Engine Cooling

[wilhelm]

We have a Bukh, fwc, 36hp in our lm 27, the sea water cooling has two hull intakes with water filters hoses joining joining together past filter then fed to engine block. Has any other member have installed the same set up?. Cant understand why other than its belt and braces should one feed get restricted. Our intention is to remove one during winter  lay up. We also intend to move bilge pump from existing position allowing easier access. 

[Sula]

I've also got a Bukh DV36 in an LM27. It is direct (sea water only) cooled, and only has a single hull intake, just forward and starboard of the engine.

Like you, the only reason I can think for having two is 'belt and braces' in case one hull inlet is blocked.

[Brian & Glenda]

We have a single engine cooling through hull on our LM32 with a Bukh DV36 SME. Ours is fresh water cooled, but with a non-Bukh heat exhanger. I believe it is a 1" diameter through hull, (but would have to confirm) with a screened inlet similar to the Groco Hi-Speed Strainer noted at:

www.wholesalemarine.com/groco-hi-speed-strainer-with-nut-79054.html

It has served us very well though the 4+ years we've owned the boat. No blockages, and the engine cooling is entirely adequate.

[wilhelm]

Many thanks for comments, decision made, one intake will be removed this will make room to install electric bilge pump. Must comment having had Yanmar & Volvo installed on previous boats,the Bukh 36hp, brilliant bit of gear no shake rattle & roll, its a dream.

Regards Wilhelm

[Brian & Glenda]

Two interpretations are possible for your phrase "... this will make room to install electic bilge pump." I hope your intention is to only place the pump over the then sealed space that the through-hull now occupies; and that it is not your intention to use this second raw water inlets through hull, as the new bilge pump's discharge.

Just in case your intent is the later, I offer that:

I definitely would not run a bilge pump discharge through an underwater through hull ... as the though hull valve would have to be left open at all times if the pump is to serve its purpose, and such an installation would be prone to siphoning the seawater into your bilge, the exact opposite of your objective! Such an installation would be also contrary to the ABYC installation requirements for bilge pump installation, and probably invalidate your insurance.

You would have to at the very minimum, install an anti-siphon loop that extends well above the actual waterline at all inclinations while sailing, but that probably would not be enough to satisfy any installation code or insurance requirements.

But I'm sure the later was not your intent...

Cheers,
Brian.

[wilhelm]

Hello Brian, My comments regarding fitting elec. pump was reference to space following removal of the second water filter. Under no circumstance would I use below water line fitting for electric pump outlet. Thanks for your comments.