1996 272 Sailfish Drainage tubes

[Gmack76]

Can anyone explain some specifics for me? I thought there may be a diagram in my owner's manual but there isn't. I believe I have an obstruction somewhere and began snaking it yesterday afternoon and have the following questions?

From the forward bilge area (where the forward bilge pump is located), is there a drain tube? If so does that tube continue all the way to the aft bilge? Or does it drain into the fuel tank cavity where a second tube runs from the back of the fuel tank cavity into the aft bilge?

Thank you. This will help me determine how to snake it.

 

[seasick]

In general, the forward bilge should not drain into the tank coffin There may be a continuous drain tube that passes under the tank or there may be separate tube to one side of the tank stringer.

Either tube cab get plugged up. It also can be easier to find the aft end of the tube and snake forwards as opposed to snaking from the mid section aft.

Note that on many Grady hulls and other makes too, the mid bilge will often have standing water since the mid bilge section may sit lower than the aft bilge.
The only sure way in that case to see if the bilge is draining correctly to to raise the bow so that the keel is slopped aft. Water in the mid bilge should flow to the aft bilge. If it doesn't and the mid bilge gets a significant amount of water (deep that is) then your drain tube or tubes are probably blocked

 

[Hookup1]

Can anyone explain some specifics for me? I thought there may be a diagram in my owner's manual but there isn't. I believe I have an obstruction somewhere and began snaking it yesterday afternoon and have the following questions?

From the forward bilge area (where the forward bilge pump is located), is there a drain tube? If so does that tube continue all the way to the aft bilge? YES

Or does it drain into the fuel tank cavity NO - The forward bilge drains to the aft bilge.

where a second tube runs from the back of the fuel tank cavity into the aft bilge? There are two 1" PVC couplings that act as limber holes. One under the forward/aft fuel tank bulkhead and one under the aft bulkhead.

Thank you. This will help me determine how to snake it.

I replaced my fuel tanks on my Islander this Summer. Still finishing up. Your question about how the forward, fuel compartment and aft bilge are managed is one that bugged me for a long time. A Islander is a little brother to a Sailfish. Other than the beam the boats are pretty much the same.

That 1/2" pipe should be snaked from the aft bilge (remove small aft deck) to the front bilge. Then clean the complete forward bilge and vacuum up the debris you can get out. It's too hard to do from the forward end. You will be trying to push the blockage all the way thru to the aft bilge and may wedge it in there. Don't ask me how I know that!

This is from my post on the tank replacement whit a few updates:

Next is to investigate the amount of water in the fuel compartment and how the drains should be working. The boat has a long 1/2" PVC pipe from the forward bilge to the aft bilge. There are 2 - 1" PVC connectors in each of the bulkheads next to the long 1/2" PVC - center (bulkhead between fuel tanks) and aft (both are shown). There is no forward one - the fuel compartment does not directly connect to the forward bilge.




The long pipe connecting the forward bilge to the aft bilge bypasses the fuel compartment. Debris in the forward compartment can block this 1/2" pipe which is under a piece of wood that the shower sump sits on. Difficult to see it. It was also plugged in aft bilge. GW may have decided to isolate forward and aft bilges and plugged mine (it's removable).

.

There is no plug in the 1" PVC feed thru's (plastic limber holes??). Water can flow from the aft bilge forward under the fuel tanks and back to the aft bilge. It would also allow a leaking fuel tank to put fuel in the aft bilge.



I would like the forward bilge to dry out and drain back. I'll have to see if that really happens when the boat is in the water.

 

[Gmack76]

In general, the forward bilge should not drain into the tank coffin There may be a continuous drain tube that passes under the tank or there may be separate tube to one side of the tank stringer.

Either tube cab get plugged up. It also can be easier to find the aft end of the tube and snake forwards as opposed to snaking from the mid section aft.

Note that on many Grady hulls and other makes too, the mid bilge will often have standing water since the mid bilge section may sit lower than the aft bilge.
The only sure way in that case to see if the bilge is draining correctly to to raise the bow so that the keel is slopped aft. Water in the mid bilge should flow to the aft bilge. If it doesn't and the mid bilge gets a significant amount of water (deep that is) then your drain tube or tubes are probably blocked

Thank you. I did end up snaking this afternoon from the aft bilge forward and didn't find any obstructions. Your point about water tending to sit in the forward bilge because it sits lower than the aft bilge is well taken and that may be all I'm dealing with.

