Engine coupler
 

I was out this weekend having a ball towing my son around on his new tube. I went to put the boat in gear to go home and nothing! No forward or reverse. Called Sea Tow, which I'm not a member, and payed 400 bucks to get towed back to the ramp. Now I'm gonna sign up for the 95 bucks a year to join! Oh well. But anyway the guy looked at the boat and said it was the coupler. I only have 200 hrs on this 98 260. To make matters worse I'm leaving on vacation in less than 2 weeks and we bring the boat! I remember I think Jan, had his replaced. Why did you do this? Is this a common thing? My mechanic said he'll have me back together in time, but you know how that can go. Anybody with input about this? How much should this cost? I was gonna do this myself, but I'd need the alignment tools to do it right. I'm sort of venting right now:(

Gary, I replaced mine due to the stbd motor mount locking tabs had never been bent down around the adjustment nut. Motor was almost sitting on the stringer. Replaced with the merc hi-po coupler(steel splines versus aluminum) and had a merc oil change kit installed since the motor was being pulled. only 209 hours on my boat.

COST-500 for coupler, 50 for quick change kit and 300 to pull motor.


JAN

Thanks for the reply Jan. I'm gonna check into the Hi Po also.He's quoting me 150-200 for the coupler, I'll have to double check, that sounds like a standard one. I don't want to do this every 200 hrs. My engine looks a little off sitting in the bilge, could be my imagination though. I took the back seat all apart so I should save some labor to get the motor out. That's a good idea for the quick change kit! Thanks!

I also removed my backseat to save on labor. $200 sounds a little to cheap, make sure it is not a used coupler. Best price I found on a standard coupler was from BAM at $365.60 list, and $311.94 discounted price.

Jan

Last week while I was @ Lake Cumberland, KY. A freinds 24' Cobalt 7.4 also spun his coupler. He has right at 500 hrs. I assume it is a sacrificial part and 500 hrs was not unreasonable. But 150-200 hrs sounds like serious misalignment.

My 02

I had a coupler go bad in my 97 260 at 50 hrs. It didn't let loose, but it vibrated a lot. The dealer took care of it. I sold the boat with 275 hrs last year and that was the only problem I had with it.

The couplers ONLY blow if your engine is out of alignment or you have a lot of HP and I mean a lot. They will never blow with a stock motor that is properly aligned.

I dropped the boat off this morning. He said he was gonna get the steel one not the aluminum. Brand new mercrusier coupler. We'll see how much it is, at this point I just want it fixed by July 3rd. Wish me luck. I'll keep you guys posted.

http://www.cpperformance.com/product...elines/141.asp

$289.95 USD

They will blow out if you are trimmed up way too high and gun it (like backing off the beach)
This has happened a few times (esp after a few boat sodas) to one of our members.
Beware.

Boat sodas? Me? Never:D I've never done that, but that is a good point. I did buy the boat used, so you never know how the other person treated it. That's just the nature of the hobby. And I would say it's safe to say these types of boats are used a little harder than a Searay. BOAT Break Out Another Thousand. There does seem to be a lot of bad Kharma this year though.

G-

Where did you take it finally ?

Wes

IF the engine is properly aligned you WILL NOT blow a coupling by excessive trim. It takes misalignment and torque to tear apart the rubber part of the coupling. The part that goes bad is the rubber not the splines. I have aligned many motors and one of the biggest things most people miss is that the rear mounts sag. You can get the tool to go in but the engine is not properly aligned. The universal joints will be constantly working instead of being in a straight line. A stock engine doesn't need the HP coupling. I am running 600 hp with two engines and the last boat had 638 hp and I have never blown a coupling with a properly aligned motor and I am using the stock one.

Tinker, please tell me a little more about alignment.........

For years, I have always done my own engine alignment and the tool has always inserted properly without any motor mount tweaking. Are you saying that this is not enough for proper alignment? What else should I be doing, looking for etc to ensure proper alignment.

For as many years as I have boated, I have yet to blow a coupler so it is either my boating habits or good alignment.

When the rear mounts sag you can still get the tool to go in but the angle is slightly off. With a stock motor this is not usually a problem. But if you add enough HP it will blow the coupling even though the tool says it is right. The angle is wrong and the universals are constantly putting sideways torque on the coupling. The coupling goes bad for the same reason that a under inflated tire goes bad. The under inflated tire gets hot from the sidewall flexing constantly. The same thing happens to the coupling- it is constantly flexing and then it goes out. If you have seen a coupling go out then you have seen the rubber goo that is created. I had this problem with my glastron. Three couplings in three weeks. spent a whole weekend figuring out what the reason was. Never blew another one after that. After the second one blew I took it to the dealership and all he did was use the same tool I had and said it was fine and charged me $75. That one blew the next day. Raised the rear mounts and locked them in place using washers and shims to make a solid rear mount. When the rear mounts start to go bad you will notice that the fiber washer will have crimp marks on it where it gets pinched.

Yup! I have to agree with tinker.

As long as the coupling is aligned with the bearing, the coupling will not fail for many years/hours. The drive shaft that connects them is straight and does not flex. That's the couplings job. However, excessive flex is bad. The coupling is actually a saftey. Instead of twisting up steel shafts and having metal flying around incase of a failure.

The only thing excessive trim does is put stress on the U joints. In the example Bill R gave, when trimmed extremely high like that, the drive lifts up, the U joints "bend" and the shaft that connects into the coupling and rides on the bearing actually slides back, away from the coupling, but stays strait.
That's why it's important to grease the splines on the shaft and the 3 O rings on it generously.

Every year I remove my drive when putting her away for the winter. I check my alignment then and again before I put it back on. Just cause. My boat was older so, once the boat "settled" I set the engine and it didn't move unless I did something.
On a new boat check the alignment after 20 hrs. I personally would check it often (a couple times a year) for the first couple of years. Until the boat "settles". Kinda like a new house.

DAVE

I got my boat back!:D The coupler was stripped big time! No teeth left. The front motor mounts were loose, I'll have to keep an eye on the mounts from now on! The price was 185 for the coupler and 5 hrs labor @ 85 bucks per.Plus 8.5%tax of course! Gotta love living in New York! I know, anywhere else would be cheaper on labor but that's what we pay to live here! He put a standard coupler back, because that is what it called for. I wanted the steel one but he talked me out of it. I'm just glad I'll have my boat back for my vacation, which I'm leaving on Friday after my son gets done with wrestling camp. Everybody have a great 4th and safe trouble free boating!