SU fuel pump coil [?] testing...???

[timbn2]

Im not an electronics genious so bear with me... This is the main body of my recently purchased SU fuel pump that i am re-doing. Is there a way to "test" this to see if it is good? Is this something that can even go "bad"?
thanks
tim

 

[Dave Russell]

You could measure the resistance of the coil, between the two leads shown. A good 12 volt coil should read around 3 ohms. A GOOD Ohmmeter is needed. A poor meter may not be able to accurately read very low ohms such as this. If the reading is much higher or lower the coil may be defective. A low reading could mean shorted turns, a high reading would mean an open circuit or break in the wires.

Measure the resistance between the leads & the pump frame. It should show very high resistance. If not, the winding might be shorted to ground internally.
D

 

[timbn2]

i'm getting between 3.4 and 3.8, usualy closer to 3.8.

 

[Dave Russell]

Sounds great. It isn't shorted & isn't open circuited. Really nothing more to do with this part of the pump.
D

 

[timbn2]

thank you for the info so far...
one more question...
was there ever a "drain" hole in the body...like this

it looks to clean to be corrosion, but ...???????? i know the one on the bottom left is meant to be there but what about the centered one?

 

[Keoke]

Yep What about the centered one ?. Never seen one like that it must be as old as Muthusalim. what is the one on the left for?---Keoke

 

[Dave Russell]

thank you for the info so far...
one more question...
was there ever a "drain" hole in the body...like this

it looks to clean to be corrosion, but ...???????? i know the one on the bottom left is meant to be there but what about the centered one?

I can't say for sure. Different models had different holes. The one in the enclosed pic has a small air inlet, hose fitting in the lower part for ventilation. It works in conjunction with the fitting on the top left which is a vent with a ball check valve in it.

When the pump is operating, air is pumped through the pump to ventilate the contacts. Without some ventilation, the slight contact arcing would cause ionized air to build up around the contacts & increase contact burning. The air inlet is sometimes led to a drier location via small hose so that water does not get into the pump.

I guess on your pump it depends on exactly where the "holes" lead to. In any event, the pump internals need some ventilation.
D

 

[Keoke]

Hi Dave,yep after locating the ground connector hole and looking at the original picture that is one of the first stepped end cap pumps. There is no vent in the cap and that center vent must be positioned so it points straight up when the assembled pump is in its correct mounting position. I hope he marked the two halves of the pump before he separated them.This pump should also have the 11 brass armature bearings in it too.---Keoke

 

[timbn2]

Hi Dave,yep after locating the ground connector hole and looking at the original picture that is one of the first stepped end cap pumps. There is no vent in the cap and that center vent must be positioned so it points straight up when the assembled pump is in its correct mounting position. I hope he marked the two halves of the pump before he separated them.This pump should also have the 11 brass armature bearings in it too.---Keoke

Yep...it has the stepped end cap w/o vent and it also has the 11 brass bearings...
why would the center hole in question need to be oriented upward when mounted? - Tim

also... Moss has the stepped cap listed for replacement pumps ant the flat cap as origional. Any insight or correction?

 

[Keoke]

Hi Bn2

To accommodate any sort of arc protection for the points inside the cap you will be required to use the stepped end cap for clearance of that component. This is case whether you use the original Capacitor or the the more updated diode unit.

The center hole pointing up is just the position it attains when the two pump halves are correctly oriented and it is installed on the car.---------------------Keoke