carb, anti-siphon valve and/or fuel screen in the tank.

you can get a jump on it by doing what was suggested above. Disconnect the fuel line to the carb and connect a line directly to an external fuel source. Then troubleshoot your fuel source.


btw,

You can get a rebuild kit for your carb from Napa. Mine was about $75 or so. (I still have the carb....if you want it, PM me.) It's very easy to rebuild that Holley.

Regards,


Rick