diesel pump question?bx 1.9

ssray · Unread post by **ssray** » 13 Aug 2005, 16:25

how much diesel will my pump send back to the tank? i`m in the process of doing a diy veg conversion and need to know if i can run the return just back to the diesel tank, in wich case i can get away with one solinoid valve

citronut · Unread post by **citronut** » 13 Aug 2005, 16:49

if you dont send it back to the tank where would you send it??,i think it would be ilegal to pump it on to the road
regards malcolm

ssray · Unread post by **ssray** » 13 Aug 2005, 17:27

in theory i should send the veg back to the veg tank and diesel to the diesel tank, but as i`m running 75% veg in my main tank i thought as long as its not too much of a mix, so i need to know what kind of percentage is returned by the IP.
regds ray

Kowalski · Unread post by **Kowalski** » 13 Aug 2005, 19:16

In a normal diesel system, the fuel in the tank is circulated and heated to stop it waxing, so a LOT more is pumped about than is actually used, the return hose from the fuel pump is the same diameter as the suction hose.

rotodiesel · Unread post by **rotodiesel** » 13 Aug 2005, 19:58

Difficult to generalise, as it depends on fuel injection equipment, installation and engine operating regime, but the fuel volume returned can be in excess of 80% of the total flow at low engine fuel demand and high revs. Make sure you keep the back pressure on the return line to reasonable limits, and watch the lubricity of any brew you choose to burn. The engine won't mind too much as long as you keep the cetane rating high enough to prevent detonation, but the pump will suffer if you get it wrong.
rotodiesel.

oilyspanner · Unread post by **oilyspanner** » 14 Aug 2005, 14:26

I use the return system to drain the fuel from scrappers, ten minutes idling lets a good gallon flow through the return line approximately, you should let the diesel return to the diesel tank and the vegoil return to its own otherwise you might as well only have one tank.
Stewart