Gary C

Boat sodas? Me? Never 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.

WesSmith

G-

Where did you take it finally ?

Wes

Tinkerer

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.

hp500efi

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.

Tinkerer

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.

Dave F

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

Gary C

I got my boat back! 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!