Bolt spec for Mercruiser 120 GM 153, serial 4xxx, at elbow assembly

Lawr

Cadet
Joined
Jun 16, 2013
Messages
17
Hi folks,

Iam looking for the specs of the bolts (4x) that connect the elbow assembly to the manifold, cf. attached picture.
Can anyone help ?

Thanks in advance.
 

Attachments

  • elbow.jpg
    elbow.jpg
    19.3 KB · Views: 0

Fun Times

Moderator
Staff member
Joined
May 16, 2009
Messages
8,776
Merc OEM service manual number 3 page 5A-1 or page 588 at boat info has the elbow at 25 Ft. Lbs. while the exhaust manifold is 23 Ft. Lbs. which needs to be re-torqued after engine has been brought up to operating temperature. Service manual # 2 doesn't show the specs for the elbow assembly but it's always been in the 25 Ft Lbs range for the elbow.

Sorry I'd link it but the hosts of iboats prefers not have that site linked all over their forum any longer mainly due to feared legal reasons.
 

Lawr

Cadet
Joined
Jun 16, 2013
Messages
17
Thanks, I will take the 25 Ft Lbs.
The threads inside the manifold werden replaced by metric ones because the threads were rusted.Unfortunately I lost the old screws. Do you know the screw size so that I can obtain new screws for the new manifold?
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,470
Ayuh,.... Stock is 3/8"- 16, by the length ya need,...
 

Lawr

Cadet
Joined
Jun 16, 2013
Messages
17
Ok thanks. I only have to figure out the length by measuring the bore depth.
 
Top