Sail drive blockage

[Bradders]

Hi All
I went to move my boat after it had been left a while in the Orwell, started the engine and no water flow. I have a generator on board with a through hull fitting, could I hook up the generator water inlet to the engine cooling system therefore by passing the water flow through the sail drive, or does the sail drive rely on this water flow for cooling … obviously the best solution would be to use the boat more often but due to my wife’s health this isn’t possible,
Any advice appreciated … thank you

 

[Daydream believer]

Try reversing. I did this and a polythene bag surfaced at the bow. The saildrive should be Ok as it is totally submerged in water & geared. It does not carry engine heat such as exhaust gas

 

[jlavery]

If it's a Volvo Penta 130s, then you should be fine. I bypassed the saildrive intake permanently and it was fine.

To clear the blockage, try disconnecting the raw water inlet pipe and either pumping down it or blowing down it. The latter worked for me when I had a blockage.

 

[Lucky Duck]

If it's a Volvo Penta 130s, then you should be fine. I bypassed the saildrive intake permanently and it was fine.

To clear the blockage, try disconnecting the raw water inlet pipe and either pumping down it or blowing down it. The latter worked for me when I had a blockage.

I found the dinghy pump ideal for ‘blowing back’ to clear weed blocking the sail drive intake in the same river as the OP.

We also suffered what likely a bag temporary causing the blockage in the upper reaches of the Thames which wasn’t particularly fun.

 

[Tranona]

Yes. Some boats rely solely on an independent water supply. while the leg relies on water to maintain temperature it does not require flow.

 

[Neeves]

From memory - you should be able to pass a flexible pipe, rod, through the water inlet on the top of the sail drive all the way through which would remove the blockage. You need to disconnect the engine, obviously, and then pass a rod through the inlet. Once cleared water will flow into the bilges so you need to be ready to re-connect.

My memory may be flawed.

Jonathan

 

[seeSimon]

Hi All
I went to move my boat after it had been left a while in the Orwell, started the engine and no water flow. I have a generator on board with a through hull fitting, could I hook up the generator water inlet to the engine cooling system therefore by passing the water flow through the sail drive, or does the sail drive rely on this water flow for cooling … obviously the best solution would be to use the boat more often but due to my wife’s health this isn’t possible,
Any advice appreciated … thank you

Yes, use gene supply.
...And blow back down the main line to try clearing it.

I carry a cross over hose to connect my loo flushing sea inlet to my engine SW strainer.
As a precaution against sucking too much mud or sand thru my sail drive (I often navigate shallow river estuaries) or having dried out on mud, I've recently fitted a second "high sea inlet" permanently piped. This is about 12" above, and forward of, the saildrive so hopefully will be in clean water.

My Beta Technodrive/Twin Disc saildrive says that the unit relies on water flow for gear cooling. I wouldn't run it at high speeds/loads for extended durations (without SW flow), but then I rarely do that anyway...I'm sure immersion will be enough.

 

[PabloPicasso]

On a 120s i found critters grew in the inlet pipe and blocked it.

Despite several seasons trying to keep it clear in the end I fitted a new thru hull and by-passed the saildrive inlet completly.

Never had any more issues after that.

The saildrive integral water inlet is narrow, long and twisty. A poor design in my opinion. If its blocked by mud or a plastic bag blowing back with a pump may clear it. If it is marine critters growing in the pipe I'm afraid you'll find it very difficult to do anything that makes a difference while afloat. You can't even use acid as it is aluminium which reacts badly.

Yes, fit a Y peice from your generator inlet. That should work very well indeed

 

[Neeves]

Replacement of the inlet faucet on the sail drive to a dedicated inlet located close by in the hull is common practice by the Volvo dealer/service agent here in Sydney.

The inlet on the sail drive is actually quite generous, an inlet in the base of the unit and 2 x 3 inlets as 2 inlet rows. at the back of the leg. But the leg design is such that plastic bags can easily wrap round the leg and 'seal' the inlets if you encounter polluted waters (it was a big problem in Hong Kong and one crew member was always ready to go overboard).

Jonathan

 

[PabloPicasso]

Replacement of the inlet faucet on the sail drive to a dedicated inlet located close by in the hull is common practice by the Volvo dealer/service agent here in Sydney.

The inlet on the sail drive is actually quite generous, an inlet in the base of the unit and 2 x 3 inlets as 2 inlet rows. at the back of the leg. But the leg design is such that plastic bags can easily wrap round the leg and 'seal' the inlets if you encounter polluted waters (it was a big problem in Hong Kong and one crew member was always ready to go overboard).

Jonathan

The inlet is, as you say, large enough, but isn't the internal tube from the inlet winding its way through the saildrive leg long, narrow, and along a twisting route. This means one cannot use a rod to clear it.

The inlet can, and does, fill up with marine critters, sometimes surprisingly quickly. Not an area that is easy to anti-foul either.

Fitting a thru-hull seems to be a useful way of resolving things.

 

[Bradders]

Thanks all for your replies - very much appreciated, I’ll carry out the cross over now in confidence

 

[Moodysailor]

The inlet is, as you say, large enough, but isn't the internal tube from the inlet winding its way through the saildrive leg long, narrow, and along a twisting route. This means one cannot use a rod to clear it.

The inlet can, and does, fill up with marine critters, sometimes surprisingly quickly. Not an area that is easy to anti-foul either.

Fitting a thru-hull seems to be a useful way of resolving things.

This

Short term fix is to try and rid through or backlash.
Long term, cap off the s/d and fit a dedicated through-hull with strainer.