Leak around stern gear

[Ricco1]

One of my boats has a simple stern gear set up. I can see 2 bolts that I could tighten to compress the gear a little, should I get a leak.

 

My other boat is a bit more complicated and to be honest, I don't understand much about it. There appears to be a thrust bearing. The greaser tube locates behind this. Further back still there are 2 brass tubes. There appears to be a screw thread joining these 2 brass tubes. I have a leak where the rear brass tube meets the hull of the boat. No amount of grease stops it. Actually grease is been squeezed out, further forward. I was wondering whether these brass tubes are designed to be adjustable (because there's a screw thread) and if the solution might be to apply a monkey wrench to try to cure the problem?

 

Apologies, it's probably not a good description, but any thoughts?

[Paul's Nulife4-2]

Any chance of some pics to help Ricco !

[Pete & Helen]

There are quite a number of different set ups, but I'm sure someone will have the same or one of the engineers on here will recognise what you have. Picture of the set up will help loads

 

ETA Paul beat me to the pic request but I was typing that bit so left it in

[Ray T]

Anything like this:

 

DSCF6100

 

The inner tube is held by a lock nut at the end of the outer tube. To adjust this you need C spanners

 

If you have water entering from the area where the outer tube exits the boat you may have problems which might need the boat out of the water to fix.

Edited August 11, 2014 by Ray T

[bizzard]

Yes the tube does usually screw into the steel collar on the sternpost and it is not that uncommon for a leak to develop there. You can try tightening it with Stilsons but in doing so will mean undoing and unbolting the whole tube assembly where the gland box bearing is bolted to your swim bracket or whatever and screwing in the whole assembly, which will mean at least one full turn to bring the greaser ect the right way up again.

If you just only screw in the tube which is leaking the other parts will unscrew and will leak.

[Ricco1]

I have a picture now, but I've no idea how to upload it on here!

[Ricco1]

Yes the tube does usually screw into the steel collar on the sternpost and it is not that uncommon for a leak to develop there. You can try tightening it with Stilsons but in doing so will mean undoing and unbolting the whole tube assembly where the gland box bearing is bolted to your swim bracket or whatever and screwing in the whole assembly, which will mean at least one full turn to bring the greaser ect the right way up again.

If you just only screw in the tube which is leaking the other parts will unscrew and will leak.

 

I've just had another look, the previously constant drip has now slowed down to a drip about every 5 seconds. Strange. As it's a slight leak, do you think there might be a way with a bodge job with something?

[bizzard]

 

I've just had another look, the previously constant drip has now slowed down to a drip about every 5 seconds. Strange. As it's a slight leak, do you think there might be a way with a bodge job with something?

This sometimes happens if the propeller has had a hefty clout hard enough to even stall the engine. The tube bearing threads get a sudden hefty jolt which seems to break up any hardened thread sealant and rust to cause the leak. That cause of the leak often reseals itself with muck in the water which flows into the tube and wires itself into the thread and reseals it. If that is the case and it probably is I think it will reseal after a bit, just keep an eye on it.

[Ricco1]

This sometimes happens if the propeller has had a hefty clout hard enough to even stall the engine. The tube bearing threads get a sudden hefty jolt which seems to break up any hardened thread sealant and rust to cause the leak. That cause of the leak often reseals itself with muck in the water which flows into the tube and wires itself into the thread and reseals it. If that is the case and it probably is I think it will reseal after a bit, just keep an eye on it.

 

Thanks, I'll do that. Would it be worth maybe winding a load of ptfe tape round it, pushing it in as much as possible, maybe a jubilee clip over it?

[MunkeyBoy]

Where are you based?

Boat surveyor Glenn at Captain Jacks boat yard is really helpful I've found, he's in Hyde down on the Lower Peak canal opposite Adamsons.

[beerbeerbeerbeerbeer]

This sometimes happens if the propeller has had a hefty clout hard enough to even stall the engine. The tube bearing threads get a sudden hefty jolt which seems to break up any hardened thread sealant and rust to cause the leak. That cause of the leak often reseals itself with muck in the water which flows into the tube and wires itself into the thread and reseals it. If that is the case and it probably is I think it will reseal after a bit, just keep an eye on it.

That's my experience too.

No leak for months, a knock and it leaks, then reseals.

 

Glenn