Hose from shower pan collapses when pump turned on

[jclester]

So, I’ve refit the head with a shower, pump, lines etc. The only thing I used from the original boat was the hose from the shower pan to the sump pump. The pump is a 3.0 gpm and the pan is too shallow to have an integrated sump and pan. Every time I turn on the pump the original hose collapses and very little water can flow through. Before I tear up everything (almost) I’ve done I’m looking for suggestions.

Right now I’m looking at removing the “one way valve” (can remember the correct name) but I know it’s in correctly or I shouldn’t get any suction through it.

I’m thinking about trying to run a smaller tube (copper) through the shower pan up to the valve in the hopes of reinforcing the original hose. I’m guessing I won’t be able to get past the bend but I really don’t want to deconstruct everything.

Thanks

[DeepFrz]

Try a smaller pump or replace the hose with one that wont collapse.

[a64pilot]

You most probably have a partial clog somewhere that is restricting flow enough so that the hose gets sucked flat.
Take a garden hose and try to blow through the hose backwards. I assume only one end is accessible? If not then blow through the normal way.
If you have to do it backwards, put a towel on the drain so you don’t blow nasty water everywhere.
I’m thinking a hair/soap scum clog.
Usually the pump doesn’t connect directly, usually use I believe is to drain to a bucket and have the pump in that bucket.
Mine is a diaphragm pump, those can be mounted up high, out of the bucket so it’s easy to get to for service.
Be sure to have a strainer before the pump.