06-16-2018, 12:26 AM
Fuel pumps seem simple at first.
but are not. ( many failure modes, and stated above by me)
what is simple is that it runs on 12vdc, it will run all day on 12vdc, just like the blower in the cab will.
The pump however , is fuel cooled, and fuel lubricated, and is not a water pump. (in fact most pumps do not like running dry ever, as s general rule)
The pump if connected to say a 12vdc battery directly will wreck the impeller, un less you keep its (sock) submerged in FUEL.
the 3 seconds is inside the ECU , and NO WHERE ELSE.
you can in fact
bench test any pump (ask how)
or tank on the floor, with a portable battery 12vdc or you can use the stock harness and see and hear the pump work for 3 second each key on.
the pump is just an electric motor , that runs a fuel impeller pump device. all in one.
3 second rules of for CRASH SAFETY,.
and is LAW. (DOT laws) (if a driver hits a tree , do you want the pump running and causes a huge fuel fire, killing every one there, for sure in car or near, or even the fireman? no)
understanding purposes makes the why more easy to understand and remember , ok?
the pump can be tested , 3 ways,
on the car tests
tank on ground
pump on bench
3 ways.
it's just DC motor, (but the impeller must not be damaged testing it)
but are not. ( many failure modes, and stated above by me)
what is simple is that it runs on 12vdc, it will run all day on 12vdc, just like the blower in the cab will.
The pump however , is fuel cooled, and fuel lubricated, and is not a water pump. (in fact most pumps do not like running dry ever, as s general rule)
The pump if connected to say a 12vdc battery directly will wreck the impeller, un less you keep its (sock) submerged in FUEL.
the 3 seconds is inside the ECU , and NO WHERE ELSE.
you can in fact
bench test any pump (ask how)
or tank on the floor, with a portable battery 12vdc or you can use the stock harness and see and hear the pump work for 3 second each key on.
the pump is just an electric motor , that runs a fuel impeller pump device. all in one.
3 second rules of for CRASH SAFETY,.
and is LAW. (DOT laws) (if a driver hits a tree , do you want the pump running and causes a huge fuel fire, killing every one there, for sure in car or near, or even the fireman? no)
understanding purposes makes the why more easy to understand and remember , ok?
the pump can be tested , 3 ways,
on the car tests
tank on ground
pump on bench
3 ways.
it's just DC motor, (but the impeller must not be damaged testing it)
http://www.fixkick.com