There is no need to take the cap off the top, all you need to do is drill a small 4-5mm hole just below we’re the handle pokes out, no need for welding, this hole can be used to lube your pump as well , I use a bottle from when the wife dyes her hair, the bottle has a nice point , ideal.
If the seal is good on your pump you shouldn't be getting any water in the top part of the pump, I have an original Alvey pump and never had a problem with water getting above the seal, except on purpose to flush and clean.
🎣 i have an Alvey steel bait suction pump and a blue pvc plastic pump. I make my own washer systems to put in them which gives my pumps Much better suction power than what they had! No need to take the metal cap - lid off! It keeps the sand and water out. The water, sand and mud gets in Below my washers. I suck up some clean salt water when finished pumping and some fresh water at home to clean the inside of pipe! 🦐 🎣
I make silicon washers for my pump…I find it easier to mix some soap and water and squirt the silicon into the soapy water,then put my hands into the soapy water and mould the silicon into a ball(it will not stick to your hands👍)…then put a bit of soapy water on my glass and in my washer/gasket mould and press the amount of slicing I need into mould by hand and flatten off with a plastic trowel(and soapy water)…as well as preventing sticking and mess the soapy water also helps speed up curing of the silicon you can pop 22mm washers/gaskets out of the moulds in 3-4 hours and they’re usually fully cured and ready to use in 4-5 days👍 another tip that might help is get rid of the wing nut(they tend to turn and constantly adjust the suction each time they make contact with the sand) replace it with a nylon assisted lock nut👍 other than that great video👍👍👍
Thanks for your detailed instructions bud, I just finished modifying my pump. It improved the suction a lot. I didn't have a welder so I used Pratley Steel to secure the handle. This video was a great help. Tested it on a bucket of water. Works great. 👍🤗.