Mahe 36: Relocate raw water seacock from 120s saildrive

[Rufduck]

I am sure this has been discussed but can not find so here goes.

Mahe 36, VP D1-30B. Raw water pickup in drive leg. 48*f water. Muscle growth in drive leg has restricted water flow to the point that engines run at 200*+ at all power settings.

Have tried rodding out from the seacock on the drive. Can only get the top 7” to where the pipe bends.

Water too cold for this old body to enjoy diving under and rodding up from the bottom of the drive leg and this is a temporary fix anyway.

Want to fix the issue permanently and relocate the seacocks as suggested on the list but no one says to where. The best place appears to be aft of the drive gasket on the “flat” area before the muffler. Yes? No? Better choice?

Cheers RUFDUCK

[redneckrob]

Originally Posted by Rufduck

I am sure this has been discussed but can not find so here goes.

Mahe 36, VP D1-30B. Raw water pickup in drive leg. 48*f water. Muscle growth in drive leg has restricted water flow to the point that engines run at 200*+ at all power settings.

Have tried rodding out from the seacock on the drive. Can only get the top 7” to where the pipe bends.

Water too cold for this old body to enjoy diving under and rodding up from the bottom of the drive leg and this is a temporary fix anyway.

Want to fix the issue permanently and relocate the seacocks as suggested on the list but no one says to where. The best place appears to be aft of the drive gasket on the “flat” area before the muffler. Yes? No? Better choice?

Cheers RUFDUCK

Sorry I don't have an answer for your original question because I'm still stuck with the poor original design on my Mahe. But having had the same problem I did achieve some success by taking the intake hose off the filter (so the other end was still attached to the drive/seacock) and then getting one of those old school twist hose nozzles on a garden hose and stuffing it down the hose until it sealed and then blasting hose water backward through the seacock system. That cleaned it out well enough to increase water flow from about now until the water was warm enough to dive in here in MD. Good luck!

[chrisr]

not a mahe, but we have just done this job (installed direct skin fittings for raw water intake n by-passed legs) on our cat. yanmar SD31 legs / 4JH engines

we were recommended by several mechanics etc to fit the new sea suction in front of the engine - not behind. apparently the view is you get cleaner suction in less disturbed water.

of course this suited us as the 4JH water pump is at the front of the engine, and i'm not sure where yours is ?

cheers,

[Rufduck]

Redneckrob and Criser,

There is no visible growth within the clear tubing nor in the strainer. However, I went one better and made a short length of 3/4” ID tubing and a female garden hose end. After rodding as far as possible and trying wire coat hangers ad nausium to try to get around the bend, plate, whatever at the top of the leg, I coupled the garden hose and cranked it up. Linda said she could see water exiting the leg. At least it eliminated some detritus. I had planned to dump half a bottle of muriatic acid into each leg and let it cook for 20 minutes but could not find the acid. Maybe a good thing?

The Mahe engine is mounted backwards from a service standpoint. The raw water pump is at the forward end of the engine, the saildrive at the aft end and access is above and behind the saildrive. I replace the raw water impeller by pulling the pump (by Braille). Repositioning the seacock ahead of the engine is possible I suppose but accessing it to open or close it is not from a practical standpoint.

Thanks for your thoughts.
Rufduck

[Kiwicrew]

I have also had this problem. I stuffed screwdrivers, wires, and all sorts up and down the holes and although that dislodged some growth, what did finally
fix it was the dinghy pump. I took the inlet hose off the sea cock and taped that part of the dinghy pump hose that goes into the dinghy onto the inlet hose and pumped. After a bit of pressure there was a mighty whoosh in the sea water as it all came free.

This method had the added benefit of success being clearly audible from inside the engine bay.