Fitting a new raw water strainer

[domfoy]

Hi, I have a venerable Volvo MD11C engine in my Trapper 700 with a saildrive. There has never been any raw water strainer fitted so whatever gets through the intake on the saildrive gets into the engine. With this in mind I intend to fit a water strainer between saildrive and water pump. I am advised to have it positioned above the waterline. I would like to place it about 12" above the waterline so that it can be mounted in the bottom of a cockpit locker for easy inspection. My question: is it likely to be be an issue to have two 18" runs of hose to / from the strainer? Harder work for the pump thus risking failure?

Thanks for any advice.

 

[vyv_cox]

Here's mine. As you see, far longer than yours will be, no problems at all. Make the hose bore a size bigger if you have concerns.

I find it far more convenient to have the strainer in the engine compartment, if it can be arranged.

 

[VicS]

FWIW Vetus recommend a minimum height from the wl to the bottom of the strainer of 15cm.
However the the higher it is the more likely you will be to have priming problems and trouble from air leaks
See the diagram in their catalogue

There is also a table of recommended hose bore vs cooling water flow rate. No mention of hose length though

(I dont know the flow rate for an MD11C less than any quoted in the table I'd guess )

http://viewer.zmags.com/publication/dde28f6a#/dde28f6a/60

 

[Burnham Bob]

i had one of the vetus strainers with the clear platic top installed above the waterline. at the start of every season, simply unscrew the top and top up with water. start with the seacock closed but once the intake and out take are covered you can open it with no problems. the strainer stays full and the the pump then doesn't need to prime.

this way also measn your impeller never rus dry priming the pump

 

[vyv_cox]

I do the same. Also check it ashore by running a hosepipe with a pistol nozzle into the strainer. Save a lot of messing with buckets and hoses.

 

[mitiempo]

You posted "between the saildrive and water pump"

The strainer should be between the through hull and the water pump.

 

[Tranona]

You posted "between the saildrive and water pump"

The strainer should be between the through hull and the water pump.

The water inlet on the Saildrive is actually in the saildrive housing - not a separate through hull.

 

[mitiempo]

I see, but if possible I would install before the pump. If not possible after.

 

[VicS]

I see, but if possible I would install before the pump. If not possible after.

The Op said, "I intend to fit a water strainer between saildrive and water pump".