MF805 water in engine compartment

[davidprice]

Hi everyone.
I've recently bought a 2007 MF805. Delighted with boat but alarmed to find engine room bilge with about 8inches of water after a lot of rain.
Eventually found that the lazarette hatch channel drain blocked with debris and water getting passed hatch rubber seal and into the locker.
Can't understand why bilge pump pick-ups located in small sump by shaft rubber seal and not in engine compartment which is the lowest point.
Also why only one hatch channel drain which can easily block up.
Anyone else with an 805 had similar problems?
Regards.

 

[PaulGooch]

Not had this problem, but as a fellow 805 owner i can say that i feel the bilge pump layout on the 805 is somewhat lacking (actually, it's pi55 poor).

First and foremost (and super important), the hatch shouldn't be letting a lot of water in, IMO. Might just be that rainwater slowly seeped in, which wouldn't be too bad, but you don't want too much water getting in too easily. I would also suggest that you keep the locker secured when under way, as any water entering the cockpit could get into the locker. It's easy to get water coming in over the bathing platform and beneath the transom door if you come off the plane quickly. Having the hatch insecure could allow some of this water into the locker.

It's worth sticking a hose into the drain and blasting it through from time to time.

The bilge pump, shower tray pump, fresh water pump, fresh water accumulator and filters for all three pumps are located beneath the cupboard that the sink is fitted into. Access is via a removable panel in the lazarette locker, starboard side, front of the locker. Putting the bilge pump filter in there is a huge mistake. Getting to it and cleaning it out is a pain and in an emergency, it could give you serious problems. I fitted another filter, the same as the one already fitted, in the lazarette. Cut into the pipe from the bilge sump to the pump, in the lazarette and fit the filter in line. Nice and easy to get to when it needs cleaning. The other filters don't have to deal with the dirt and cr4p the gets in the bilge, so an annual clean is usually enough.

If you get too much water in the engine compartment it escapes into the void between the hull and the hull liner, via some 2" ish holes beneath the engine. This sloshes back and forth and is also a pain, as you keep thinking you still have a leak. You go on the plane, the water rushes into the lazarette via a hole in the stern end of the liner, near the rudder stock. You come off the plane and it runs into the bilge sump, then overflows back into the engine compartment. Ad infinitum. You'd need to get on the plane, with someone else at the helm, as the water runs into the bilge sump, keep pumping it out. When it's almost gone, sponge the rest out of the void through the 4" hole in the stern end of the liner.

The lack of an auto bilge pump, or any form of bilge pump in the engine compartment is poor design, in my opinion. I've fitted an auto pump in the very front of the engine compartment.

Overall, i'm very happy with the boat though. If you have any other questions about the 805, don't hesitate to post them here. I've nosed around the boat and am pretty familiar with it's systems.

 

[davidprice]

Thanks for the info, Paul.
I think I'll do what you suggest and fit an auto pump into the engine compartment, good insurance.
I've located the big hole in the liner of the lazarette at the back but couldn't see the 2" hole in the liner in the engine compartment when I looked this morning. Perhaps I need to take a closer look.
I'll be in touch through the forum if I have any further questions.
Regards.

 

[PaulGooch]

Thanks for the info, Paul.
I think I'll do what you suggest and fit an auto pump into the engine compartment, good insurance.
I've located the big hole in the liner of the lazarette at the back but couldn't see the 2" hole in the liner in the engine compartment when I looked this morning. Perhaps I need to take a closer look.
I'll be in touch through the forum if I have any further questions.
Regards.

You need to stand on your head in the engine compartment and look beneath the engine. You'll actually find four holes around 2" diameter. Worth remembering if you ever fancy washing the engine/engine compartment, as it's a bugger to get the water out from between the hull and the liner (don't ask how i know this).

 

[hlb]

All boats need at least Four different systems.

In all compartments.

First is, water proof decks. But they only work up to a point.

Second is auto bilge pumps, but they fail all the time.

Third is auto high water alarms.

Forth is a manual wander hose.

 

[Tresner]

All boats need at least Four different systems.

In all compartments.

First is, water proof decks. But they only work up to a point.

Second is auto bilge pumps, but they fail all the time.

Third is auto high water alarms.

Forth is a manual wander hose.

You might also keep a little piece of red wire on hand to keep the drain holes open. Critters and debris build up quickily. Limber holes are the first to get clogged.

 

[simmy]

You need to stand on your head in the engine compartment and look beneath the engine. You'll actually find four holes around 2" diameter. Worth remembering if you ever fancy washing the engine/engine compartment, as it's a bugger to get the water out from between the hull and the liner (don't ask how i know this).

Paul helped me out some time ago when I had the same problems (Cheers Paul) but my water ingress was via a big beam sea with the water entering through the engine compartment air-vents. It took a while but I did manage to get rid of it all, with the most interesting bit trying to pump out the water from the hole at the rear of the lazerette whilst on the plane! I suggest you pick a very flat calm day for this activity.........

One of the holes beneath the engine is visible through the service hatch located beneath the steps (You'll need to remove the middle step to get access) - This access allowed me to clean the forward area of the engine compartment thoroughly.