Torque Specs for Mounting Outboard

ERock82

Petty Officer 1st Class
Joined
Aug 14, 2014
Messages
230
I just bought a 2003 Mercury 50hp 2 stroke motor. I mounted it on my transom yesterday but didn't know the torque specs for the transom bolts. I researched online and found anywhere between 30 to 55 ft lbs. I torqued to 35ft lbs for the time being. My buddy who was helping me said it looked like they would be getting too tight on the transom if I went much further but I don't really know. I would like to have them right though. They are 1/2" bolts and go on a 14ft Bayliner Capri. I don't know what my old Force was torqued to and the specs weren't in the manual.

If anyone knows what I should torque this to please tell. If you think 35ft lbs will be good, please let me know. Thanks.
 

gm280

Supreme Mariner
Joined
Jun 26, 2011
Messages
14,605
ERock82, I'm not so sure there is a set torque spec for tightening bolt to mount an OB engine. It would really depend on so many things. The construction being the main thing. I could easily see crushing the transom and gaining zero in effort by trying to arbitrarily reach some torque ft/lb rating. So using quality stainless steel fine thread bolts and lock nuts is probably the best possible thing you could do. I have never checked the actual torque myself, but I have never ever had any bolts work loose either. I know that really doesn't give you a verifiable answer, but I don't know of a specified torque spec myself... :noidea:
 

82rude

Rear Admiral
Joined
May 8, 2012
Messages
4,082
I checked on a few merc sites and they recommend between 30 to 40 ft lbs torque.Being careful not to crush the hull is a given also.
 

Sea Rider

Supreme Mariner
Joined
Sep 20, 2008
Messages
12,345
Just adjust arm tight with double nuts as recommended. If transom has plates at both sides, much better.

Happy Boating
 

82rude

Rear Admiral
Joined
May 8, 2012
Messages
4,082
At 35 lbs you should be fine .As an example heres my specs right out of page 53 in my owners manual for a 2011 60 etec.Every 300 hrs or 3 years, engine to transom mounting hardware,re-torque to 40 ft lbs.
 
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