Posted: 21 July 2022
OIL CONDENSATION ISSUE FIX FOR FORD SABRE 250HP
Ford Sabre 250HP engines A-spec 1984 and earlier, that get condensation in oil when used at low power for lengthy periods.
The piston spray oil cooler is plumbed in the raw water circuit, very much because the engines were initially built with racing and high-performance sports cruisers like the Fairey Huntsman in mind.
From 1985 onwards on the B-spec engines, with more cruising boats in using 250HP and higher engines and with synthetic and semi-synthetic oils available that work well at higher temperatures, the oil cooler was re-located into the jacket water circuit so that it had water at 80 deg.C going through it, allowing a running oil temperature in the 100-120 degree region that evaporates off any condensate from combustion gasses that have passed the piston rings.
To update your system you could re-route the pipe that you have coming out of the back of the exhaust manifold round the back of the engine, through the cooler and up into the bottom of the heat exchanger, instead of coming round the front of the engine to get to the heat exchanger.
The raw water circuit should not be too difficult to re-route eliminating its passage through the cooler.
You can generally make a fairly neat job of this, re-using some of the original chromed piping, plus 32mm and 45mm straight hose and hose elbows that we can supply.