I bought a 48ft boat (Samson Ferrocement) with a Leyland/Thornycroft 25V engine
that has not been run in years, and I was told it was 'pickled' due to 'water in the oil'. I have tried to find info on the engine
but so far not much luck.. other than it could be a marinized BMC 2.52 engine (which does not tell me much except that I was able to order a manual for it.. not here yet). What happened is:
I was trying to figure out if the engine was salvageable and bought a large wrech to turn the motor
main nut by hand. After applying quite a bit of pressure (wrench is about 18 inches) I was able to get it to turn counter clock wise as seen from the front (I am calling the rear the side that has the propeller
shaft). I was so happy it moved I continued for about 1/4 turn until I heard a loud 'clank' from inside the engine. I got worried and moved it back 1/4 turn clock wise, it seems to move without much effort now. My questions are:
1) Do engines get damaged if you turn them in the 'wrong' direction? (I dont know which way the engine is supposed to turn.. cw or ccw?)
2) Can the strength of a guy times 18 inches produce sufficient torque to bust something inside the engine?
3) I have not opened any glow plugs or anything.. is it possible if fluid was inside the cylinder that I may have broken something by fluid compression
4) The transmission
control was frozen all the way forwards (towards the front of the ship) while the above happened, so afterwardsI took a mallet and a wrench and banged it until it was vertical, hoping that means neutral. Could being in gear
have been part of the noise
I dont know much about engines.. how do you recommend I proceed? Take the glow plugs out? (I didnt really wanted to open the engine), take the valve cover off (and look if everything still moves?), just connect power to the started and give it a go?
I really want to try to get the engine started (mainly since the local re-power shop told me a Yanmar
re-power is typically 11K for the engine and another 11K to put it in). Any advice in to what to start replacing first (starter,generator, belts, fuel
pump, etc) and in what specific order recommended would be greatly appreciated.
P.S. And if anyone has information on Leyland Thornycroft 25V engines.. (like a manual) please share it with me.