I need to remove an exhaust manifold off my 454. Boat has twin 454's and of course it's the interior manifold. The bigger problem I am having right now is finding the correct size socket to remove the bolts. 1/2 in is too small and 9/16 is too big. 13mm too small and 14mm is too big.

Anyone have any suggestions or know the trick??

If it matters, boat is an 1989 Sonic 30 SS. Motors are twin 454 mags with Bravo 1 drives.

use 6 point sockets.

I have tried 6 and 12 point sockets

the bolts are 9/16 heads,at least they were before the rust,as mentioned earlier 6 point socket will get them out .

okay then, i will keep at it

thanks guys

Try a metric 6 point that almost fits ,Or if the 1/2 almost fits.. hammer it onto bolt head. Sacrifice the socket if necessary

Google Twist Sockets.

Turbo sockets

1/2 is roughly 13, 9/16 roughly 14mm. I have crapsman stripped bolt removers that grab anything.....

1/2"=12.7 mm=.5000"

9/16"=14.28 mm=.5625"