Plumbing for flushing or trailer running.
 

I'm wanting to plumb my boat so I can run engines from time to time from the garden hose on trailer. My water pickups/screens are on the bottom of the haul and hooked directly to the sea pumps. I thought about mounting an 1 1/4" gate valve to the stringer and have a t fitting that's 1 1/4" x 1 1/4" x 1/2". The same ones used for water pressure relief valves etc. and then mount the flush on ea side in desirable location.

Would it be best to plumb in another 1/2" gate valve under flush hook up in which case the cap ever come loose so I don't suck air and melt impeller. I do not want to use the plunger muffs and would like to plumb something. Out of all the boats I've owned over the years only one had a flush on it and it was years ago and don't recall much about it.

Tks in advance for your input.
John

Flush

I just got thinking if an 1 1/4" 3-way ball valve would work here and eliminate the t-fitting and other valve.

Any thoughts on this idea?

I just have a tee right before my seawater pump, with the flush hose (stiff walled) going to the hose adapter you posted above mounted at a convienent location, no valves anywhere, or anything. You are correct though, gotta make sure the cap is tight. I forgot to tighten mine up and notice my WP gauge bouncing up/down as it sucked water, then air, then water,...... Considered a valve at the hose adapter, but decided to just make sure the cap is tight instead is easier. :)

Tks for the reply. So in a nutshell the sea pump has enough suction so water doesn't tend to head back down the pickup. I suppose like you mentioned installing the tee nearest the pump the better. Makes complete sense. Much better than buying the 3-way SS ball valves I was close to buying. Pricey but nice however it's only for occasional use.

Tks
John

Yes. When I 1st turn the water on, it will flow out the drive, which is nice if you wanna back flush. But as soon as the motors are started the SW pumps will prevail and suck the water their direction. I just turn water on full and never a hiccup