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Fuel pump circuit cutting out on start up

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Vette's update made me go back and reread this topic. I had missed Michael's comment that he had tried it with the alternator wires disconnected and it still failed. This step
eliminates electrical noise so forget trying the filter cap. Since you had also wired around the ignition switch, this eliminated that possibility. What this appears to leave is the white wire. If the white wire has the insulation burnt off somewhere and you left either end hooked up to either the fuel pump or the lower right lug of the fuse block when you did your 12 gauge wire bypass test, then the white wire was NOT eliminated as the possible cause of your problem. It will short the fuel pump voltage to ground from either end and cause the pump to stop working. Perhaps you did have the wire disconnected at both ends when you did the test from terminal 1 of the fuse block, or perhaps it just didn't fail during that test. .... Let us know what fixes it.
 
[ QUOTE ]
I had missed Michael's comment that he had tried it with the alternator wires disconnected and it still failed. This step eliminates electrical noise so forget trying the filter cap. Since you had also wired around the ignition switch, this eliminated that possibility. What this appears to leave is the white wire. If the white wire has the insulation burnt off somewhere and you left either end hooked up to either the fuel pump or the lower right lug of the fuse block when you did your 12 gauge wire bypass test, then the white wire was NOT eliminated as the possible cause of your problem. It will short the fuel pump voltage to ground from either end and cause the pump to stop working.

[/ QUOTE ]

Ed--

At Dave Porter's suggestion I reran the "no alternator" test yesterday because the first time I did not disconnect the sensing wires, just the heavy output lead. This time the pump worked fine when connected to either the white wire or jumped to the switched pin BOTH before and after startup. When I reattached the alternator wires the pump dropped out as soon as the car fired over. Whether I got it wrong the first time or not I just don't know but the alternator definitely seems to be involved.

I called Balcamp (the NAPA manufacturer)today and one of their tech's said that yes, they have had problems with the pumps from alternator spikes, transients, etc. and suggested that I put in "a filter". Well, the pump's replacement is already on hand and is scheduled for installation tomorrow but not before I go over the white lead circuit from stem to stern one more time.

BTW I did NOT disconnect the white lead at the fuse block (as you suggested) and though I don't understand how it could be shorting out the jumper (especially since the white lead is now successfully supplying the current to energize the power relay circuit from the battery to the pump) I will disconnect it and check that off as a possible cause.
 
HI MIchael, As I said in an earlier post I think the alternator output is dirty or "That" particular pump is overly susceptible to noise. This does not imply that all of that vendors pumps are equally susceptible but Balcamp's response seems to suggest that might be the case.Will follow the next episode.---Keoke
 
Very good information. So is the condenser the only filter element you need or did NAPA suggest something else? Or is the fix to sort out the source of the voltage spikes?
 
I promised that prior to replacing the pump with the Masters (Autozone) E2019 unit I would do all of the testing that I could to determine conclusively whether or not this was all simply a problem with the wiring.

1. First thing I did was to remove the power relay and hook the pump back up to the white power lead. I turned on the ignition, the pump operated and then--NOT IMMEDIATELY as before, but about 20-30 seconds after the engine fired over--dropped out.

2. Then I disconnected the pump from the white power lead and ran a jumper to the battery. The pump started pumping right away and continued pumping after I started the engine.

3. Then I disconnected the power lead and ran the jumper between the switched post at the fuse block and the pump. The pump ran when I turned the key on and (as before) shut off when the engine fired over.

4. Then I switched the jumper over to the unswitched post at the fuse block and the pump started to run and continued to run after I started the engine for a minute or so. THEN THE PUMP DIED and I noticed that it was hot to the touch.

5. I reattached the jumper to the battery and now the pump would not run at all. Nothing--Dead(hot)pump.

6. I removed the NAPA pump and mounted, plumbed and wired (to the white power lead) the Masters unit, turned on the ignition and the pump began to operate. I fired the engine over and the pump continued to operate--I ran the car for about 10 minutes and the pump operated fine.

7. I tested the (now cool) NAPA pump on the bench with a 12 volt converter--It ran fine, though it was running with an open head (no fuel).

As best I can tell the NAPA/Belkamp Posi-Flo pump has some issues, to say the least. Don't forget that I went through two of them--the first one lived a shorter but similarly unhappy life. If someone is interested in performing further tests on the pump to see if it works with a line filter, etc. etc. I will be happy to send it along. Otherwise it is going to be mounted on the wall in my Hall of Shame Gallery along with the cracked oil pickup tube from my 100.

A note to Ed Kantner--it was my sincere intention to disconnect both ends of the power lead in the next step of testing as you suggested, but unfortunately the NAPA pump decided to give up before I could get that far. But given that the white power lead operated the power relay circuit and is now powering the new pump I think it can be pronounced okay.

A note to Dave Porter--I checked the rear of the control box (regulator) and all the connections were cut away as they were supposed to be.

I'll post picture of the new installation and the NAPA pump later today.
 
