Coupler Failure

A

aneely

New Member
Sep 25, 2014
28
San Diego
Boat Info
1994 SeaRay 230 Sundancer
Engines
5.7 L Mercruiser Alpha 1
Any insight would be appreciated.

I recently purchased a used 1994 230DA and I'm just beside myself right now. After about the third short trip out on the boat the coupler failed on me. I just had the coupler replaced last month, a $$$$ job, and took the boat out yesterday for the second short trip since the repair was done and it failed again. My understanding is that a coupler is suppose to last for a very long time if properly maintained. Does anyone have any thoughts as to what could have caused me to go through two couplers in under 4 months? Is there something possibly a miss in the out-drive that could cause the failure? I'm definitely going to take it back to the guy who just replaced it and demand he make it right but I'm wondering if there is another underlying problem I should have someone else take a look at once I get it back again.

Thanks,
Andy
 
You need to see if the mechanic did an engine alignment after changing the coupler... very important!

Also was it properly greased? Mercruiser has a special "coupler grease" that they recommend.
 
Engine/Drive alignment can cause rapid wear of a coupler...but I'd have to imagine that was checked when it was replaced.
 
The alignment and proper greasing I would assume should be done properly by any mechanic, even a bad one, upon replacement. I'm just baffled that it could fail again with less then 4 hours of run time on the new coupler.
 
Make sure his alignment tool has splines while you are at it…The smooth alignment tool is not an exact fit….My guess is the engine mounts need adjusted. Even the wrong grease would last more than 4 months.
 
The coupler should be about $350+/- the R&R in my neck of the woods would be around $1200
 
Ash...it was a little over $1300 to have it first done back in December. Unfortunately, I'm pretty sure I'm stuck with having the same guy do it again unless I want to shell out another $1300. I'm just wondering once I get it back, again, if I shouldn't have another mechanic look things over. Aside from incorrect greasing or miss alignment is there anything else to have looked at before taking it out again? Bad U-joints, gimble bearing, anything like that cause rapid failure?
 
New engine coupler could have been crap from the get go…..Probably not going to be able to blame anything behind the transom because the gimbal bearing (which is self aligning) should keep it all lined up…Is there a new gimbal bearing on your original repair by chance? That should have been replaced too in my opinion. If it happened that fast look for a broken engine mount or loose nut on engine mount….

Taking it to another mechanic for a second opinion after repair would require removing the drive again…...
 
The gimbal bearing was not replaced on the original coupler job. Mechanic didn't recommend it and I didn't see the need for it as the boat, even though 20 years old, had less than 400 original hours on it when I bought it.

Feeling a bit like that Charlie Brown character walking around with a rain cloud following overhead. I want to be able to definitively identify why it failed so quickly after being replaced but I'm guessing that probably isn't going to be possible.
 
You should be able to find out why it prematurely failed...

Are you sure its what has failed this time?

I don't know if the Alpha drives have a cone clutch... I know the Bravo's do. Cone clutch symptoms are different.
 
I'm 99% sure. Once I remove the prop and double check the hub I'll remove any doubt but the way I was able to limp home yesterday has be pretty confident it's the coupler again. There is no cone clutch in the Alpha to my knowledge but I'm a newbie as I've only had this boat a little over 4 months
 
How/Why did the first one fail?
transom flex, rear motor mounts went bad, rotted front mount stringers.
If these symptoms were not corrected you can destroy a new coupler in as little as 20 hours.
 
Bt Doctur...I was never told why the original one failed. I assumed it was miss-aligned engine. I only wish the new one lasted 20 hours...it failed in less than 4 hours of operation which is why I'm so perplexed as to the cause.
 
If you don't find anything else causing this and replace the coupler for the 3rd time, do yourself a favour and check to see if the engine is shifting while under load. You'd need to have the engine hatch open and someone else at the helm while you closely watch the engine as the operator throttles up from idle (in gear). Determine if the engine is torquing over at all when load is applied. It may be something that will only be clearly evident while the drive train is stressed.
 
Are you sure it's the coupler? I thought I blew mine-turned out to be a spun prop.......
 
2nd SloBurn. I think would be about impossible to destroy a coupler that quick.

I would look at:

1. Spun hub on the prop.

2. The yoke shaft on the drive. What happens to the coupler is due to engine mis-alignment and or lake of grease the yoke shaft wears the grooves on the coupler. You can tell this by looking at the yoke shaft, instead of nice sharp groves, they are rounded. You might have needed not only the coupler, but a new yoke shaft also.

3. If the engine were out of alignment bad enough to cause damage to the coupler in 4hrs, your mechanic would not have been able to install the drive. The gimbal bearing has to be in approximate alignment to even install the drive.


Good luck, I really don't think you have spun another coupler,
 
Hi, I'm knew to the sea ray forum, so I can not know if what I'm about to say has already been said. The Coupler bolts onto the back of the engine "like a flywheel" actually acts more like a propeller hub cause of the rubber between the part that mounts on the engine crank and the splines that the outdrive penetrate. There will be a Gimbal Bearing mounted to the transom, which stops the outdrive drive shaft from floping around between the drive and engine. The out drive bolts onto the back "aft side" of the transom. The shaft "with universal joint" goes through the Gimbal bearing "which keeps it in alignment" and penetrates "the splines align with those in the back of the Coupler". With all that said, there are a lot of things to go wrong, but telling me the Coupler has failed a second time makes me think heat or engine alignment might be a problem. My advise is to watch some u tube videos. This repair calls for the removal of the outdrive and dis-assembly of the after part/bell housing on the engine. I would at the very least pick up and slide the engine forward or more likely pull the engine and work on it in my garage. Than I would inspect motor mounts and cooling, not to mention replace belts or anything else that might be hard to touch while installed on the boat. replacing the Coupler and or Gimbal bearing are pretty easy if your taking your time. The hardest thing will be re-aligning the engine to the gimbal bearing. and again U Tube can walk you through this process. You know something caused the problem, it could be anything. So take your time even if your using a good mechanic follow my advice and make sure all of the above happens and she will be fixed once your done. Big problem with a job like this is scope creep. you could find yourself replacing a lot of stuff. My advice if it looks iffy replace it and if it isn't broke don't fix it.
 
