Flush through Raw Water SailDrive

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fireball

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Having just had the boat out for the first time we now need to clean/prep for winter ...

I note that the saildrive has the outboard style water intake on it - does this mean I can attach some Outboard Muffs and run the engine to flush the raw water side?
 
Yes ... or you could be clever and flush it with antifreeze .... that way you put inhibitors in as well as making sure no residual water ends up freezing in it ...

I run antifreeze through my raw-water cooled Perkins diesel when laying up ...
 
On my Volvo 2001 with saildrive, I remove the hose from the saildrive, lay it in the bilge under the engine and run a hose into the bilge which is 'self contained'. Then I run the engine adjusting the water flow through the hose as necessary. That flushes the engine and if I want to run antifreeze through it I stick the end of the hose into a container of antifreeze mix.

I've never thought of flushing the saildrive but it is a good idea. I should be able to do it by passing water down from the seacock in the boat. There is no pump in there so it should just flow through.

If you use muffs, you may have trouble covering all the holes. On the Volvo, there is also a hole at the bottom of the saildrive as well as three? each side.
 
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Didn't notice a hole in the bottom - well a bung could sort that I guess ... I'll try and have a proper look this weekend when I've got more time ...
Otherwise, I've got to crawl over the engine to detach the hose from the saildrive as it is on the port side and I've only got access from the front or starboard side ... Doh!
 
Forget the "ear muffs" or removing hoses, if your installation has a raw water strainer there's an even easier way.

I would assume the strainer is fairly easily accessible, is before the water pump and above the waterline. If so, simply remove the lid, open the seacock to the leg and fill the filter chamber from a hose. With a bit of luck you will find fresh water pouring out of the holes in the leg, keep filling until you're bored/happy it's flushed enough.

I discovered this on mine by accident as I was trying to flush the engine and cool it by putting water into the filter and it kept running out of the leg! I had to close the seacock to stop it. You can flush both ways like this, the engine and the leg.


Hope this helps.

Tim
 
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fireball said:
Didn't notice a hole in the bottom - well a bung could sort that I guess ... I'll try and have a proper look this weekend when I've got more time ...
Otherwise, I've got to crawl over the engine to detach the hose from the saildrive as it is on the port side and I've only got access from the front or starboard side ... Doh!
Click to expand...


Are you sure? The Bav I know has engine access both sides.
 
The heads is on the port side - and there is no access panel .... it's not too difficult to reach the seacock - although wouldn't want to when the engine is hot ...
 
I didn't look for a hole in the bottom ... it's my first ever saildrive .... so steep learning curve this winter!

Anything else I should look for or do specifically to the leg?
 
Anode - particularly if you have a bronze prop. Will be obvious if it needs replacing. If it hasn't been done, replace the seals in the bearing housing. Bit fiddly to do - particularly getting the housing off and you ideally need a press to dismantle it and remove the seals. but less than 2 hours for an experienced mechanic so may be worth getting it done - I got charged an hours labour extra from a normal service. Also change the oil - has to be drained anyway.
 
fireball said:
I didn't look for a hole in the bottom ... it's my first ever saildrive .... so steep learning curve this winter!

Anything else I should look for or do specifically to the leg?
Click to expand...

Use an antifoul paint that is compatible with aluminium (one that doesn't contain copper). I use Trilux. Use this on the leg and on the hull in the surrounding area. I paint the rubber seal and about 6" beyond.

Otherwise anode check/change and oil change if needed, replacing the oil drain seal with a new one. Check old oil for water contamination.

Bearing housing seals can fail but I don't know when would be the best time to change them other than just before they fail. ;)
 
Nip down to B&Q and buy a "Muckbucket"

muckbucket.jpg


Use some wood blocks underneath it so the rim of the bucket just about touches the hull (or the leg touches the bottom of the bucket), fill with water, run engine......

It's worked for me for 10 years or so now, and is much easier than trying to disconnect the pipe from the seacock that leads to the water pump. That pipe is only about 4/5 inches long, and can be a right bugger to get off and back on.

As a refinement, if you can get a large diameter pipe from the exhaust, you can kep the bucket topped up from there, rather than running fresh from the hose all the time.
 
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It does sound like some-one has put a longer pipe on to replace the Volvo original.

Like Fireball, I don't have access to that side of the engine, and it's a **** job just trying to get to the jubilee clips, let alone trying to pull the pipe off the seacock fitting and the metal pipe to the water pump.

For winter lay-up, if the engine has been run recently, fill the bucket and off you go. I used to run the engine for about 20 minutes (keeping the bucket full all the time), then stop it and change the oil and filter. This gives the engine a chance to warm up enough for the thermostat to start working. Then I used to add inhibiting oil to the water, and run the engine for another 15 minutes or so.

However, I think Volvo have now stopped selling inhibiting oil, probably due to environmental concerns. Disposing of the mix responsibly after use was always a bit of a headache....

After the 15 minutes or so, remove the mix so the pump runs dry for a minute or two, and blip the throttle a few times to blow the mix from the exhaust. If laying up, then drain the block, and take out the impellor.

In the spring, just before launch, leave the old deisel filters in place, turn the engine over till it's just firing, then shut down. Fill the bucket, put in a new pump impellor, (with a bit of washing up liquid to help give it lift), open seacock, and fire up the engine and when you're sure water is going through, run it till warm.

Shut down, shut the seacock, change fuel filters, bleed to the injector, and crank the engine till it's just starting to fire, shut down, open seacock, the start it up again and run warm.

I've found it much easier to get the engine going again with new filters when the blocks warm, rather than changing the filters before running.
 
Rustyknight said:
fill the bucket and off you go. QUOTE]

I still prefer the raw water filter method as per my post above. If you haven't tried it and it's possible, it really is so simple. I tried the "bucket" method and got very wet and still didn't manage to get all the inlet holes on the leg submerged so sucked more air than anything. Admitedly this is on a Lombardini not a Volvo so inlets may vary. :D
Click to expand...
 
I think the "bucket" I use holds 39 litres when full, and has a depth of just over 16"". When blocked up till the brim of the bucket just touches the hull, the top inlet hole in the side of the leg is about 6/7 inches below the water level.

One problem Fireball might have with this method though is raising the bucket high enough. My Jaguar is the Bilge Keel version, with a draft of 1.1m, so the bucket only needs raising by 8 inches or so.

With a deeper draft fin keeled boat, something a bit more substantial might be needed (workmate bench + blocks maybe?)

As is normal with boats, what works for one might not work for another, but the above works fine for me.
 
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If you only have a short inlet pipe then presumably you do not have a filter. On Fireballs Bavaria (same as mine) there is a long pipe from the seacock, over the back of the engine to a filter on a bulkhead the other side and then down to the pump.

Therefore much easier to run water into the filter body to run fresh water through the engine (with the seacock closed) and backflush the leg with the seacock open and the engine not running.
 
You're correct.... my installation doesn't have the filter, though so far that's never been a problem.

As I mentioned above though, the best solution to the problem will vary to fit everyone's own circumstances. It would be probably be boring if they did.... :)
 
Well - had a better look over the weekend and I think we'll be going with the hose in the waterfilter trick as it is easy to get too and means I don't have to get the muck buckets out - we don't have a tall keel, but it would still need a work bench down there to support the bucket ... would try the muffs, but we can add some antifreeze this way...

Looks like we need a new anode on the saildrive too .... pity as there is plenty of material left - just can see (what I assume to be) the fixing bolts .... bum!
 
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