Exhaust Manifolds / 2 part question

Reming870

Petty Officer 2nd Class
Joined
Jul 15, 2010
Messages
191
5.7 L MPI / 2009

I leak checked my exhaust manifolds and have determined both are leaking. Osco 7114B2. Original problem was anti-freeze in exhaust system and getting on plugs. My setup has the manifolds cooled with antifreeze with a blank off plate separating the riser elbow.

1. Can my Osco riser elbow mount to a different manifold other than Osco? It appears I can get the GLM equivalent cheaper but I am not positive if the OSCO riser will mount to it.

2. Is it worth purchasing an E-Coating? I run antifreeze but I am assuming the leaks are due to the exhaust side and not the water side. I am not sure if the e-coating is also on the exhaust side.
 

Bt Doctur

Supreme Mariner
Joined
Aug 29, 2004
Messages
19,346
First you have to identify where the AF is coming from.Is it from a defective gasket , if using the SS block off plate with 2 gaskets or just a blocked gasket ? or just corroded surfaces.
Manifolds have been known to start leaking AF internally into the exaust port .
 

Reming870

Petty Officer 2nd Class
Joined
Jul 15, 2010
Messages
191
The manifolds are leaking internally due to corroded surfaces. I have determined that already and I need to replace them. Looking for advice on the e-coating and if an alternate manifold will mount to the Osco riser.
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,095
The manifolds are leaking internally due to corroded surfaces. I have determined that already and I need to replace them. Looking for advice on the e-coating and if an alternate manifold will mount to the Osco riser.

Ayuh,.... Generally speakin', manifolds, 'm risers designed as Merc replacements, use the Merc bolt, 'n gasket patterns,....

The GLMs certainly do,...
a note of caution, the GLMs I ended up with, had to be machined Flat at the riser joint, almost lost my motor,....
'n use the Merc metallic carbon gaskets, insteada the green paper stuff,...

Can comment on the e-coatin' never seen it,.... bein' freshwater cooled, ya shouldn't need it,....
 

Volphin

Lieutenant
Joined
Jun 5, 2011
Messages
1,405
I wouldn't use GLM as an anchor. I had a pair once... almost cost me a motor too. Internal cracks from shoddy castings. YMMV
 
Top