inboard advice

[bert]

don`t know much about inboards always had outboards please can someone help answer these questions


looked at a boat has straight through exhaust but no water passes through them instead has a jet coming out of the back of the boat is this normal if so how is the exhaust cooled


also has an alli head been told that this should not be cooled with raw water should have a seperate cooling system is this right

also with outboards you raise the height up for greater speed how does this work with inboards is it just trim tabs as this boat has none

[Jon Fuller]

what motor/drive/boat?

[bert]

5.7ltr mercruiser think bravo 1 but maybe alpha 1 boats up for sale so don`t really want to pick holes at somebody elses boat

[Ben]

Exhaust could be one of two things:

Dry - unlikely unless the engine bay is uncovered as lots of heat would be generated.

Water jacketed - far more likely. Water does not mix with the exhaust but rather circulates around the tailpipes thereby cooling them. The water can exit through outlets at the ends of the pipes or elsewhere.

Ally heads are often raw water cooled but must be thoroughly flushed with fresh water after each and every use.

The outdrive will trim in and out just as an outboard will. The difference is it won't move vertically.

[bert]

there is a flushing system in the boat which the boat should be run up on not muffs thats why there was no water coming from the exhaust also another pick up point so i have been told

why would you fit an ally head its not a race boat and will be used in salt water

also if you leave the boat in the water and attach it to a hose pipe surely it would still try and suck salt water through the leg