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Again and again that SU fuel Pump !

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Brit_Brother

Brit_Brother

Freshman Member
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Hey Keoke if you are around.
Remember I followed your advise and changed my (almost) new SU pump for a brand new electronic one ?

Well today again same problem : the pump stops and starts back whis a gentle hit !
As burlen still as not sent back my first pump under warranty repair since 2 months (long isn't it?) I can't use the car kicking that pump every miles or so.

What is wrong with those new SU pumps ?

I read something in this Forum about the need to re-adjust brand new SU pumps after burn-in ... But i can't find it back.

Any advise before I install a cheap (and reliable) Facet pump will be appreciated.

GRRRRRRrrrr
 
I say there ole chap, never heard of this problem with the electrics. However, the first thing that comes to mind is the throw over point of the pump is maladjusted-Burlens fault. This would require removal of the pump and either screwng the armature in 1/3 of a turn or out 1/3 of a turn. Other than that shock activating an electronic pump might suggest a poor electrical connection someplace inside, or they use plastic bearings now and they might be buggered a bit.---Sorry to hear you have a problem.---Keoke /bcforum/images/%%GRAEMLIN_URL%%/frown.gif

I suggest you give Burlen the /bcforum/images/%%GRAEMLIN_URL%%/devilgrin.gif
 
I will try the 1/3 turn trick.
As I already changed all the fuel line, do you think it is worthwhile to add a filter between pump and fuel tank ?
And If I add this filter should I suppress the one I have got before the carbs ?
 
Brit_Brother said:
I will try the 1/3 turn trick.
As I already changed all the fuel line, do you think it is worthwhile to add a filter between pump and fuel tank ?
And If I add this filter should I suppress the one I have got before the carbs ?
Click to expand...


If you think the tank might be silted up then a filter at that point will help but better clean out the tank. No leave the one in just before the carbs. Do you see any debris in the front filter?? If you add this additional filter you will be required to add an earth connection from the fuel tank sender to the car frame.---Keoke
 
No, no debris at all in the front filter (i have put a glass transparent one so I can monitor easily ), I just wondered if debris might be causing that problem. Like you I don't undestand that an electronic pump reacts to hits.
I don't really want to change the tank, it is not new but in good shape and no leaks.
 
Yes debris could cause the problem take a look inside the tank and make sure it is clean, also look on the iput to the pump, if that is the problem You will see the bits collected on the pump's filter screen.---Keoke
 
I haven't relied on an SU fuel pump for decades.

IMG_6644.jpg
 
One of the concerns that I have is electrical continuity.

Can you verify that you've got a good ground at the pump? I don't know if these pumps use a separate ground wire or ground through the body of the pump. Whichever, I would recommend that you check the electrical connections(bullets, spades, whatever) and make sure that they have got a good solder, or crimp and solder).

HTH
 
RonMacPherson said:
I don't know if these pumps use a separate ground wire or ground through the body of the pump.
HTH
Click to expand...
They do.
6179-pumpground.jpg
 

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Randy! I have not relied on anything but an electronic SU Fuel Pump for centuries.---Keoke-- /bcforum/images/%%GRAEMLIN_URL%%/laugh.gif
 
Brit_brother -

Do you have a filter before your fuel pump? Sounds to me like you have crud in your tank
 
Okay, a concern there is you;re going from the spade on the pump body to a bolt facing painted surface.

A recommendation is to verify the crimp on both ends of the wire(possible solder reinforcement) then undo the bolt and scrape the paint under the bolt,better yet, undo the plate scrape a juncture of paint from both the plate and where it mounts. Need a GOOD ground on electronic equipment.

I've seen many many components that just needed the ground cleaned up and verified.
 
Yeah Greg, you need to pick another spot to connect the ring connector to that is directly on the chassis.--Keoke
 
Hi Ron,
Thanks for the concern, but my pump works fine. I crimp and solder my wires. The paint under the bolt was dremeled away and bulb grease put on both sides of the ring terminal to protect against corrosion. /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
 
Hi Keoke,
That wiring configuration is how I found it on the car. ?
6183-pump.jpg
 

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If there is continuity between the car's chassis and the bolt mounting Greg's pump bracket... there is no need to remove paint from the bracket. And there must be continuity because Greg says it's running.

Randy, how long have you been running that style of Facet pump and what do you think of it? Can you compare its noise level to the inexpensive stamped metal frame version?
 
dklawson said:
If there is continuity between the car's chassis and the bolt mounting Greg's pump bracket... there is no need to remove paint from the bracket. And there must be continuity because Greg says it's running.

Randy, how long have you been running that style of Facet pump and what do you think of it? Can you compare its noise level to the inexpensive stamped metal frame version?
Click to expand...
I'm sure it's been on there fifteen (15) years, or more.

It's clearly audible when turning on the ignition, but I don't notice it once the engine has started.

That Interupter Style Facet pump (available from Pegasus Racing) did require a regulator, as it produces 4.5 PSI. I run the Webers at 2.5 PSI (as you would for the SUs).

IMG_6654.jpg
 
GregW said:
Hi Keoke,
That wiring configuration is how I found it on the car. ?
6183-pump.jpg
Click to expand...

Change it! I am sure Lucas did it an he couldn't even figure out earth the right way around.---Keoke- /bcforum/images/%%GRAEMLIN_URL%%/laugh.gif
 
dklawson said:
If there is continuity between the car's chassis and the bolt mounting Greg's pump bracket... there is no need to remove paint from the bracket. And there must be continuity because Greg says it's running.
Click to expand...

Well now DK that depends on how you define continuity. For example Standards define a good ground interface as having a DC resistance of 1.5 Milli Ohms. Similarly, a functional Lightning ground will have a DC resistance of 1/3 Ohm.
It was never the intent to create the ground circuit interface through the fastener. The fastener is there to perform its sole function of holding the two direct interfaces in a tight fixed position.
For example lets say the complex ground interface has a "DC continuity" measured at 3 Ohms. Being prudent we have established a safety fuse in the circuit of 10 Amp's the pump shorts! the current in the circuit is limited to 4 Amps by the ground circuit resistance alone.
Over time the wiring is going to heat increasing its resistance further limiting the current to the fuse and given enough time the wire harness will melt protecting the Fuse!---Keoke- /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
 
"Over time the wiring is going to heat increasing its resistance further limiting the current to the fuse and given enough time the wire harness will melt protecting the Fuse"
You need better explain that one. However, I will agree with your point above though that if you have 3 ohms of resistance through a bolt you're using as ground... you've got a bad connection. But you see... his pump runs. Quite a number of ground connections on LBC (for better or worse) achieve their earth connections using fasteners, not spots scraped bare of paint on the chassis.

Warning: Sexist Anecdote Below.
Do you know the difference between an engineer and a scientist? Place an attractive woman in the middle of a room and tell each they can only step half the remaining distance to reach her. The scientist will complain "But I'll never get to her", while the engineer says "I'll get close enough". The point? Practical applications and text books don't always coincide.
 
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