Has anyone added a second bilge pump in the stern? Seems a bit tight. Also, finding somewhere to route a new hose to a thru-hull fitting also seems challenging. I really would like to have a second "high water" bilge pump in the stern.
Adding an Additional (emergency) Bilge Pump in the Stern - 2006 Marlin
- Thread starter Ralph163
- Start date
Ralph, I added a second stern pump myself just last summer as a backup. I'm sure my 20 ft. overnighter might be a little bit easier than a marlin but I'm sure once you get into it you will find a way to get things through from the pump to the hull . You should add another thru hull just for the new pump. Adding a second pump, you might think about raising it up about a couple inches higher than you main pump so that they are not running together all the time. You would only want to run it in a emergency situation. I added a separate dedicated switch and also a direct full time power to it through a electronics sensor.. The hardest part is getting head and arms in there to work . It can be tough. I added a couple pics of mine for reference. I raised mine up 1.5 inches above the main pump. There are so many different pumps out there so pick one that suites your needs and go at it.
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Yes, that's exactly what I need to do. I just can't find the room, especially to route the thru-hull line. I spend nights offshore. So I really need the backup pump.
Do you have room to run the new hose a few inches left/right/above/below the existing thru-hull?
Keep in mind that only the float switch for the pump needs to be mounted higher (an L-bracket to the stringer would work... and it doesn't need to be close to the pump). It looks like you might have room forward of the existing float switch for the new pump? Or put the new pump where the current switch is?
Another option "could be" a portable pump. Put it on a weighted board and drop it into place and use alligator clips to a battery. You would use the "automatically goes on while you're sleeping function", of course.
A high water alarm would be very easy to install and would provide the sleeping "comfort"
Keep in mind that only the float switch for the pump needs to be mounted higher (an L-bracket to the stringer would work... and it doesn't need to be close to the pump). It looks like you might have room forward of the existing float switch for the new pump? Or put the new pump where the current switch is?
Another option "could be" a portable pump. Put it on a weighted board and drop it into place and use alligator clips to a battery. You would use the "automatically goes on while you're sleeping function", of course.
A high water alarm would be very easy to install and would provide the sleeping "comfort"
Ok looking at yr pics it seems kind of tight . Might be able to fit just to the right side of existing pump with the use of a 45 deg. elbow with isn't too bad though straight out from pump is more desirable. I raised mine about 1.5 in on a epoxy enclosed block that I epoxied to the floor. Been there since last summer and it hasn't moved . I didn't want to make any holes in the bilge floor. If the floor is flat enough on the left side of the original pump, it might fit there and you could go straight out of the pump and follow the original pump hose out if there is room enough. Also you might think about adding a water sensor alarm while you are going to sleep overnight. I also added one on mine and you can see the switch and alarm in the pics I added. That is the black flat sensor on the wall in my bilge. It's loud enough to wake you for sure. Looks to me though that there is enough room ,though tight, for a second pump.
I second what Dennis just said about mounting the switch higher than the pump. Any height above original that you prefer. I mounted mine on the pump itself so I raised pump with it but if you have a separate switch you could raise just the switch.
When adding a backup bilge pump. Do you also add another bilge hose and separate discharge port through the hull? Or can you use the same discharge hose as the primary? I guess it makes sense to have each bilge pump with there own independent discharge hose? My thoughts are avoiding drilling another hole through the side of the boat.
You MUST install a new, dedicated hose. Otherwise you will lose GPM flow rate. A new hole is no big deal - easy to do and very common place.
Regardless of science, most likely (ideally) the e-pump will be larger and use a large diameter hose, as well.
Yes. I have installed secondary bilge pumps before. I mount the pump low, and the switch 3 inches higher. I know some people like to mount the pump higher as well, believing that keeping it dry preserves it. But that's not my issue.
I need to find a location to mount the pump. Where the existing switch is might inter fear with the seacocks and the rods that control them. I can mount off to the right. I would need to 5200 a small piece of azec. The pump won't be level, not that that would matter tho. The hardest part is finding a location to route 1 1//2 water discharge hose. It's VERY tight down there, What you see all the way to the left is a stringer, not the hull side. You need to pop your head inside a Marlin bilge to see how tight it is.
