Adding a electric fuel pump, suggestions?

shanon

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Hello Gruppe,

After investigation to my E3's poor running issue, I determined that it is suffering from a fuel delivery issue. With a fuel pressure gauge installed, it is not showing above 2psi with the stock mechanical pump. Seems low,should be about 3.5psi.

I have had great experience with a Facet electric fuel pump in my E9 hot rod, and looking to the gruppe as to which unit you prefer and where is the pump being placed. Unlike my tweaked E9, I don't want it visible in the trunk. The E3 is a different rig.

Also, how are you powering the unit (separate switch/circut or tapped into the factory loom)?

TIA!
 
 
Well, if you have a non-functioning defrost or rear glass without defrost like I do, then run power off the defrost line, this way you already have a switch in a convenient location.
 
I use a VDO in-tank pump from an E28 as my electric fuel pump. It's in the tank, keeps cool and never loses its prime.
 
If you decide to install an electric fuel pump, the most important component of that modification is an automatic fuel pump cutoff switch. Whether is controlled by an inertial switch, an ignition signal or an oil pressure sensor, it is a must have in carburetor cars.
 
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If you have carbs, 2 PSI should be plenty. What are the symptoms of your "poor running" issue.

Yea, that was my reaction too. Nothing wrong with installing an electric pump, but I'm skeptical that will solve the poor running problem. Mechanical fuel pumps are pretty reliable, and generally either work or don't. If yours is generating 2 psi then the carbs should be happy, unless the volume is constrained by a kinked line or some similar blockage. As long as the e-pump uses the same plumbing, it may be constrained the same way.

I'd solve the poor running problem first and then convert to an e-pump if that's what you'd prefer to have.

As Dick asked, what are the symptoms of your "poor running" issue? Does it idle OK, but misses at speed?
 
I am running a pierburg pump just like this one - http://www.piercemanifolds.com/product_p/99009.131.htm - along with a Bosch (VW I think) inline filter installed in the trunk. This is the same pump Chris has pictured in his NK.

My pump is attached to the subframe using the rubber isolation mounts, near where Stevehose has his (https://e9coupe.com/forum/threads/final-word-on-electric-fuel-pump-for-carbs.22574/post-165257).

I've also installed the revolution electronics relay, which pumps three seconds of fuel to fill the bowls when first powered up, and will kill the pump if it does not get a signal from the coil that the car is running. https://www.revolutionelectronics.com/Products/Fuel_Pump.html
 
Thanks for the all input gang, very appreciated!

I did something similar to what HBChris did in that I mounted an exterior in-line pump with a switch. Boy, did I forget about the challenges of running wiring in a car with full interior, sheesh! ;)

The Bav is operating/driving nw, but in need of tuning. Carb's and linkage have gotten out whack during my son's and my attempt to diagnose/solve a poor running condition remotely in different locations. Kudos for trying son ;)

I definitely need to 're-learn' the Weber Downdraft 32/36s base line tuning set-up after spending the last year or so playing with DCOEs.

Scenario: Car ran great before I let my son borrow/enjoy it for the summer.....car has been sitting/idle until this week. :-/

Now: car is fluttery/pops/burps/studders when getting on the throttle, but smooths at higher RPM (2500+). I didn't do that before so I am believe jetting is correct.

So, going to review the downdraft's idle, air mix screw, base set up/tuning via YouTube today while keeping 'busy' at work ;)

Happy Holidays!
 
Thanks for the all input gang, very appreciated!

I did something similar to what HBChris did in that I mounted an exterior in-line pump with a switch. Boy, did I forget about the challenges of running wiring in a car with full interior, sheesh! ;)

The Bav is operating/driving nw, but in need of tuning. Carb's and linkage have gotten out whack during my son's and my attempt to diagnose/solve a poor running condition remotely in different locations. Kudos for trying son ;)

I definitely need to 're-learn' the Weber Downdraft 32/36s base line tuning set-up after spending the last year or so playing with DCOEs.

