Hit A Sandbar & Lost power

[Alpheus]

At 11 am this morning I was putting my boat in the water. At 11:15 I was dead in the water.

At 3 pm This is where I'm at.

I started out in the channel and when the no wake zone came I set the throttle to 2800 rpm when all of a sudden I lost power and the boat came to a stop. I immediatly put the boat in neutral and the engine never stalled. I put the outdrive up and tryed to reverse off the bar. I put the lever in reverse had the usual clunk gave a bit of gas and it just revved, no power. I put it in forward again with the usual clunk and gave it gas and again no power.

I shut off the engine and raised the drive to check the prop. The tips were missing some paint and a little scuffed up. I tried turning the prop by hand in forward gear and it was engaged. I started the engine back up and confirmed that the coupler and shaft were turning and circulating water. I put the the boat in forward and tried again and no power. I put it in reverse and the boat started moving. I drove in reverse all the way back to the dock. Just as I was getting there I tried going forward again and this time it engaged. I gave it some gas and the power was back.

I brought the boat home and started with the simple stuff. I checked the prop and the hub with no obviouse damage. I took it to my local prop shop and they torque tested the hub and confirmed it was good. I pulled drive off and checked everything with nothing found. I then pulled the engine to check the coupler with nothing found. I checked the gears in the top of the drive with nothing found. I have the oil draining from the drive now to pull it apart and keep looking for damage. No metal debris found in the oil and the drive makes no grinding when turning it by hand.

I took pics of everything:

Prop hub

Coupler

Splines Input shaft

Prop Shaft

 

[Alpheus]

Re: Hit A Sandbar & Lost power

Gears

As soon as I got home I started searching this forum and I checked everything that other people have mentioned when having a simular problem. I was sure it was the coupler, but it looks good to me.

My question is, what else should I be checking or am I missing something? I took detailed pics so if someone sees something Im not please chime in.

This is a 1994 Mercruiser Alpha One Gen II.

SN 0F233941

Thanks...

 

[airdvr1227]

Re: Hit A Sandbar & Lost power

You sure you didn't spin the hub on the prop?

 

[Alpheus]

Re: Hit A Sandbar & Lost power

You sure you didn't spin the hub on the prop?

Like I said I took the prop to a prop shop and they put it on a machine that torque tested the hub. It passed having never slipped. It acted like a hub went and I was hoping that that s what it was but nope.

 

[airdvr1227]

Re: Hit A Sandbar & Lost power

Sorry...I missed that part.

 

[Bondo]

Re: Hit A Sandbar & Lost power

Ayuh,... Split the Upper, 'n Lower,....
See if the top of the lower's vertical shaft is snapped at the o-ring groove....

 

[Alpheus]

Re: Hit A Sandbar & Lost power

See if the top of the lower's vertical shaft is snapped at the o-ring groove....

If this shaft is broken could it cause the problem to be intermittent?

As soon as I got the boat out of the water I put the drive in forward gear and spun the prop by hand and was able to turn the engine over a bit. I was just checking if the prop hub had spun.

I will have the case split in the morning. hopefully it will reveal something...

 

[Alpheus]

Re: Hit A Sandbar & Lost power

Split the upper and lower case and still no fault found.

Is it possible to put a borescope into the lower oil fill or through the top oil port and look at the gear mesh of the driveshaft and the prop shaft?

 

[a70eliminator]

Re: Hit A Sandbar & Lost power

Dang man no grass growing under your feet, your like a farmer with a stuck tractor lol.
Almost has to be the coupler, it cooled off and caught some resistance back.

 

[funk6294]

Re: Hit A Sandbar & Lost power

Can the prop shop troque check the coupler ???

 

[Alpheus]

Re: Hit A Sandbar & Lost power

Almost has to be the coupler, it cooled off and caught some resistance back.

I was almost positive that it was a bad coupler, thats why I waisted no time pulling the engine. I just want it fixed.

I cannot find any residue on the coupler, no burnt smell or no damage what so ever on it. Do the pics I took of the front and back side of the coupler not show if it was damaged or is can the damage be hidden inside?

I just wish after it broke it would just have stayed broke...

 

[a70eliminator]

Re: Hit A Sandbar & Lost power

Something seems awfull fishy, would think at least see some rubber fragments, maybe get a second opinion on that prop hub, look on the bright side, at least now you can detail engine bay. Did you smoke something..?

 

[Alpheus]

Re: Hit A Sandbar & Lost power

This prop shop is the best around.

http://www.murphyspropellers.com/

I watched them torque test it. The guy said that my prop with the square hub usually never spins, and if it does you can see the damage, but He checked it for me anyway and it passed.

I just called them about torque testing my coupler and they dont have a shaft that will fit. Im not just going to throw money at this and hope it goes away.

I'm gonna keep diggin'. Ill find it...

 

[Alpheus]

Re: Hit A Sandbar & Lost power

Just got back from having my coupler checked out and its fine. The tech at the marina showed me everything to look for. I then took over my outdrive to him and he checked it out. Nothing wrong with the outdrive. We came to the conclusion that I was stuck in the mud and thats why the boat would not move forward. I am going to put everything back together and take it back to the marina where the tech will put my boat on a dynamometer and go from there...

 

[njrextreme]

Re: Hit A Sandbar & Lost power

So you just tore down your complete powertrain over being stuck on the sandbar? lol I think I would have did some water tests first before going thru all that. Hope you find the issue if even you ever had one. Atleast you know everything is in good shape for future reff..

 

[airdvr1227]

Re: Hit A Sandbar & Lost power

So the theory is you were firmly stuck and what felt like to no power was just the fact that you were REALLY stuck. Sounds reasonable. Bet your glad that's all it was eh?

 

[njrextreme]

Re: Hit A Sandbar & Lost power

So how did you get unstuck? And did the boat run ok back to the dock? Or did you get towed in?

 

[Alpheus]

Re: Hit A Sandbar & Lost power

Well it had every symptom of a spun hub or coupler. Its just goofy how it happened. It would move in reverse but as soon as I put it in forward it would not move an inch. So once I got it going backwards, I just crept back to the dock in reverse not chancing losing the hub or coupler for good.

I dont mind tearing it down. I want to know if something was damaged and not take any chances. Plus I just learned alot more about my boat that will help me in repairs and troubleshooting in the future...