I need to find a location to mount the pump. Where the existing switch is might inter fear with the seacocks and the rods that control them. I can mount off to the right. I would need to 5200 a small piece of azec. The pump won't be level, not that that would matter tho. The hardest part is finding a location to route 1 1//2 water discharge hose. It's VERY tight down there, What you see all the way to the left is a stringer, not the hull side. You need to pop your head inside a Marlin bilge to see how tight it is.
Azec is PVC, right? If not, you can get PVC board at HD relatively cheap in the trim board section. You can glue two or three pieces together and then match the angle of your hull with the table saw.
I agree - there's no reason to keep dry and out of the water - it will be totally fine.
Would it be easier to drill a hole through your stringer? Oversize it by 3/8" to 1/2" and fill with epoxy. Use tape on the backside of the hole and again on the front, creating an open spot at the top (higher than the hole) to pour into. Then re-drill your properly sized hole. The stringer wood will be totally encased in plastic - not just the visible part, but the epoxy would have soaked into the wood. Because of the soaking aspect, you will need to fill the cavity at least twice, maybe three times. Just keep an eye on the level and refill before it starts to kick. Once it starts to kick, it's going to go fast because there's a large volume for the area.
I agree - there's no reason to keep dry and out of the water - it will be totally fine.
Would it be easier to drill a hole through your stringer? Oversize it by 3/8" to 1/2" and fill with epoxy. Use tape on the backside of the hole and again on the front, creating an open spot at the top (higher than the hole) to pour into. Then re-drill your properly sized hole. The stringer wood will be totally encased in plastic - not just the visible part, but the epoxy would have soaked into the wood. Because of the soaking aspect, you will need to fill the cavity at least twice, maybe three times. Just keep an eye on the level and refill before it starts to kick. Once it starts to kick, it's going to go fast because there's a large volume for the area.
That Atwood 1700 is pretty hefty, with 1 1/8 inch hose. You must be going with something like a Rule 3700, to be using inch and a half discharge hose. Looks like you have room, so I’m guessing that the access is difficult. How do you service the FP generator?
It's a pretty tricky run. Not as simple as going through a single stringer, it's zig zag and needs to pass through a compartment or two. Of course I would seal any holes I drill, especially through a structural element.
Fishtales
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First thing I'd do is change the original pump. That's been there for years, a proactive change is a good thing. Second, there isn't another mounting block, so you'd have to either use adhesive for the base or install a block and glass over it so you can screw the pump down. Might be better to swap the front pump out with a larger capacity model and have 2 new pumps in the boat. Water is going to settle up front when you are at the dock, slip or on the mooring. I'd rather have 2 new high capacity pumps (what I did) vs 3 with one being new.
I was looking at the Rule 2000 GPH as my backup. So far, I had the boat 1.5 years. Haven't serviced the gen. Replaced a starter and a relay myself. Yard just did the oil change. This year I will probably try and crawl behind and look at servicing, air filter, impeller, etc. I am debating whether to service the impeller now, or wait until it fails. Seems to be good right now. I am afraid I could damage if I wait till it fails. But I also don't like to be overly proactive, fixing something that isn't broke. It's tight back there, but you can squeeze behind if your skinny and lay something down.
Absolutely, but I would like a way to pump the water out if it's high. Either way, an alarm goes in.
If you are looking at Rule 2000, that's 1 1/8 discharge hose, not 1 1/2, which will be a lot more flexible, and easier to route. Look at where your 1 1/2 gen hose crosses your 1 1/8 bilge hose. The gen hose is closer to the camera, but still...
Harrysea
Well-Known Member
As a Marlin owner, I can say that I’ve never had water at the stern where the rear pump could get it. Any bilge water I accumulate always ends up where the forward bilge pump takes care of it. I keep my boat on a lift with the bow elevated and stern bilge stays dry. If I worried about taking on water offshore, I’d be more likely to install a second pump forward since that’s where the water gravitates.
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I added a 2000GPH rule to the rear bilge area in my 270. I put it on bracket that's 1" off the floor. its wired to the unswitched side of the house battery, (always on) with its own dedicated float switch. I ran the hose to the port side with the other thru hull discharges. it also powers a high water alarm at the helm. I mounted it low so it will warn me that the two other pumps are not keeping up and I have a serious problem. mounting it higher just delays the warning