ESA knock???

[LAC_STS]

My boat has been running great. Sometimes when i shift into F the esa will stock and i have to jiggle the handle to get it to stop stumbling

Well, I changed the impeller and put a new SS Apollo prop on yes. Today I took it out today and notice that the boat now makes a weird almost knocking sound when the ESA stumbles the engine. It doesn't do it if I press the ESA arm manually at the engine but when I shift it makes the noise.

I love the new prop but today when I took it out it was vibrating from 1400-3200 rpms. It didn't use to do this before. I checked and the new prop is on there and tight and doesn't have any play. Nothing else has been changed on the boat engine besides the prop and impeller.



Here is a video of the ESA sound/knock.

http://www.youtube.com/watch?v=p6hAwGFVHF4

Anyone know what the knocking when the ESA is about?

And what could cause this vibration? I assume it has to be related to the prop because it's the only thing that has changed besides a new impeller.


Thanks

 

[LAC_STS]

Re: ESA knock???

Sorry thought I posted the link from my Iphone but I guess it didnt work.

Here ya go.

http://www.youtube.com/watch?v=p6hAwGFVHF4

You can hear that I press the ESA rocker arm twice at the engine and then I walk to the helm and shift it into F twice. This is all tied up snug to the dock.


Thanks

 

[HT32BSX115]

Re: ESA knock???

Howdy,


You have a shift cable/shift plate adjustment problem and/or a problem with the microswitches that control the ESA.

The ESA should ONLY activate when you have "out-of-gear" pressure on the lower shift cable and actuation linkage.

That should only happen when the shift dogs are loaded (I.E. in gear, IN the water)

It should be momentary and only while the engine is coming out of gear. The esa deactivates right when the drive comes out of gear.

It should not activate when going into gear.

If you do not have an OEM OMC service manual for your year model engine and drive and you want to work on it yourself, now would be a good time to get one.

Also take a look at the following. http://www.hastings.org/~stuart/cobra/


Cheers,


Rick

 

[LAC_STS]

Re: ESA knock???

Thanks. Not trying to argue but I though it was supposed to stumble going into gear also. I know i have a problem where it sometimes when I put it into gear it won't stop stumbling unless I giggle the control. But until today (after I out the new prop and new impeller on yes) it would not make that noise when stumbling.

I have an oem omc manual, have read the Hastings site and tried adjusting it. I can get it pretty close but every now and then it still stumbles.

But my question is what is that noise? It has never made that noise before while stumbling.

 

[HT32BSX115]

Re: ESA knock???

"Stumbling" going into gear is an indication of the lower shift cable binding and/or linkage/shift dogs binding internally.

If you think about it, the ESA is there to interrupt or briefly reduce the torque on the shift dogs sufficiently to allow you to separate them. (they're undercut so they literally hold themselves together. Even when you're at idle, there's considerable force on them so it takes a lot of either "push" or "pull" force on the lower shift cable to get them apart.

If you were above idle, you probably couldn't pull(or push) them apart at all....and if you tried, you would either bend the cable(pushing) or break something(pulling).


When you put it in gear, there should not be a lot of force required and there's no benefit activating the ESA other than to lower the RPM slightly.

That's really not required if the RPM is low enough already. Dog Clutches last longer if you engage them at low RPM.

My former 460 idled at around 550 RPM and it went into gear pretty nicely. The force on the lower shift cable was never enough to move the shift actuator (#37 below) when going into gear.....

Only when you're coming out of gear should the shift actuator move (notice how the cable from the shifter is slightly offset from the shift actuator......a small force on it doesn't move the actuator where more force does. Going into gear should NOT take enough pressure to move it.....and subsequently activate the ESA))

I have an oem omc manual, have read the Hastings site and tried adjusting it. I can get it pretty close but every now and then it still stumbles.

Again, If it's still stumbling when going into gear, you either have binding in the cable (corrosion, bent, etc) or something in the drive is binding.....

You should probably replace the cable if it's binding.

To determine if it's the cable, remove the drive and see how easily (or hard) the lower shift cable is moving.... It should never move the actuator with the drive removed ......

When everything is working correctly, It should go into gear very easily.


That clunking/knocking sound when you shift into gear sounds a LOT like it's not going all the way into gear further indicating you NEED to check/replace your lower shift cable and/or determine why it's binding going into gear......

 

[LAC_STS]

Re: ESA knock???

Ok.

Any idea what the noise is?

It has never made that noise before.

 

[HT32BSX115]

Re: ESA knock???

Ok.

Any idea what the noise is?

It has never made that noise before.

It looks like I added this to my last post while you did your last one....

That clunking/knocking sound when you shift into gear sounds a LOT like it's not going all the way into gear further indicating you NEED to check/replace your lower shift cable and/or determine why it's binding going into gear...... _

 

[LAC_STS]

Re: ESA knock???

Thanks for all info.


I just remembered that Friday afternoon when I went and changed the impeller and prop I put the boat in F gear and forgot to put it back into N when I was done.

Sat I told the marina to put the boat in the water and when I got there it was still in F gear.

Could leaving it in F gear overnight (engine off) caused the cable to stretch and that's what I'm getting this noise now?

And do you think a bad shift cable could cause a vibration like I describe?


Thanks again

 

[HT32BSX115]

Re: ESA knock???

Could leaving it in F gear overnight (engine off) caused the cable to stretch and that's what I'm getting this noise now?

No. Because once it's in gear there's little or no actual force on the cable.

Have you ever had the cable replaced?

Water intrusion into the cable usually causes corrosion internally. (it's a steel cable) The corrosion then causes it to bind. With a "good" cable, It should take very little force to move it.

