Repairing Coupling assembly

[Dominic123]

Hey guys just been told the coupling assembly has blown in my mercruiser 350 mag mpi
Have been told the Inboard engine will have to come out to change the whole assembly, can anyone verify this or advise from previous experience ?
Many thanks

 

[Bondo]

Hey guys just been told the coupling assembly has blown in my mercruiser 350 mag mpi
Have been told the Inboard engine will have to come out to change the whole assembly, can anyone verify this or advise from previous experience ?
Many thanks

Ayuh,..... Pull the drive, then the motor to change the coupler,...

That's how it's done,....

 

[Scott Danforth]

and since you have twins, pull both.

and then you must do the annual remove drive and inspect alignment and other PM's to prevent failure in the future.

 

[racerone]

Coupling assembly is on the flywheel.-----So yes , the engine must be pulled to get at it.-----BOAT = Bring on another thousand.

 

[Scott06]

would also be expecting to replace the drive shaft going into the coupler, inspect gimbal bearing ujoints and bellows while in there.
would verify alignment before you pull engine. Couplers usually last forever unless alignment is off.
It sounds worse than it is if you can lift the engine high enough / move forward enough to remove flywheel cover the engine doesnt fully have to come out. Good time to check rear motor mounts for collapse if alignment was off

 

[tank1949]

Hey guys just been told the coupling assembly has blown in my mercruiser 350 mag mpi
Have been told the Inboard engine will have to come out to change the whole assembly, can anyone verify this or advise from previous experience ?
Many thanks

Not 100% knowledgeable with MPI, only carbureted V8s, but to access coupler, drive and motor will have to be pulled. Who said coupler was bad and how did they prove it???? Perhaps u just spun a prop hub?

 

[Dominic123]

Not 100% knowledgeable with MPI, only carbureted V8s, but to access coupler, drive and motor will have to be pulled. Who said coupler was bad and how did they prove it???? Perhaps u just spun a prop hub?

Mechanic advised the coupler had blown due to corrosion apparently, just find it odd that the coupler had blown a day after the legs had been serviced.
One mechanic is telling me it’s coupler and the other one is telling me another answer. Either way will be coming out of the water but I just woukd like to know what I am up for

 

[Dominic123]

would also be expecting to replace the drive shaft going into the coupler, inspect gimbal bearing ujoints and bellows while in there.
would verify alignment before you pull engine. Couplers usually last forever unless alignment is off.
It sounds worse than it is if you can lift the engine high enough / move forward enough to remove flywheel cover the engine doesnt fully have to come out. Good time to check rear motor mounts for collapse if alignment was off

I may just do a overhaul if the engine does have to come out and replace the major parts.
I was just keen to know if the engine does have to completely come out to change coupler as my slip does not have the equipment to remove engines.

 

[Dominic123]

Ayuh,..... Pull the drive, then the motor to change the coupler,...

That's how it's done,....

Good to know champ, do you know how big of a job this is ? Would be first time pulling one of my boat engines out unfortunately

 

[Scott06]

Good to know champ, do you know how big of a job this is ? Would be first time pulling one of my boat engines out unfortunately

Depends on how much boat is around it. What is it in

 

[Scott Danforth]

I may just do a overhaul if the engine does have to come out and replace the major parts.
I was just keen to know if the engine does have to completely come out to change coupler as my slip does not have the equipment to remove engines.

That would be throwing good money away

A well maintained motor will run 5000 hours before it needs to be overhauled

 

[Scott Danforth]

Good to know champ, do you know how big of a job this is ? Would be first time pulling one of my boat engines out unfortunately

As indicated above. Depends on how much boat in the way. Could be a 20 minute job after pulling the drive, could be a 3-day ordeal if you have to remove the lazzenette and other boat bits

 

[kenny nunez]

First thing to do when the boat is on the trailer is remove the lower drain plug from the gearcase. It may be possible that the drive seized up from lack of oil which caused the coupling to fail. If that happened see if you do not have some fishing line wrapped around the propeller shaft that worked it self into the seals.

 

[racerone]

Service work at a big shop is expensive.-----BOAT stands for " bring on another thousand " and perhaps more.-----Owning a big , old boat is not cheap if you can not do the work yourself !