 

[Gmack76]

I replaced my fuel tanks on my Islander this Summer. Still finishing up. Your question about how the forward, fuel compartment and aft bilge are managed is one that bugged me for a long time. A Islander is a little brother to a Sailfish. Other than the beam the boats are pretty much the same.

That 1/2" pipe should be snaked from the aft bilge (remove small aft deck) to the front bilge. Then clean the complete forward bilge and vacuum up the debris you can get out. It's too hard to do from the forward end. You will be trying to push the blockage all the way thru to the aft bilge and may wedge it in there. Don't ask me how I know that!

This is from my post on the tank replacement whit a few updates:

Next is to investigate the amount of water in the fuel compartment and how the drains should be working. The boat has a long 1/2" PVC pipe from the forward bilge to the aft bilge. There are 2 - 1" PVC connectors in each of the bulkheads next to the long 1/2" PVC - center (bulkhead between fuel tanks) and aft (only aft one shown). There is no forward one - the fuel compartment does not directly connect to the forward bilge.

View attachment 31743


The long pipe connecting the forward bilge to the aft bilge bypasses the fuel compartment. Debris in the forward compartment can block this 1/2" pipe which is under a piece of wood that the shower sump sits on. Difficult to see it. It was also plugged in aft bilge. GW may have decided to isolate forward and aft bilges and plugged mine (it's removable).

.

There is no plug in the 1" PVC feed thru's (plastic limber holes??). Water can flow from the aft bilge forward under the fuel tanks and back to the aft bilge. It would also allow a leaking fuel tank to put fuel in the aft bilge.

View attachment 31745

I would like the forward bilge to dry out and drain back. I'll have to see if that really happens when the boat is in the water.

Thank you. This is very interesting and took several readings for me to wrap my mind around. So, if I removed the two deck plates would those 1" pvc connectors in the bulkheads be visible/accessible or would the tank obstruct them?

 

[Hookup1]

Thank you. This is very interesting and took several readings for me to wrap my mind around. So, if I removed the two deck plates would those 1" pvc connectors in the bulkheads be visible/accessible or would the tank obstruct them?

You can't see them with the tanks in place. You can snake the aft one - it's only 1 1/2" long. Hitting the one between the forward and aft tank is near impossible. I have used endoscope cameras but they are impossible to control and difficult to see. You are probable ok there. To even have a chance you have to pull the whole deck.

 

[Gmack76]

You can't see them with the tanks in place. You can snake the aft one - it's only 1 1/2" long. Hitting the one between the forward and aft tank is near impossible. I have used endoscope cameras but they are impossible to control and difficult to see. You are probable ok there. To even have a chance you have to pull the whole deck.

10-4. Thanks. I had the deck plates off last year just to get a look at the tanks. I should have poked around a little more when they were off.

 

[Hookup1]

10-4. Thanks. I had the deck plates off last year just to get a look at the tanks. I should have poked around a little more when they were off.

Not much to see. The tank shim blocks on the aft end of the tank are 1 1/2". You could get a camera down there to see the drain but the deck has to be up. The access ports are over the sending units. Same for both tanks.

One thing I was concerned about was freeze damage to the 1/2" PVC from the forward to aft bilge. It is not winterized. Fortunately mine was ok.

 

[Gmack76]

Just to update . . . It turns out I did not have a blockage; I just wasn't getting the bow high enough for all the water to drain back. Boat is on land now. This evening I pointed the trailer tongue basically at the sky. With the external drain plug removed, all that water from the forward bilge finally ended up aft and then drained out the back.

A few times this season while on the water I did attempt to run with the bow way up for a short period while manually running the aft bilge pump. I was trying to force the water astern and then pump it out with the bilge pump. Either I wasn't creating enough of an angle to get the water astern or my bilge pump wasn't pumping it all out. I'll replace that one this off-season.