Bravo 3 coupler? WILL NOT ENGAGE

[the man]

I have a 2004 Mercruiser 5.0 SN OW003759 with Bravo 3 SN OW108118. The coupler has gone out once before requiring an engine pull to replace. Now I have the same symptoms again- will not engage in forward or reverse, cables are free too move and appear to be fine and have full range of motion, and there is a intermitent clicking / minor scraping sound that increases when I try to put it in gear.

First question: Any other ideas? Besides the coupler...
Second question: I have this set up serviced annually including alignment, if this is the coupler again why is this happening? On both occasions this happened just after a long (20 minute) no-wake zone.

Thanks

 

[the man]

Re: Bravo 3 coupler? WILL NOT ENGAGE

the bravo 3 has counter rotating props. I assume if I grab the props and try to spin them that they should be linked and counter rotate with a positive conection- unless they are spun. also, this noise when in neutral would not come from spun props.

 

[Don S]

Re: Bravo 3 coupler? WILL NOT ENGAGE

I'm not even sure the B3 props have hubs that could be spun. I think they are solid. Even if they were hubbed, the chances of both props going at the same time is next to impossible.
If you look behind the engine where the shaft from the drive enters the coupler, do you see a lot of metal shavings? if not, it may not be the coupler. IF you can't get back there to see, a digital camera will help.
While the cables will move freely, are they actually moving the shift linkage in the drive?
IF it is the coupler, did they put any grease on the splines? Usually coupler splines being worn/ripped out is due to lack of lubrication.

 

[Bondo]

Re: Bravo 3 coupler? WILL NOT ENGAGE

IF it is the coupler, did they put any grease on the splines? Usually coupler splines being worn/ripped out is due to lack of lubrication.

Ayuh,... And it's the Worst at trolling/ idling speeds...
The splines are Constantly loading,+ Unloading, grinding themselves to Dust...

 

[HT32BSX115]

Re: Bravo 3 coupler? WILL NOT ENGAGE

I'm not even sure the B3 props have hubs that could be spun. I think they are solid.

That is true. If you had "spun" BIII props, the blades would be unrecognizable!!

I would vote for the something going on in the shifting mechanism if the coupler hasn't failed......(and just because it's new doesn't mean it hasn't failed too.....)



Regards,


Rick

 

[Fun Times]

Re: Bravo 3 coupler? WILL NOT ENGAGE

I'm not even sure the B3 props have hubs that could be spun. I think they are solid.

Your right Don, they are like solid hubs.

To The Man.
By using your engine serial number I was able to do some home work for you And there is a chance I may have found a reason for the problem your having, That is as long as the problem turns out to be your engine coupler.

If the problem is another engine coupler then there could be a few reasons why it went out again.

One of the reasons could be because you are pushing a big heavy 25.6 ft boat that is Approximately (w/Std Engine) 6,300 lbs+ with a small engine, that according to the engine hours at the time of your last engine coupler change That Mercruiser did for you when you where just out of warranty.
And by the looks of it, you really like to use your boat a lot.

I'm curious as to how many hours do you have on your boat right now?
Are you keeping up with your drive services? (Greasing the coupler and checking the engine alignment). oops, Scratch that, I see you do.

Also like Bondo said slow speeds are harder on the couplers when you are pushing that much weight, And it sounds like you do a lot of slow boating?

So to help you over come with some of these issues with your next engine coupler, you will want to consider buying an upgraded style engine coupler, For a little bit more money of course. Here are the two styles Mercruiser has to offer.

The first coupler is going to be their standard one, Part number (861523A9) COUPLER ASSEMBLY, Engine - Short Aluminum Hub (Bravo and All Jackshaft Models). MSRP:$509.92

This next coupler is considered their workhorse, Part number (861523A11) (option) COUPLER ASSEMBLY, Engine (Bravo)(Steel Hub For Work Application).MSRP:$653.50

Just so that you are aware, the last coupler that was installed in your boat was the standard one, Part number (861523A9)

So the upgraded style engine coupler may fit your needs just a little bit better for your situation.

I hope this helps, Good luck with it.

 

[TilliamWe]

Re: Bravo 3 coupler? WILL NOT ENGAGE

Your right Don, they are solid hubs.

Bravo 3 props actually are two pieces. However, as HT states, if you spun one you wouldn't be able to recognize the outer part as a prop. The outer part is welded solid to the "inner" to the point where they are really like one huge piece of stainless steel.

If it turns out to be the coupler again, then the engine mounts are either installed wrong, or the the transom is rotten and flexing, or the stringers are rotten. Something that would allow the drive to be "aligned" once a year, but that also aloows it to move under a load.

 

[the man]

Re: Bravo 3 coupler? WILL NOT ENGAGE

Your right Don, they are like solid hubs.

To The Man.
By using your engine serial number I was able to do some home work for you And there is a chance I may have found a reason for the problem your having, That is as long as the problem turns out to be your engine coupler.

...

So the upgraded style engine coupler may fit your needs just a little bit better for your situation.

I hope this helps, Good luck with it.

How the heck do you know all this? I really appreciate the help! But is big brother watching me? I have had work done at three different shops, and one of them is out of business now. I think the boat has 450 hours on it now- it is 10 miles away so I am not sure.

Anyway, besides being Orwellian, this is a big help. I pulled the outdrive & yes, it was the coupler. I am going to do the work myself- not as much to save money as for the learning curve. I will be looking for the correct manuals, and of course will most likely be back here often for advice. And I will use that coupler as suggested- that is the kind of stuff that makes this resource invaluable.

Thank you again. Any help with correct manuals to download would be appreciated. Plus I need to figure out how to align and all that.

 

[the man]

Re: Bravo 3 coupler? WILL NOT ENGAGE

If it turns out to be the coupler again, then the engine mounts are either installed wrong, or the the transom is rotten and flexing, or the stringers are rotten. Something that would allow the drive to be "aligned" once a year, but that also aloows it to move under a load.

Boat is in excellent shape, no rot and kept indoors /heated / dehumidified when not in the water.

A "friend" of mine banged up one of the props last fall- although he paid to have the props re-done he may have damaged the coupler?

As far as alignment, a "boat mechanic" told me today that if it is not aligned correctly, you cannot install the outdrive shaft. And he told me that it cannot be out of alignment if the shaft is in there. Now I am a newbie to actually performing this type of maintenance (as opposed to just paying for it), but that cannot be true- why would we check alignment every year if this was the case? Maybe someone could clarify this?

That is another reason I am going to start doing all this myself- I never know who to believe so I need to learn first hand.

 

[Don S]

Re: Bravo 3 coupler? WILL NOT ENGAGE

Head up to the adults only sticky (first thread in this forum)
Find the manual downloads. You need #31, 36, and 37 for the engine, along with manual #28 for your drive and transom shield.