Bilgepump Backwash

[userreflex]

I just replaced a small very loud diaphram pump with a 1000 gph centrifugal pump. However, I now get a large amount of backwash and as a result the bilgepump is constantly cycling. I know it shouldn't do that.

My boat is a Beneteau First 325 with a small bilge sump. I have a float switch attached to the pump. The hose runs to the stern, so it is probably 15-20 feet long. I used the existing hose from the old pump which was mounted in the engine compartment, about 6 feet aft of the sump. It has a slight loop there.

Any suggestions?

Userreflex

[TrueBlue]

Perhaps you could detach the float switch from the pump base and mount it slightly higher than the pump. You will have some standing water left, but this is to be expected. At least the pump will not cycle constantly.

[Cruisingdad]

Just put in a check valve: http://www.defender.com/product.jsp?path=-1|51|106370|316448|315123|567965&id=741017 or http://shop.sailnet.com/advanced_sea...ds=check+valve

Very easy install. Only issue is that they can get clogged - but I have one on my pump (not this one, but somewhat similar). Cheap, easy, done. If you are a cruiser, carry two or leave enough slack that you can remove it if it fails offshore. I have had mine clog once and the pump will not move the water.

- CD

[T34C]

Add a second much smaller pump that sits in the bottom of the bilge and uses a smaller id hose to a seperate thru hull (maybe closer if you can). Then mount your larger pump slightly higher in the bilge. The small pump will do a better job removing small amounts of water that collect in the bilge, will have less back flow and you will still have the big pump in case something breaks and you start having real water trouble.

[TrueBlue]

CD,
Unless you have a high water alarm, before you know if the check valve fails, couldn't it be too late? Personally, I don't think I'd be comfortable having anything obstructing water flow in an automatic bilge pump drain hose.

[Cruisingdad]

TB,

You want my opinion on high water alarms??? I don't understand why they are not MANDATED on every boat... and not just an alarm, but a second bilgem pump set to go off with the alarm.

However, since the mid 90's, I have had a clog one time - and then it was on a new boat (probably sucked up some trash). Since then, nothing. THat does not mean it cannot happen again, but I can tell you that I have sucked up and passed trash even through the check valve.

To answer your question, I don't think it is a problem. My opinion and experience.

- CD

[TrueBlue]

Just asking a legitimate question CD - didn't mean to get your BP up.

We have two automatic pumps as well, with an alarm on the higher float switch.

[Cruisingdad]

Sorry TB... You did not bother me at all!!! Sorry if it read that way. You know me!! I am the easiest, least offendable, best looking, finest yacht person on this forum! I know you agree!!

THat is the issue with writing a thread or email, you cannot inflect tone. Sorry if it sounded otherwise. You know me... I have gotten ticked about twice on this forum in 12 months, and I GUARANTEE YOU THE RECEIVER KNEW IT!!! HAHA!!

Now, "GO PUT A CHECK VALVE ON YOUR BOAT AND LEAVE ME ALONE TO CONTINUE READING THE REPUBLICAN DEMOCRAT THREAD!" I keep reading and re-reading what Sailaway writes and still do not understand it. It looks like English, spells like english, but doesn't read like english. Very much like his other posts. HAHA! (You know he will give me a hard time for that).

HAHAHAH!!

- CD

[Gary M]

I have the same back flow problem with a small electric pump. I only run it on manual and open the valve when it is in use. The old hose that I replaced had a high loop, well above the water line and a badly corroded bronze thingy that I assume was a siphon breaker. Anyone have one of those and is that what it was ??

I assume the check valve would stop the back flow and also be a siphon breaker, especially given my manual only operation. I do understand why an automatic pump is a good idea but I only have 3 through hulls below the water line and they are closed when ever I am not on the boat. I check the boat virtually every day.

Gary

[TrueBlue]

I do understand why an automatic pump is a good idea but I only have 3 through hulls below the water line and they are closed when ever I am not on the boat.

Hmmm . . . unless your boat has an outboard, did you forget about that big hole the prop shaft goes through, and on some boats the rudder post? It's common for these penetrations to contribute small amounts to the bilge water level - allowing even greater amounts of water in, if seals give way.