Our Politics here to help understand “Squeeze Bulb Priming”. For sure, I have been using Squeeze Bulbs with diesel fuel for well over 20 years now. I still have not seen one rot or fail externally, so to me they have withstood the test of time in the field. I still get feedback from those who do not have any experience with them worrying about “this and that”. All I can say is they are used and approved with gasoline in all types of applications, so to me, they must be safe, regardless if ABYC or some surveyor has an issue with them. If I worried about those things, I just as well quick thinking for myself and go back 20+ years in my work.
As to flow and restriction: If you use the typical 3/8″ variety squeeze bulb, you can install them in series ( if you like, with no valves or “T’s”) and not worry about any undo restriction on most mechanical diesels up to 250 HP or so with rotary type fuel injections. On engines with inline or CR “Bosch or Nippon Denso” type fuel systems, I’d use either a single semi-isolated system or a fully isolated system and 1/2″ – 5/8″ line for the main fuel system as much as possible. With the fully isolated system, you can feel 100% comfortable even using 3/8″ clear vinyl hose for fuel line so you can “see” the bulb do its job. Also, when testing fo air, you can allow all the fuel to go through the clear hose an see if you are sucking air someplace before the bulb.
Simple Multi-stage Fueltration System with Squeeze Bulb Priming
Nothing I have used does a simpler or better job than the old fashioned and simple “Squeeze Bulb” as to priming the system or using it as a tool to check for other fuel system problems. I’d love to see a 1/2″ ID unit, but I have not found one yet…
For those who are squeamish about using clear vinyl tubing for this part of the system (Because “no one” has approved it) please feel free to substitute CG A-1 fuel line for the squeeze bulb hoses.