Sea Ray with MerCruiser MCM 4.3LX coupler temperature

[Lansselot]

Hello,
We burnt out the rubber of our engine coupler. Don't now why, checkt the alignment at the start of the season with my self made alignment tool and this looked oke. I now bought a real alignment tool to be sure.

Pulled the engine, replaced the coupler, front engine mount and rear engine mounting hardware.
Engine alignment was harder than I hoped to get it right, I'm planning to have our work checked by a professional this winter.

I checkt the temperature with a infrared temperature meter to check that it won't burn out again.
My question:
How hot can the coupler get without damage?
During a test the temperature remained around 60 degrees Celsius.
Thank you,
Sander

 

[Scott06]

Hello,
We burnt out the rubber of our engine coupler. Don't now why, checkt the alignment at the start of the season with my self made alignment tool and this looked oke. I now bought a real alignment tool to be sure.

Pulled the engine, replaced the coupler, front engine mount and rear engine mounting hardware.
Engine alignment was harder than I hoped to get it right, I'm planning to have our work checked by a professional this winter.

I checkt the temperature with a infrared temperature meter to check that it won't burn out again.
My question:
How hot can the coupler get without damage?
During a test the temperature remained around 60 degrees Celsius.
Thank you,
Sander

Never checked coupler temp but being on back of engine next to the exhaust I’d say 140 f / 60 c is fine

if you have relatively even witness marks in the grease don’t worry about it. When I did my repower I could not get the grease marks perfect, spent a bunch of time back and forth ….
drive slid on and has worked fine for 9 seasons 380 hrs and I do a ton of watersports towing with a full boat …

 

[Lansselot]

Thanks for your response. That gives me a little confidence that it will be okay. Of course I am a bit cautious since we have not been able to find out why the old one broke.

 

[Scott06]

Thanks for your response. That gives me a little confidence that it will be okay. Of course I am a bit cautious since we have not been able to find out why the old one broke.

Were you able to check alignment after the coupler blew?

99 % of the time if the alignment is good and there is no engine sagging due to transom or stringer rot, the coupler will last the life of the boat if greased.

I assume it is a somewhat older boat being a 4.3 LX ? might be worth drilling some holes in transom and stringers to make sure.

Is the alignment tool you made (assume turned on a lathe?) the correct dimensions?