Yanmar 6lp cooling system

[jimbob2]

Would appreciate some guidance here - just had my boat looked at by a marine engineer- apart from tge glaring mismatch of a 6LP with a Bravo3, it was noted that the raw water cooling had been modified in such a way that sewater was pulled through a small strainer in teh hull (teardrop shaped thing) rather than through the outdrive. The engineer has recommend that this mod be reversed, the strainer blanked off and the cooling water brought tin through the outdrive.


For me this is an expensive job as the turbo needs to be removed from the back of the engine. I'm also conscious that if I leave the setup as-is, how on earth is my outdrive getting cooled if its not pulling in seawater?

I've also read somewhere that using water pulled in through the outdrive is not sufficient in volume to cool a 6lp correctly (presumably why the original mod was done)

To make things more confusing i've also read that I shoudl use both e.g. through hull and through outdrive as sources of raw water.

So i've three options

1. Leave as-is, and risk (in my mind anyway) the outdrive
2. Blank off hull strainer and pull water through leg, receive large bill and risk 6lp not getting enough cold water
3. Use both sources, somehow...

Thoughts?

[paulbrown22]

My 6LP + Bravo 3 combo uses both intakes, which I thought was the recommended way.

I also fitted an IMCO drive shower to the Bravo 3 as soon as I bought it to try and keep it as cool as possible, and haven't yet had any issues.

Regards,

Paul

[beamishken]

The split cooling system is standard on a 6lp the 1/2inch intake through the bravo drive doesn't flow enough water to cool the engine so there is a tee fitted to the port side rear of the belhousing which picks up from a 11/2"thru hull scoop & the drive.
The drive doesn't realy cool from the pickup water so if your only picking up through the hull it's not realy a problem assuming the scoop is big enough.A lot of bravo drives have the water pickup blanked off
As Paul says a drive shower is a good idea to keep the top of the drive cool on long runs

[Roy arelo]

I can't find the sea strainer on my 1995 yanmar diesel 6lym-ute inboard .. Can anybody help with some info ? Thanks !

[paulbrown22]

I guess it could be anywhere within reason - completely depends on the installation and where someone chose to site it. In a RIB, the engine bay is typically so small you can't exactly miss it, and they tend to be sited for easy access/cleaning.

And I guess some sea strainers are more obvious than others - some of the boats I use have non-transparent metal strainers painted the same as the engine colour, mounted low down right on the engine, and not instantly obvious.

If you can't see the strainer itself, can you see the water intake into the engine, or the through hull fitting, and trace the pipe along?