Jabsco bilge pump, pumps intermittently

[Bobg]

My bilge pump isn't very  reliable this year, seems like I have to activate the float switch a few times before the pump pumps, It runs every time I activate the switch, just doesn't pump, and when it does pump, it pumps a real healthy stream.  I have removed it from the base to check it, there doesn't seem to be any debri involved. I have no check valve in the line.  I did access the archives, and found a similar problem  back in 2001 but no replies.  Any ideas? New Pump? appreciate any ides before I buy.  Thank you  Bob

[jmnpe]

Hi Bob,

In my experience in several boats, this is actually a fairly common occurrence. Buying a new pump isn't really a good longer term solution, IMHO. It generally happens when the bilge water level has been well below the bilge switch activation level for a while, and then the water level rises again slowly. I have not done any scientifically acceptable study on the matter, but it seems that there are times when the pump seems to experience an airlock-like condition. I have made the pump start pumping again by (1) repeated cycling of the bilge manual or float switch; (2) popping the bilge pump loose from the snap-down mount and tilting the pump momentarily to one side; or (3) sloshing water around into the intake of the pump. In every episode, the is nothing wrong with the pump once it begins to pull water into the pump, and until that occurs it simply runs "free" at a higher speed. As an added observation, I have never had the problem occur if there is a significant "head" of water depth in the bilge: only with less than 3 to 4 inches of water. ( I guess that's the good news  )

I have noticed it more often with the bilge water has slimy junk in it, or other stuff floating around down near the pump, and only after the pump has been in place for several years or more. This has reinforced my unconfirmed hypothesis that "stuff" in the water creates a "bell jar" effect by clogging up the "trash screen" around the intake area of the pump.

Anybody else have any additional thoughts?

John

[Bobg]

Thank you John, I do believe you are right on, as I do get it working by doing some of the things you mention, will hold off on a new pump for now and monitor it a little closer, maybe fill the bilge with a garden hose and seeing the results, Thanks again Bob

[SeaFever]

Hi Bob,

Rather than fill the bilge with a garden hose, I would suggest removing the pump and placing/holding it in a bucket that half (or less) full of water. If the pump has a inbuilt switch lower the pump into the bucket till it works. If the float switch is outside, operate the same and have the pump recycle the water in the bucket for s little while. That will allow you to do what you want without puring all that water in your bilge. Just an idea.

In my case, I had a Rule 1100 pump that has a built in switch. The pump started working intermittently so I opened it up and cleaned the float cylinder properly and it has been behaving since. The reason for the sticking was that some oil had leaked from my pressure sender into the bilge and that was making the float switch stick. That was my root cause, yours may be slightly different.