Originally Posted by LOOFOO
What causes white smoke in the exhaust of a 135HP Lehman?
Nothing good. Its either water vapor due to overheated exhaust or its incompletely burned diesel fuel.
Easy things to check:
Water flow out of the exhaust.
You should be able to hold your hand on the exhaust hose downstream of the riser and the riser itself.
Clean seawater intake strainer.
Heat exchanger sea water side blockage.
Worn out sea water pump/impeller/missing blades.
Diesel fuel in exhaust will have a strong smell. Water vapor, not so much.
Rebuild the fuel injectors.