I've just finished a service/overhaul and paint on my short shaft Silver Century. Looks great and starts/runs well in the test tank.
After about 5 mins running I pulled it out of the test tank to see signs of dirty gear oil oozing from the lower of the water inlet slots. I wonder how this is getting there?
I changed the gear oil and to be honest this around the slot looks like the very brown oil it had before I did the drain/fill. During overhaul and painting it has been all ways up in the workshop and I wondered if this was oil that had drained there during that time rather than the fresh oil getting there during running??
The cooling flow is fine but I'm taking it for a river trial soon and worry the 140 oil is so gloopy it could just restrict water flow into the slots, the lower one in particular that already seems a bit narrow.
Any thoughts?
Thanks,
David
Gear oil oozing from water intake slots.
Moderators: John@sos, charlesp, Charles uk, RickUK, Petergalileo
Gear oil oozing from water intake slots.
40 Plus Longshaft 1977 (Serviced & painted) --Silver Century Shortshaft 1977 (Serviced & painted) -- A pile of Silver Century spares.
You might expect some oil to leak from the gearcase into the pump and out via the inlet slots if the engine is lying down but not while upright. Very likely it is old oil still finding its way out.
The other possibility is that it is oil from the exhaust finding its way out to the water intake via a defective jointplate or a badly fitting water tube.
The possibility that a little oil will block the water intake sounds pretty unlikely to me.
The other possibility is that it is oil from the exhaust finding its way out to the water intake via a defective jointplate or a badly fitting water tube.
The possibility that a little oil will block the water intake sounds pretty unlikely to me.
Thanks Vic... I'll not worry then.
Had it running on the local river (found every bit of weed and got it round the prop!) for an hour today and it went fine... seems after that initial bit of oil there was very little more. It could be old stuff flushing out.
David
Had it running on the local river (found every bit of weed and got it round the prop!) for an hour today and it went fine... seems after that initial bit of oil there was very little more. It could be old stuff flushing out.
David
40 Plus Longshaft 1977 (Serviced & painted) --Silver Century Shortshaft 1977 (Serviced & painted) -- A pile of Silver Century spares.
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Charles UK
The most usual source of this type of oil discharge is a worn pinion & prop shaft bearings.
Both bearings in the gear case are likley to be badly worn allowing water ingress through the prop shaft bearing filling the gearbox when the prop shaft is turning, displaceing gear oil through the pinion bearing into the space behind the water intake slots helped by the gearbox getting warmer when it is not in the water but in a summer warm shed, causing the oil emulsion to expand & weep out of the path of least resistance.
Both bearings in the gear case are likley to be badly worn allowing water ingress through the prop shaft bearing filling the gearbox when the prop shaft is turning, displaceing gear oil through the pinion bearing into the space behind the water intake slots helped by the gearbox getting warmer when it is not in the water but in a summer warm shed, causing the oil emulsion to expand & weep out of the path of least resistance.