Mercruiser fuel pump tensioner help

[samm835]

So I have a 96 mercruiser, I had to put a new v-drive belt on my fuel pump. I got everything on but I can't keep tension on it. Is there a trick to tighten this freakin bolt for the tensioner? I'm about ready to put a bullet in this motor lol!

 

[alldodge]

Its a 96 Merc, WHAT????

Serial numbers work best

 

[samm835]

Yup....looks like I got a head of myself and left out some important information. You can't read my mind on what motor I have? It's a 96 mercruiser 7.4 with carb. I looked for the serial numbers today but I couldn't locate. Here is a picture of what it looks like behind the pulley tensioner.....I've never seen something like this, how in the hell is it supposed to tighten and stay tight?

 

[Bt Doctur]

loosen the 5/8ths nut a bit, using a 5/16ths socket on the hex shaft rotate to tighten belt , hold in position, tighten nut with a 5/8ths open end

 

[alldodge]

That is not an issue, take a 5/8 boxed end wrench an loosen the nut on the other side. Take a 5/16 boxed end wrench and place on the small end of the bolt extending out inside the larger nut. Turn the 5/16 until tension os correct, then hold the wrench still and tighten the 5/8 wrench

Eazy Peezy

 

[samm835]

Thanks for the help!!!