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Warning to sensitive readers: This is a rant about molson9's post.

Seriously? How is most of what you wrote here helpful? The OP is not a mechanic or a DIY'er, otherwise he would not be discussing the necessity of returning once again to the mechanic for repair/replacement. Do you really think suggesting he move the engine around or pull it out and put it in his garage is going to help him. Come on...get real. When was the last time YOU lifted an engine out of a Sundancer with a cherry picker in your driveway? You haven't, because it takes a crane gantry to do it.
molson9 said:
Hi, I'm knew to the sea ray forum, so I can not know if what I'm about to say has already been said. (Yes you can, read the thread carefully and research other similar thread topics!) The Coupler bolts onto the back of the engine "like a flywheel" (The coupler bolts to the flywheel, not the back of the engine) actually acts more like a propeller hub (No it does not...that is not the function of the rubber in a coupler) cause of the rubber between the part that mounts on the engine crank (wrong again) and the splines that the outdrive penetrate. There will be a Gimbal Bearing mounted to the transom, which stops the outdrive drive shaft from floping around between the drive and engine. (Your understanding of the mechanics of a drive system are severely limited. A gimbal bearing does not exist to prevent a shaft from "flopping around".) The out drive bolts onto the back "aft side" of the transom. (Do you actually believe that the OP or any of us did not know that the outdrive is bolted to the "aft side" of the transom?) The shaft "with universal joint" goes through the Gimbal bearing "which keeps it in alignment" and penetrates "the splines align with those in the back of the Coupler". With all that said, there are a lot of things to go wrong, but telling me the Coupler has failed a second time makes me think heat (Really? From where? Explain how the coupler could "heat up" enough to cause failure.) or engine alignment might be a problem. My advise is to watch some u tube videos. (Your advice to watch videos is utterly useless, unless you can provide a link to a specific video that addresses his EXACT problem, of which you don't even have a clue how to diagnose; and that the video repair is being performed by a certified professional.) This repair calls for the removal of the outdrive and dis-assembly of the after part/bell housing on the engine. (Again, really? The "after part"? Would you please show me a Mercruiser diagram listing the "after part" and what its function is? Do you actually think the OP does not realize the extent of work that is required to replace a coupler? He has already paid to have it done once before. He knows that many hours of labor and parts removal are required.) I would at the very least pick up and slide the engine forward or more likely pull the engine and work on it in my garage. Than I would inspect motor mounts and cooling, (Please tell us why you would inspect the "cooling". I am anxious to know if the "cooling" on my boat will destroy my coupler soon!) not to mention replace belts or anything else that might be hard to touch while installed on the boat. replacing the Coupler and or Gimbal bearing are pretty easy if your taking your time. (Hmm, you have done this procedure yourself many times? Since you stated that the coupler bolts to the back of the engine, or the "crank", you have indicated to all of us who have first hand WORKING knowledge of engines, that you indeed, have not replaced any couplers.) The hardest thing will be re-aligning the engine to the gimbal bearing. (So you are telling the OP and thousands of people on this forum that aligning a gimbal bearing is more difficult than the removal and re-installation of an engine and drive system on a boat?) and again U Tube can walk you through this process. You know something caused the problem, it could be anything. (Huh? Are you for real?) So take your time even if your using a good mechanic follow my advice and make sure all of the above happens and she will be fixed once your done. (I recommend that the OP DOES NOT follow your advice. You have no idea what nonsense you are spewing.) Big problem with a job like this is scope creep. you could find yourself replacing a lot of stuff. My advice if it looks iffy replace it and if it isn't broke don't fix it.
Click to expand...
("If it isn't broke, don't fix it"...Thank you Captain Obvious!)

To all CSR members/moderators...my advanced apology to those I may have offended with my response to this poster. I cannot in good conscience read such drivel without applying corrections or rebuttals to obviously flawed statements and downright ignorant advice and suggestions.

Rant over.
 
you call attacking someone you don't know a rant? you think picking apart someones post is just a rant? Like i said I'm new around here. I don't have a clue what equipment he has available I thought this was an open forum. After reviewing your Rant I come to the conclusion that you have never done this before. The alignment requires you to adjust the motor mounts up and down until the alignment shaft does not bind. Just about every time I've done this I have found problems with ether the engine mounts or if equipped bell housing mounts being out of alignment. The poster has a small boat (trailerable) so he might have some equipment available to him. The fellow was asking how to fix a problem and I answered with advise I would have shared with anybody Now with that said who the hell are you to question if the poster has the ability to fix his problem no matter what it takes? I have done this in boats, garages and on piers. Have you? why would you sensor someone who is only trying to help someone else fix a problem? makes me think I should look at your posts to see if you have a pattern of heckling new posters. I help people successfully fix there boats all the time, do you? I plan on staying on this site, perhaps you should skip my posts if they offend you.
 
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