Scenario: Car ran great before I let my son borrow/enjoy it for the summer.....car has been sitting/idle until this week. :-/

Now: car is fluttery/pops/burps/studders when getting on the throttle, but smooths at higher RPM (2500+). I didn't do that before so I am believe jetting is correct.

So, going to review the downdraft's idle, air mix screw, base set up/tuning via YouTube today while keeping 'busy' at work ;)

Happy Holidays!
Check that you are getting accelerator pump spray down each throat when reving the throttle off idle. Check timing. Check the idle jets for blockage. Check that carbs are synchronized.
 
Check linkage to ensure that its not applying tension to the throttle when not pressing the accelerator.
 
The fuel line runs so close to the rocker edge, I have seen the line get pinched by improper jack placement.

Anyone use seafoam??????
 
I found this video very helpful getting a base setting, so I thought I'd share.


Car is running better, but it i need of fine some tuning.

BTW: Tuning carbs while your carb tool kit/stuff is in the trunk of your other car 2hrs away getting its new motor installed is... tedious.....

Stay tuned. (pun intended)
 
The fuel line runs so close to the rocker edge, I have seen the line get pinched by improper jack placement.

Anyone use seafoam??????
That happened to my line at a Goodyear store in the 80’s when I ran Eagle GT tires (a good tire but a pretty soft compound which didn’t last long) They actually pinched/crimped a small hole in it and had to replace the line.
 
car is fluttery/pops/burps/studders when getting on the throttle, but smooths at higher RPM (2500+).
Stevehose said:
Check that you are getting accelerator pump spray down each throat when reving the throttle off idle

Yup. After a car has been sitting, the fuel dries up leaving a gummy residue in the small passageways (like the accelerating pump jets). The engine will start and run OK at constant speeds, but will pop/burp/studder when you get on the throttle.
 
Selection of he proper pump should - if possible - include investigation how it was redesigned towards ethanol content.

Let me copy a text I put into other thread today (about clogging injectors for the car standing still for some time)

There is a huge problem with classic cars (not only) and new gas (E5, E10 ... maybe E15 in the future). The problems is the ethanol additive (5/10/15% accordingly as in the marking on the petrol station).

The ethanol is forced to be added in more and more percentage to make the fuel "more green". And the result is it becoming more green as there is a bacteria living in a tank after even a month of car standing. This bacteria is not helping to have a clear tank or fuel system in general as it is responsible for rust fleaking in the tank.

Additionally ethanol is hygroscopic which means it takes the water from the air.

After some time in the car standing still (starting few weeks) there is a "delamination" of the fuel. It is not a mixture after some time.

This is really huge problem as ethanol is not good for rubber either (hoses, seals, diaphragms).

Some of collectors are draining fuel from classic cars, some using additives (some are even to fight with bacteria) but none of this solution is the remedy.

None of the fuel components in the classic car is durable enough against ethanol additive and all the consquences (water, bacteria...) so even brand new components done with the same technology will soon be a scrap.

The only way to keep it working is to drive the car regularly to have fresh, mixed fuel and to tank the car on the gas stations where the fuel is refilled in the big tanks regularly.

-----------

I'm the victim of this eco approach. My E30 project currently has 5th fuel pump!
In the past I exchange the old fuel, purge the tank, put the kerosene and diesel fuel mixture to flush it and fill it with new fuel (E10 ... the only widely available).
After few months my fuel pump is giving only 2Bar (should go above 3bar). The car can't keep idling and I need to but another pump! :mad:

The real problem is exchanging all to new and keeping the car standing will not secure us and fuel system problems will be more and more visible and expensive and BOSCH or Pierburg parts are sick expensive. The good in a bad there are still available.

Coating the fuel tanks (planes, petrochemical...):
e.g. https://www.3m.com/3M/en_US/p/d/b40067203/
and exchanging fuel lines to plastic or inox or special material is not solving the problem as the pressure regulator, valves or injectors are designed in 70's or 80's.

Might be the only good solution is to check how engineers in Brazil, using ethanol (E20 - 20%) in a fuel started by legislaton in 1977.
They've redesigned their's cars fuels systems completely and became an experts - flex-fuel cars.

 
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