Engine seacock strainer on hull

[Cspirit]

As above, and I should know the answer but I don't......

Which way round does this go, grill end forward or aft?

 

[[194224]]

Narrow end aft for me.

 

[penfold]

I'd fit it grille aft, but I'd give it a miss; they grow things inside which can never be removed and likewise you can't get AF inside effectively to prevent them growing.

 

[Spirit (of Glenans)]

I wouldn't have one of those, but if I did, I would fit it narrow end forward, on the basis that I feel that in that orientation, forward motion would ram water in, whereas with the grill aft there would be a suction effect, similar to the self-bailer in a dinghy or rib, reducing the delivery of water to the cooling system.

 

[LadyInBed]

I'd fit it grille aft, but I'd give it a miss; they grow things inside which can never be removed and likewise you can't get AF inside effectively to prevent them growing.

 

[Refueler]

True that they can get blocked by stuff growing outside and inside of them. But imagine without ........

Then only one place for growth - inside the seacock / pipe work.

 

[Graham376]

True that they can get blocked by stuff growing outside and inside of them. But imagine without ........

Then only one place for growth - inside the seacock / pipe work.

Unlikely but, easy enough to rod out if no strainer.

 

[Tranona]

Beta specifically recommend a normal water intake with a ball valve and. an internal filter, preferably above the waterline. If an external strainer is fitted, the narrow end should face aft. Personally would not fit that type for all the reasons already mentioned.

 

[wingcommander]

I've just replaced a 1/2 " one with strainer like above with a regular 3/4"through hull and valve. Was always concerned about poor flow from exhaust and overheating. On removing the old i found it was 50% restricted with growth inside the ball valve. Now I can disconnect the hose from the raw water inlet of the strainer ( above water line ) and blow or poke right through even afloat. Also swapped out the strainer itself for a 3/4 plastic ebay version of a vetus . The original bronze 1/2" one was a pain to remove the lid , even after applying copious amounts of silicon grease to the seal.

 

[PCUK]

The correct orientation is grill forward. The sloping shape helps to deflect rubbish which would otherwise hit the blunt end much harder. It also acts as a scoop to increase water flow.

 

[Plum]

As above, and I should know the answer but I don't......

Which way round does this go, grill end forward or aft?




View attachment 146962

The strainer should face aft on a sail-boat but face forward on a motorboat.

www.solocoastalsailing.co.uk

 

[Jokani]

As there is not a consensus, may be fit it athwartships, that way you can't be more than 50% wrong.

 

[BabaYaga]

The strainer should face aft on a sail-boat but face forward on a motorboat.

+1.
As I understand, the argument is that the increased water pressure from a forward facing grill could, when sailing, force water past the impeller, into the silencer and potentially flood the engine.

I have this type, plastic strainer fastened by two small stainless bolts onto the flange of the brass through hull. Easily removed for cleaning and anti fouling on all sides:

BORDSGENOMFÖRING 3/4 M SIL

 

[vyv_cox]

When we took the Canal du Midi from Bordeaux to the Mediterranean our engine skin fitting blocked with leaves about 100 times. Having an open skin fitting was invaluable for rodding through with a brazing rod. With a strainer outside the hull I cannot imagine how we could have got through.

 

[superheat6k]

Not having these near wrecked the engine on my Corvette when the inlet completely plugged with shiny fronds of floating weed. As I understand it the grill should be aft, the idea being the bull section nudges the weed aside and it passes clear, whereas the water freely floods in sans weed.

I have certainly never suffered an overheat with these things fitted !

 

[ridgy]

On a similar note, what is the view on an external strainer on the heads inlet?

 

[TSB240]

We have one on our engine inlet fitted with grill facing aft to prevent hydrolocking engine due to ram effect whilst sailing.

We also have one on our cooling inlet for the stern shaft. This faces forward to encourage pressurised flow into the stern shaft!

Neither were blocked by any growth after 23 years use.

We have an exhaust temperature alarm. JIC.

 

[penfold]

I'm not philosophically opposed to external strainers, they have their place particularly in specific local conditions like yours, but the non-removable nature of the one illustrated makes my teeth itch.

Not having these near wrecked the engine on my Corvette when the inlet completely plugged with shiny fronds of floating weed. As I understand it the grill should be aft, the idea being the bull section nudges the weed aside and it passes clear, whereas the water freely floods in sans weed.

I have certainly never suffered an overheat with these things fitted !