88 Mercruiser engine coupling

roadrash

Seaman
Joined
Apr 3, 2007
Messages
58
My 88 Wellcraft 3.7 engine coupling blew this weekend. My buddy has the same boat and his blew last month. On his we could tell that the wood brace 4 the engine mount had saged over the years but mine seems fine. Now i know with a 20yr boat anything can happen but we both purchased these boats last year and are wondering if engine couplings are prone to go on these engines? Or mabie its the set up? Is there somthiong we should be aware of?
 

bomar76

Lieutenant Commander
Joined
Jun 27, 2002
Messages
1,963
Re: 88 Mercruiser engine coupling

Couplers are certain to be destroyed on any boat that hasn't had the alignment checked for who knows how long (most likely 20 years), and have obvious alignment issues such as rotten stringers.
 

HT32BSX115

Supreme Mariner
Joined
Dec 8, 2005
Messages
10,083
Re: 88 Mercruiser engine coupling

Yes this is true.

I had a boat that my dad bought new. I know he never replaced the coupler, never checked the alignment and never took it to any one else to check it either.

I had it a few years when the coupler finally went. (The aluminum splines looked like they were drilled out!

I got the boat in 1997 and the coupler lasted until 2003......My Dad bought the boat new........Oh....it was a 1966 Mark Twain..... 150 Mercruiser stern drive........Damn......The coupler only went 37 years!

I will agree with checking it frequently though. I'll pull mine every 2 years or so. Checking it frequently will allow you to lube the shaft, and do other "things" that you should do to the drive. A severe alignment problem will usually point to other problems like engine mount bolt(s) being loose, rotten engine mount wood, rotten transom, failed rear engine mounts and other things.





Cheers,


Rick






Couplers are certain to be destroyed on any boat that hasn't had the alignment checked for who knows how long (most likely 20 years), and have obvious alignment issues such as rotten stringers.
 

bomar76

Lieutenant Commander
Joined
Jun 27, 2002
Messages
1,963
Re: 88 Mercruiser engine coupling

The drive should be pulled EVERY YEAR to check alignment, coupler, ujoints, gimble bearing, grease splines, check bellows, etc.
 
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