When you move the shift actuator in the drive (by hand) it should also move fairly easy. Once in FWD, or REV, there's no force required to keep it in that position (that's the reason for having shift dogs!!).

If the cable becomes sticky (due to corrosion, stretched jacket, etc)placing the shifter in the gear may not completely place the drive in gear.

This may cause the dogs to NOT engage completely. This eventually damages them (permanently)......then drive must then be disassembled and repaired/rebuilt etc.

I doubt a sticky shift cable (and subsequent damage) would cause any vibration. If it didn't shake with the "old prop" I would suspect the "new" prop.

If you changed the prop because you whacked it on something, I would suspect a bent prop shaft.

 

[LAC_STS]

Re: ESA knock???

I just bought the boat in June. I got a bunch or receipts from a marina that the PO was taking it to.

On one of the receipts is a drive shift cable and installation. The cable is a red one and does look new. I checked where the shift cable bellow is and didnt see any water getting in there but I guess its possible.

I changed props because the old one is a pretty old 15P alum one and I wanted a SS and had enough RPMs to go to a 17P.

I got all the correct hardware now to put the old alum prop back on so I'm gonna go down to the boat and try that and see what happens.


I just dont get how it was shifting great had no vibration problems, then I put the boat up for 3 days, change the impeller and prop and now I have these problems.

I know the vibrations could be caused by the prop so I'm gonna try that first.

Ill report back.


Thanks

 

[HT32BSX115]

Re: ESA knock???

I cannot "feel" your vibrations (although I feel your pain!!)

So I can't diagnose them......they're usually prop related since that's the thing that is exposed, turns fast and has a LOT of mass...........


Other things could include ignition, burnt valve, timing, vacuum leak....the list goes on....

Is it possible that "they" dinged your prop moving the boat around? it doesn't take a lot to throw one out of balance.....

On one of the receipts is a drive shift cable and installation. The cable is a red one and does look new

... that doesn't always mean that it actually happened though......

I wouldn't rule it out.


To determine how good the cable works, you'll have to pull the drive and see how easy it is to move the cable and actuator.

SOMETHING IS BINDING...... and causing the ESA actuator to move when it shouldn't.

Be sure you check the alignment prior to re-installing the drive.

 

[LAC_STS]

Re: ESA knock???

Ok so I'm at the boat and I put the old alum prop on and took it out and no vibrations and no noise going into gear.

It actually doesn't activate the ESA going into gear if I shift it pretty quick. But if I shift into gear slowly it activates it.

But either way I switched between the new SS prop and the old alum prop three times and everytime was the same thing.

With the SS prop on the engine makes that noise when the ESA is activated and the whole boat vibrates pretty bad through the rpm range.

With the alum on it doesn't make the noise when the ESA activates and it does not vibrate at all.

I looked the SS prop over and it looks brand new. There isn't one ding or imperfection on it.

So the prop must be out of balance right?

 

[HT32BSX115]

Re: ESA knock???

It may be out of balance.

Hard to say. I have a really hard time believing that a prop can affect going into and out of gear.

You might drop it by a prop shop. and have them check balance etc.....

It actually doesn't activate the ESA going into gear if I shift it pretty quick. But if I shift into gear slowly it activates it.

You should NEVER shift a Cobra slowly into or out of gear (especially INTO gear)


I just sent you a PM by the way.

 

[LAC_STS]

Re: ESA knock???

I know I know. I think I need a new control box or something because sometimes it's a PITA.

I can't see how I would affect shifting either but I tried it three times and each time with the SS prop on it made the knocking noise when the ESA was on and with the alum on it didn't.

This os my first time having an interchangeable hub and it looks simple but I wonder if there is something I'm missing?

Thank you so much for your help. It's greatly appreciated.

 

[HT32BSX115]

Re: ESA knock???

I never used props with removable hubs. ....Yours is new? I wonder if the hub is defective/damaged. It should be an easy swap. Those hubs are not all that expensive are they?

The 17 and 19p SS props I have are the original type OMC props that fit all the Cobras, big Evinrude and Johnson outboards.

I probably would have went to the interchangeable type props if I had kept the Cobra.

I wonder if you have the wrong hub? I don't see how in the world a different prop could affect shifting.

 

[LAC_STS]

Re: ESA knock???

Yes hub is new, prop is new.

Yes the hub kits are pretty cheap. About $30-35

I'm pretty sure it's the right hub. It only gives two options for hubs for an omc sterndrive. Pre 1990 and after 1990. I have the Pre 1990 one.


I'm gonna call tom and check, and check about the prop.

 

[HT32BSX115]

Re: ESA knock???

Yeah. If there's anything wrong with it, I'm sure they'll make it good....

 

[wire2]

Re: ESA knock???

A stainless prop is ~ 3 times the weight of a comparable aluminum prop. That gives a boost of flywheel effect, but your drive should be able to handle it easily.
Have someone operate the shifter at the helm while you watch the switch activation, try to see what the difference is. I'm thinking the helm may just barely make the switch, then the stumbling engine causes enough vibration to make/break the switch several times a second.

 

[LAC_STS]

Re: ESA knock???

What is flywheel effect?

I had a SS Ballistic on there and there was no vibration. It was heavier than the alum one but the blades on it were pretty thin so the Apollo is still heavier.

 

[LAC_STS]

Re: ESA knock???

So, I just got off the phone with the place I bought the prop from and they said to send it back to them and they will check it. They said if it is out of balance they will fix the prop and if they cant fix it they will replace it.

They also said I have to pay for shipping and if they find it is out of balance they will credit the shipping to me.

Is this BS? Should I accept a "fixed" prop? Shouldnt I get a new one?