Soot in coolant - need help!

[Scubaseas]

Originally Posted by Searles

On some of these engines the exhaust manifold and the heat exchanger top tank are open at the rear end and corrosion or a gasket failure will allow crossover,exhaust back pressure will do the rest ,back pressure at pull power must not excede 1.5 psi if greater chech exhaust system .⚓️����⛵️

See page 42 of for parts diagram of a 44B https://www.westerbeke.com/parts%20m...2.0%20btdc.pdf

Back pressure depends on your exhaust restrictions and water column if a wet exhaust, 1.5 psi back pressure isn't that much. Most cars will have abut 2psi back pressure at WOT. Diesels a bit more since they have over twice the compression which is why a diesel typically has a larger exhaust than a gas engine vehicle .