Cold riser vs Warm riser

[tavo83]

Hi!
New to this forum and to sterndrive engines.
This fall/spring i will be replacing the manifolds and elbows on my 383 mpi from 2006.
Although the service manual states that its a MX 6.2 (guess its the same)
From the looks of it the system thats installed today is a wam riser setup, but in the service manual (going by serial number in the engine) it should have a cold riser setup.
The engine runs fine and cools as it should (70 degrees Celsius)
Anyone here know the difference between the two?

 

[Scott06]

A warm manifold set up will have two hoses constantly feeding cold water the risers snd two hoses feeding water from the thermostat when open to the bottom of the manifolds. This just keeps the manifolds at engine temp to keep condensation out of them. Either set up works fine if the engine is cool leave it alone

 

[tavo83]

thank you!