[Perkins S6M withP6M gearbox......]

New to the CW forum, so maybe I'm in the wrong section; but here goes !

Recently purchased a 1911 ex Royal Navy pinnace for restoration. She was converted to motor cruiser in 1951, so only the hull is original...ish.

Perkins engine and gearbox were fitted around 1977, but I doubt if they were new even then.

I'm about to carefully strip down the engine......suspected head gasket fault....hopefully not a problem...as it's now out of the boat and in my workshop.

Boat had a mishap last Xmas, and partly sank at the mooring.....prior to my purchase     Engine had already been drained of oil, and this week I pumped out 30 litres of the Aire and Calder out of it.

So far, so good. ! 

Can't find any details about the gearbox...…...oil fed, but manual operation using a long lever in wheelhouse, and shafts to the gearbox ...Could do with a repair/operation manual.

Needless to say, if the engine turns out to be beyond repair, then I will have to replace the lot...….Perkins Sabre maybe ?

The hull construction was originally built for rivers/estuaries and coastal...(not to mention battleships)…..so any replacement engine needs to be up to the job, with a few HP in reserve ? 

Thoughts anyone ?...especially on repair/overhaul of the P6M gearbox if necessary...…..if parts even exist ?