Logo
FULL SITE MENU

When to Replace Manifolds?

J

jayj123

New member
Had a mechanic tell me I needed new manifolds/Risers since it's been more than six years. I use an IR gun to check the temps on all the exhaust components every couple of times I run the boat. All temps are consistent and match with the water temp gauge at about 140 to 160. No hot spots anywhere. Wouldn't a problem with flow/clogging cause overheating or hot spots before needing to change them out? The exhaust is FWC. Just wandering....
 
if the exh. manifolds are FWC, then they will go over 20 years. Elbows, being RWC, good for only 4 to 5 in the ocean.
 
There is a failure mode with elbows where they do not run hot, still flow well, but can dump sea water into the engine via exhaust ports.
Best to replace them on a schedule. There is some evidence that flushing the engine after every run with fresh water prolongs elbow life. Flushing with saltaway even more so. On most boats, fresh water flushing requires some plumbing modification. My raw water inlet is thru hull and I have a T and a valve permantely plumbed in so I can flush and winterize easily.
 
Back
Top