wiring for fuel pump

[Mark Jones]

I have recently rebuilt and reinstalled my A4 in a 1977 Catalina 30. I have two challenges. First I cannot get a flow of fuel from the fuel tank to the fuel pump. Any suggestions? Second issue is correct wiring for the fuel pump. I have the wire from the electrical pump coming to the oil pressure unit. I have one blue wire running through the wiring harness to the instrument panel for the oil pressure guage. How does the oil pressure unit get the power to run the pump? From the positive pole of the coil? Should I run a wire from positive pole of coil to pressure sending unit and the fuel pump should run when the key is turned on is that correct? Is there anyother wiring related to the fuel pump I need to be aware of?

[rigspelt]

1. By oil pressure sending unit, do you mean the oil pressure safety switch, or the oil pressure gauge sender? They should be two separate devices.

2. I ran a fused purple wire from the positive terminal of the coil (essentially -- actually I use a bus for the primary ignition circuit to avoid overloading that coil terminal with too many wires) to one side of the oil pressure safety swicth, then another purple wire from the other side of the oil pressure safety switch to the fuel pump. If the fuel pump is attached to the block, make sure that connecton allows a good electrical ground to the block. If the pump is not attached to the engine, it needs a ground wire. If your system is fused, check the fuse.

3. How do you know there is no fuel flow from the tank to the pump?

[Marian Claire]

Does the pump have a good ground? Maybe try a squeeze bulb to prime the system. Any cutoffs that did not get reopened? Dan S/V Marian Claire

[smosher]

The fuel pump should make a clicking noise when in use. Its wired from the + side of the coil to a fuse, from the other side of fuse to one side of a oil pressure switch. The other side of the switch to the pump. I ground mine from the pump to the engine.

A great suggestion I got from Mr Neptune is to use a gas pressure gauge. A quick glance and you know if you have gas at the carb.

Steve

[ArtJ]

Do all pumps click

I don' t think that all mfgrs pumps necessarily click all the time but only
keep a pressure differential between input and output.

Am I right?

Which pumps click often and which don't?


Thanks

[smosher]

I use the facet and it clicks all the time, sometimes louder then other times.

Steve

[roadnsky]

I have recently rebuilt and reinstalled my A4 in a 1977 Catalina 30. I have two challenges. First I cannot get a flow of fuel from the fuel tank to the fuel pump. Any suggestions? Second issue is correct wiring for the fuel pump. I have the wire from the electrical pump coming to the oil pressure unit. I have one blue wire running through the wiring harness to the instrument panel for the oil pressure guage. How does the oil pressure unit get the power to run the pump? From the positive pole of the coil? Should I run a wire from positive pole of coil to pressure sending unit and the fuel pump should run when the key is turned on is that correct? Is there anyother wiring related to the fuel pump I need to be aware of?

Mark-
Do you know WHAT fuel pump you have? What is it's PSI rating?

I notice that your vessel is a CAT 30. In the TECH NOTES, Don points out that you need more PSI in a pump because of the distance from your fuel tank.
"For Catalina 30's, Columbia 36's, and any other boat where the fuel tank is lower than, and more than 6 or 8 feet from, the engine, the model 476-087E is a better choice, with a nominal rating of 4 PSI."

The boyz have given you good instruction for your wiring as well as checking for proper flow, so I won't repeat that advice.
Here is a pic of the OIL PRESSURE SWITCH though just for clarity.
(And for Shawn)

For the record, FACET pumps do "click" all the time.
Louder when they're not full and "looking" for fuel.
Quieter when they are full of fuel.
Trust me on this. I've been listening and watching mine ALL summer...

[sastanley]

Bah...I'll stick to my mechanical pump. I just bought a rebuild kit and added it to my spares box.

Thanks for the pic Jerry...but I know that one is not of YOUR boat.

[Mark Jones]

Wiring for fuel pump

I don't seem to have a "switch" I have the pressure sensor that goes to the instrument panel but it is forward near the flywheel. Also no indication of any fuse. Could this have been wired directly off the coil to the fuel pump?
I can tell there is no fuel getting to the pump by a clear inline filter between the pump and tank. When I disconnect the fuel line at the copper line and stick the hose into a small water bottle full of gas, it sucks the fuel right up. I recently bought the pump from Moyer and saw only one pump in the catalog.
I will get down to the boat again tomorrow afternoon and try the inline bulb pump to see if the fuel will flow from the tank to the pump that way.
Can the oil switch be procured at an auto parts store or is it a "marine" part? If it can be purchased at an auto parts store any advice on what to ask for i.e make or model since Atomic 4 is not carried that I know of? Thanks again, as you may have noticed by the date/time group of my original post this is keeping me up at night

[msmith10]

The pump should be wired:
From the positive of the coil to the oil pressure safety switch, and from there to the pump with an inline fuse.
The oil pressure safety switch is located on the carb side of the block down low beneath the fuel pump location. I believe it is a little forward of the oil pressure adjusting screw. It's purpose is to keep the fuel pump from being energized if the motor is not running (ie, you don't want the pump running when the ignition is on but the motor isn't running, or you risk pumping your bilge full of gas if there's a leak downstream of the pump). If it's not installed, there is a fitting there for one (I think it's a pipe plug). They were not installed on motors with mechanical pumps but are required for electric pumps.
For testing purposes, you can wire straight from the coil positive to the pump.
If the pump is working but not delivering fuel to the carb you may need to prime the water separator (if you have one). You can fill the separator manually or with a rubber bulb like on an outboard.
As mentioned above, you may also need the higher pressure pump (normal pumps give 1-2 psi, the higher pressure give 2-4 psi) if you have a Cat 30 where the fuel tank is mounted low and gravity is not assisting fuel pressure. Both of these pumps are listed in the Moyer catalog.
The oil pressure safety switch (illustrated a couple of posts up) is also for sale on the Moyer site (look under fuel pumps).

[Marian Claire]

MJ: Do I have this right? The pump pumps when hooked to a small container of gas but not when attached to your tank? If so the pickup tube could be plugged or disconnected or not reaching the gas. How full is the tank? Try blowing air back to the tank to make sure the pickup tube is clear and reaching the fuel. You should hear bubbling in the tank. If you can blow but do not hear bubbling the tube could be disconnected. Dan S/V Marian Claire

[roadnsky]

MJ-
Again, do you know WHAT fuel pump you have?
What is it's PSI rating?

Also, Dan's advice is excellent and might just lead you to your issue...