Did my shower pump just blow up?

[Liquidmx]

Today I fired the bu, planning on checking out my shower mod and others as well. Everything went well until I fired up the shower. When I pushed the switch it came on like normal with the famous loud motor sound and pushed out a nice bit of water. It then surged and became quiet. I put my hand on the pump and it was running (spinning) but not nearly as loud as it has historically been on my boat (or other boats with showers). So my next step was to pull the pump apart assuming I shredded the impeller. I take the thing apart and there isnt an impeller at all! Its a two plunger system, wtf? I have no clue how to diagnose this type of pump and whether or not its working properly. Some may remember I modded my hot water source to the heater line rather than the engine drain line. However my cold water source did not change at all. Is anyone else running this plunger motor with success? Has it been around a while? And would it be wise to swap it out with a regular impeller sort?

Thanks,

Matt Winans

Edit: Ahh I think I will put it back together an pull the pump line from the control valve, put it in a bucket o water and see what happens. Regardless I am curious to see what other people's experience is with this type of pump.

[uk_exile]

Mine died with similar sound and effect. Was going then just stopped. Pulled it apart & the motor was burnt out. There is a wobbler type arrnagement between the motor shaft and the plungers (made using a bearing and a offset spacer) & it seems my bearing had near seized causing the motor to overload, over heat and burn the windings. Investigated a motor rewind and was cheaper to buy whole new pump from an RV / camping supplies store.

[Liquidmx]

A quick update:

Tested the pump by putting pickup line into a bucket of water, picked up water just fine. So I assumed the valve must have a clog somewhere (as hot was non-existent and cold was sputtering). Pulled cold off to find a small amount of water in the line, however the hot line was packed full of water, almost pressurized. The valving was completely clean without any trace of blockage. I am totally baffled as to why the shower was barely sputtering water. I am hoping some freak priming issue is the reason. Anyways I re-assembled the system and plan on "water testing" soon. The only other possible scenario is that the cold line is bypassing the pump into the heater line due to a vacuum of sorts? Anyways I will update this post with a water test soon hopefully.

[pup]

The supply to the pump probably had an air pocket. Close both faucets on the control panel. Remove the supply line to the pump & run the engine. Open the cold faucet & let it run until water comes out. Close the cold & open the hot also until water comes out. Now the system should be free of air. This will probably work better on the lake instead of running the boat on a garden hose.

[Liquidmx]

Yah, thats what i was thinking pup. Does anyone run a check valve on those lines to keep them primed?

[pup]

The system shouldn't need check valves as both hot & cold lines are under pressure from the engine. If your problem occured when running the boat on a garden hose, the hose may not have been providing enough water to keep everything full. If it happens again when on the water try bringing the rpm's up to about 1000. At 1000 the pump pressure is higher & should push the air through the shower pump.