Can't prime out of forward fresh water tank

[esp803]

Hello all,

This forum was incredibly useful for my starter issue, so I figured I'd give it a go for the water system.

The boat is a 1981 Catalina 30, and the fresh water system is currently rigged as a small tank under the port side seat and then a much larger tank under the forward v-berth. The boat is relatively new to me. The two water lines from the tanks join in a t junction under the aft berth prior to going to the electric water pump. I accidentally ran the system dry a month ago, and filled both tanks via the tanks themselves (opening on top) as I wasn't sure how the outside fillers were plumbed. About 2 weeks later I ran out of water (about 6 times faster than I was expecting). It seems that the side tank was dry and the forward tank was still full. So, I refilled the side tank, and happily had water for another two weeks. It primes and pressures very well when pumping with a faucet open from the side tank. Just not the front tank.

Today, I've got some time and I'm trying to sort out how to get the water flowing from the front tank. The line attaches to the bottom of the tank through a plastic valve, the valve is open however it doesn't seem like water is freely entering the line... I would take the valve off, but unfortunately the tank is full.

Just looking for suggestions at this point. Thank you all for your help!

E

[jamhass]

Air leak between the forward tank and the select valve.

[jeepbluetj]

That's the typical way C-30s were plumbed with two tanks. (My second tank was removed somewhere along the line).

Just pull the hose off of the forward tank - the bottom of the tank, the valve, the hose, or the T fitting is plugged. So 25 gal of fresh water ends up in your bilge? Nice rinse and test of your bilge pump.

T fitting must be below the outlets of both tanks, or the pump will suck air from the empty tank. Usually the fwd tank will kinda fill the one under the stbd settee back up as it's a bit higher in the boat.

[MarkSF]

How are the two tanks vented? My Bristol has a similar arrangement, with vents on both tanks, consisting of a loop placed higher than the tank. If a vent is blocked, that can also cause problems with one tank draining into the other.

[OS2Dude]

I had exactly the same issue with our 1985 C-30 mkI. The hose from the forward tank makes a hard bend to run down the starboard side under the starboard tank to join at the 'T' fitting under the aft quarter berth.

After MUCH fretting about, I finally discovered the hose had crimped at the corner, effectively closing the hose. I pulled on it a while and it eventually shifted, then the water started to flow. Don't know if it was pinched that hard, or the gunkiness of old vinyl had 'glued' it or what held it in place that hard but the water does flow now.

You should have two fresh water deck fills on the starboard side by the chain plates. One fill for each tank.

Fair Sailing

[zeehag]

check system back pump to tank and take with you a screwdriver or wrench for hose clamps..mebbe anew hose.... sounds like there is a system fail upstream from pump. good luck

[topmast]

Cheap plastic valves can be over tightened,torque off the shaft and never open again.