Hi DK, The best fix as has been demostrated here is to locate the sensitive Item or the source of the problem. On the other hand, I do not recommend the use of the capacitor fix. However it can be used as a trouble shooting aid to locate noise sources.Installation of the capacitor introduces a single point failure in the sytem so we do not want to initiate that possibility.There are aftermarket inductive filters that can be installed in the line that circumvent this problem. ,Most high quality radio systems include one on their power input leads. I hope this clarifies the issue.---Fwiw---Keoke
 
/ubbthreads/images/graemlins/thumbsup.gif Good Show Michael.---Keoke
 
Here's a picture of the Masters E2019 fuel pump installed. As you can see it is a good fit. It is also very quiet--I mounted it on a rubber pad and put rubber between the bracket and the body of the pump.

I'm sure happy to put paid to this project.
 

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And here's a picture of the NAPA pump about to experience a fitting disposition.

Go Canes!
 

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Good job Michael! You are probably not in the mood to mess with it anymore but you may want to consider adding an inline fuse to protect against the white wire from ever getting too hot espescially since you have the white wire cable tied against the fuel line.
 
[ QUOTE ]
you may want to consider adding an inline fuse to protect against the white wire from ever getting too hot espescially since you have the white wire cable tied against the fuel line.

[/ QUOTE ]

WHAT--And ruin the car's originality?
 
Re: Fuel pump circuit cutting out on start up *DELETED*

Post deleted by Keoke
 
I have one last question so maybe this isn't the end.

The NAPA pump looks like it says "Facet" but that doesn't look like any Facet pump I've seen. Is that a 2-3 psi, positive displacement pump (that goes tick, tick, tick)... OR, is that a gear-rotor pump that goes "whir"? Likewise, what type of pump is the AutoZone, Masters pump?
 
Re: Fuel pump circuit cutting out on start up *DEL

That's right Keoke. I said " fuse " not filter. /ubbthreads/images/graemlins/lol.gif
 
Re: Fuel pump circuit cutting out on start up *DEL

Yep ED, I had them filters on my mind and getting electrical conductors off fuel lines isn't such a bad idea in my mind either---Keoke /ubbthreads/images/graemlins/laugh.gif
 
Michael!, "Facet Filter for Solid State Pumps" P/N 479735 @ $5,10 ea "---Keoke- /ubbthreads/images/graemlins/tongue.gif----Mus be an inline fuel filter can not get good data on it yet.
 
/ubbthreads/images/graemlins/yesnod.gif DK it is a Facet POS I FLOW pump.---Keoke
 
[ QUOTE ]
The NAPA pump looks like it says "Facet" but that doesn't look like any Facet pump I've seen. Is that a 2-3 psi, positive displacement pump (that goes tick, tick, tick)... OR, is that a gear-rotor pump that goes "whir"? Likewise, what type of pump is the AutoZone, Masters pump?

[/ QUOTE ]

This is the NEW Facet pump--made by Balkamp which seems to be a division of or owned by NAPA. It may or may not be any different than the older metal cube-shaped ones, though I think they were made for NAPA by someone else.

In any case it goes tick-tick (quite loudly) and is, I believe, a diaphragm pump like an SU. The Masters pump also ticks though much more gently.

I appreciate the input about not tie-wrapping the electrical lines to the fuel lines and will also install a line fuse, though I prefer to do it closer to the power source to better protect the wire. I also need to remove the black plate shown in one of the photos, which was the mount for the now-dead double-headed SU.
 
Hi Michael,
Glad things are working. I believe on your original wiring that a switched white wire to the ignition coil joins another white wire at the ignition coil & proceeds to the fuse block terminal A3. (The input side of the 35 amp fuse). Another white wire on A3 runs back to the fuel pump. It's quite easy to put a 10 amp inline fuse between this white wire & the fuse block terminal A3. I did a similar thing just because this wire is somewhat vulnerable to mechanical damage.

All in all, I still don't know for sure what caused your problem. The old style Facet -(small square) does not seem to have any similar problems. Still wonder if a marginal ignition switch or connection is causing some problems.


It seems like the old SU might be pretty good & worth fixing & keeping. At the worst, SU repair kits are available to replace the internals.

Your original problem with the SU pump sounds like the adjustable pull rod is not permitting the contacts to properly toggle. This could be caused by the diaphram stiffning just enough to prevent proper travel/toggling of the contact. "It pumped once when power was applied & again when power was removed."

If so, the pull rod is adjustable by rotating the diaphram on the threaded pull rod to achieve proper adjustment for reliable toggling. I have heard stories of brand new SU pumps needing this adjustment to permit reliable toggling of the contacts. Maybe yours was marginal from the start.

I believe adjustment involves setting the rod length to where the contacts just toggle when the diaphram is pushed by hand & then unscrewing (lengthening) the pull rod on the diaphram an additional 2/3 of a turn. The SU shop manual gives a good procedure for setting the toggle throw & contact adjustments.

I would be happy to fix it for you, or at least try, if you want to go to the trouble of sending it.
D
 
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