Lost port side transmission. Not a fun labor day

Zorba

Active Member
May 21, 2008
1,324
East Harbor, Lake Erie
Boat Info
2006 340 Sundancer
Engines
Twin 8.1 Mercruiser
I've been putting off writing this until I found out most of the details and what my course of action would be.

Over the labor day weekend we were headed out to the islands. As we came out of the channel and gave it throttle to get on plane, i had a serious vibration coming from my port side. Usually this is not a big deal, as many times seaweed fouls the gear and causes this. Normal protocol is to come off plane, and reverse to clear the running gear. This seemed to work as always so we proceeded on. As the 6 mile trip wore on i could feel a slight vibration but was not concerned. Before I headed into the marina we were staying at i jumped in the water just to see if anything was still under there. Nothing, so we headed in to marina to pump out and ultimately dock for the evening.

After pumping out, i reversed the port side engine to clear the dock and heard three very distinct and LOUD bangs, not internal bangs but something bouncing around in the ER bang. We were in a crowded marina so i immediately went to my dock. No transmission noise but as I maneuvered in to the dock a loud squeal started. I was close enough so i immediately shut down and coasted into the dock. I opened the ER to find this fiasco

trans_zps025fc120.jpg


3 of the 4 coupling bolts had actually sheared. In doing so the studs worked their way into the transmission case, turning my ER in to a machine shop...aluminum turnings and all. Big oh ****...

shearbolts_zps8158c774.jpg


At this time i had to weigh my options and decided to limp home on the starboard motor. (thanks Capt Bob F for helping me out. Next time i hope we run into each other under better circumstances.) Made it back to my home marina to asses what i could do. After talking with a mechanic on my doc, we decided to replace the coupling bolts and see if that was the cause of the vibration. The thought was one was loose, causing slight vibration, leading to a chain reaction. So i replaced the bolts and unfortunately same issue of vibration and wobbly shaft, and now transfluid leaking out the area where the bolts made contact. Sooo off to the service center.

On a side note the boat tracks amazingly well with one engine. I barely had to turn the wheel to keep her straight and she turned like normal. Reverse on the other hand is a different story. I'm glad i had plenty of folks at the dock to help

After telling the shop what was going on, they were convinced i had hit something and damaged the prop and shaft... Well we puled the boat and guess what, not even a ding on the prop, no shiny edges from getting into some sand, just nothing. I knew i had not hit anything but was secretly hoping i did just to have a prayer that i could cover this with insurance. No such luck.

I got the call from the shop yesterday that they think the trans just let go... They're not sure until they get it out and wont comment on it until they get a look internally, but i can only guess the carrier went out allowing the shaft to wallow around in there, vibrate, loosen the bolts and leave me where i am today.

Good news is i'll be back in the water by next Friday, so i can at least enjoy October at the lake. I'm going to head up this Saturday to pay the bill, which is not as bad as i had feared, so I will update then with more photos and what happened internally with the tranny then.

Sorry for the long winded post. If anyone has any thoughts as to why this could happen i'm all ears.
 
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I came in on one engine earlier in the year. A breaker had thrown, the one under the top plastic engine cover ( I think it was you that told me what it was).

Was surprised how well the boat tracked in open water, and actually through the Marina. Yep, the slip is interesting on 1.

Sorry for your problems, thank you for posting for others to learn from.
 
The high grade cap screws used in this application, when properly torqued, provide far more torque capacity than your engine and transmission can produce under normal operating conditions. Meaning, even at prolonged full throttle, these cap screws will not shear. The issue you have is one wherein the cap screws came loose, and the resulting carnage followed, as the nuts backed off, came into contact with the transmission case, and the whole assembly started chewing itself to death.

I don't like to speculate, but the most likely cause of this is a lack of proper torque application to the cap screws and nuts after a shaft alignment or other service that required loosening of the flange. It may have been a simple alignment, shaft replacement, engine and transmission install - doesn't matter. Whenever I am involved in a flange service, I make sure the transmission flange is absolutely clean, clean the shaft, clean the shaft flange, clean all the hardware, etc. Everything has to be clean so the mating surfaces come together properly. I then apply thread lubricant to the fasteners, tighten them down evenly by hand, and then torque to specification. These fasteners should also be inspected within a short time after any adjustment, and "eyeballed" periodically thereafter.

I'd be willing to bet you'll have a look at them every time you are in the ER after this incident. I am sorry this happened to you. Good luck with the repairs.

Dale
 
The high grade cap screws used in this application, when properly torqued, provide far more torque capacity than your engine and transmission can produce under normal operating conditions. Meaning, even at prolonged full throttle, these cap screws will not shear. The issue you have is one wherein the cap screws came loose, and the resulting carnage followed, as the nuts backed off, came into contact with the transmission case, and the whole assembly started chewing itself to death.

