I got these to pinch the coolant hose and none of them helped. They aren't tight enough to prevent fluid from spilling all over the motor, but I think it slows it down. They may work for some but not for me.
Joywayus 5/8" ID Hose Barb Hex Union Brass Fitting Water/Fuel/Air With 10 Stainless Steel Clamps (Pack Of 5)
13 Review
DIGITEN DC 12V 1/4" Inlet Feed Water Solenoid Valve Quick Connect N/C Normally Closed No Water Pressure
14 Review
12V Brass Solenoid Valve, 3/4" Electric Air Valve For Water, Air, Gas, Fuel And Oil - Normally Closed By Beduan
10 Review
1 Inch Beduan Brass Electric Solenoid Valve, 12V Normally Closed Air Valve For Water, Gas, Fuel, And Oil
10 Review