Exhaust Relief Ports

[Tucker]

Re: '98 S200's
Cheez searched 3-forums and found a variety of answers...meaning I'm not the only one that doesn't have a clue. Just want to know what they're for. Sometimes water spits out with steam, sometimes just steam, sometimes just water, sometimes nothing. Yea, it relieves exhaust pressure but when and how is it tied into the rest of the exhaust system? Can an untimely discharge be a indication of something going bad? Thanks gents.

[boats.net]

They are just relief holes but the high pressure valves will discharge water out if water pressure gets high enough to open valves. They are mainly for idle or low speed when exhaust can't easily go through prop.