I don't like to speculate, but the most likely cause of this is a lack of proper torque application to the cap screws and nuts after a shaft alignment or other service that required loosening of the flange. It may have been a simple alignment, shaft replacement, engine and transmission install - doesn't matter. Whenever I am involved in a flange service, I make sure the transmission flange is absolutely clean, clean the shaft, clean the shaft flange, clean all the hardware, etc. Everything has to be clean so the mating surfaces come together properly. I then apply thread lubricant to the fasteners, tighten them down evenly by hand, and then torque to specification. These fasteners should also be inspected within a short time after any adjustment, and "eyeballed" periodically thereafter.

I'd be willing to bet you'll have a look at them every time you are in the ER after this incident. I am sorry this happened to you. Good luck with the repairs.

Dale

Thanks for the response Dale. So many thoughts are running through my head about this, and this is one of the exact scenarios that ran through my mind.

The bolts they are putting in will be wired on to prevent the nut from backing off. They are doing this to the starboard as well for piece of mind.

Carnage is an understatement. It was a bad day for sure. But in the end we made it home safe, the boat is being fixed, and another lesson learned...
 
Thanks for the post. I will be doing my end of season tranny oil changes, and will check my bolts.
 
Sorry to hear about this. Be sure to have the alignment checked after your in the water again. If you have never had the aligment done, that may have been a major contributing factor. Good luck
 
Wiring the bolts on won't fix the problem. Like Dale said, thread lock and proper torque. With wire they can still become loose. This is a more common problem than you might expect. I have several friends whose Sea Rays have experienced this.
 
Sorry for your trouble, but thanks for posting, gives me more things to keep up on. I will be checking these out the next time I’m at the dock.

Matt
 
Wow Alex, bumber. Hate to hear your having mech issues. Never fun... Best of luck and enjoy the rest of our season man.
 
Good news... New Trans is back in boat

Shaft and prop were in good shape so save a boat buck there. Will be back from the prop shop Wednesday and floating by Thursday.

Having the starboard check for alignment while I'm at it also replacing starboard coupler bolts with the wired style.

For any of you Lake Erie guys I highly recommend Lakeside yacht service and storage.
 
Glad you made it back safely Alex.. It's a shame this had to happen but at least you were close to your homeport ie you could have been on the Detroit River..I've Heard good things about the Lakeside Service Dept and will definately use them if the need arises.. It's nice that they got you back in the water so soon, we sould have several nice weekends left!!
 
Just to wrap this up. Final diagnosis was the carrier bearing failed letting everything wallow around inside the transmission case. One brand new shinny transmission later and i was back on the water over the weekend. The port side shaft was not bent and the props were out of pitch and cup so i had those adjusted. Not knowing any better before i never thought i had any vibrations, but with the adjusted props the boat runs as smooth as silk now and I've picked up a little speed.


I was a hard pill to swallow, especially since i take care of the boat religiously, but as the shop said, sometimes bad things happen for no good reason.
 
Alex, glad you got to enjoy the beautiful weekend... it sucks having boat issues I know all to well. Enjoy the rest of the season my friend!
 
"I was a hard pill to swallow, especially since i take care of the boat religiously, but as the shop said, sometimes bad things happen for no good reason."

+1 You can be as particular as possible in the ER but, mechanical things break. It is what it is. Glad you are "yachting" again.
 
This loss (IMO) should have been covered by your insurance. Who is your carrier?

Why do you think that. How would a mechanical failure on an 8 year old boat fall under insurance. I didn't even contact them once i pulled the boat and we scanned the props and shaft and found nothing wrong with them.
 
Why do you think that. How would a mechanical failure on an 8 year old boat fall under insurance. I didn't even contact them once i pulled the boat and we scanned the props and shaft and found nothing wrong with them.

From 2 angles- the professional one and the personal one.

Professional: an accident is a sudden, non-planned fortuitous event that causes a loss. Such losses are generally covered by yacht policies, as long as the failure is not due to an excluded item (such as wear and tear, neglect, etc- the exclusions as listed in the policy). Impact with an object does not have to occur to have coverage. You had an accident, and your policy should have been consulted for coverage. The good thing- most policies have a time period in which you can file a claim.

The above is predicated on you having a solid yacht policy, and not a policy from company that is tied into your home or auto policy.


Personal- September 2007, on my 2002 Trophy, the Bravo 3 outdrive had a serious mechanical failure. I have a close relationship with the local Sea Ray dealer (Lake Union Sea Ray), so the boat went there for diagnosis and repair. Travelers Insurance found that the damage was not impact related, and that there had been an internal mechanical failure in the lower unit.

Bottom line- $7k paid in repairs by Travelers.
 
Dealing with the exact issue on my 44 sundancer right now

Sorry to hear Doc. Hopefully they can sort something out, but from the other thread you started even with a new transmission I think they are way high.

Was definitely not fun but I was back in the water in a week.


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