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Discussion Starter · #1 ·
Can anyone help with some pictures and tips about mounting a Facet Silver Top electric fuel pump in my 71 Spider (converted to Webers)?



My Spider has been bogging at about 5500 rpm on steady acceleration. I have fresh filters, a coated tank, a Malpassi Filter King adjusted to 3 PSI, fresh points, and fresh plugs. Webers were tuned a few months ago by a pro but the bogging remains.

I also have a small squarish electric pump that I suspect is probably 15 or more years old... probably part of the PO-purchased Weber conversion kit. Having ticked off the other possibilities above, I suspect this small pump runs out of steam (OK fuel pressure) under the load of acceleration. Besides my mistress demanded something for Christmas :D, so I purchased her the pump along with a mounting kit and the 90 degree fuel line hookups. Haven't bought anything for the wife yet though :eek:

The instructions which come with the new pump 'recommend' mounting it vertically with the input from the tank at the bottom and the output at the top. I'd planned to mount it horizontally, in the right rear of the car where the current pump resides, with the fuel input closest to the tank. It had never occurred to me to consider mounting the pump vertically (which I suspect would be a small PITA) until I looked at the instructions. I'd prefer to mount it horizontally of course .

Additionally, I haven't pulled the old pump yet (it's 35 degrees today!) and so I don't know how the bracket on the Silver Top lines up with any brackets or mounting points on the car. I'd appreciate any advice and experiences you guys could give.

Finally, I bought the Silver Top as it was recommended here as the best low pressure pump for Weber Converted cars. I've read that the fuel pressure is 2 - 5 psi. Is this adjustable? If so, how? Do I even need to worry about that since I have the Malpassi pressure regulator?

Thanks!

Lokki
 

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If you have carbs, they don't actively need fuel when the engine is greater than 5,500 RPM....that's what the bowl on a carb is for. It fills when required, and is the fuel reservoir. Then once it goes down in level, the needle valve opens up and refills the bowl.

I would say there is something wrong with the set up. If it was working with your old system, then it is most certainly something with the new carb setup.
 

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Discussion Starter · #3 · (Edited)
Thanks Paul....

... I would say there is something wrong with the set up. If it was working with your old system, then it is most certainly something with the new carb setup.

Paul - thanks for you help. The carb set up isn't new per se - as I noted it was put on the car by the PO (I'm guessing) more than 15 years ago. It's had a variation of this problem since I started restoring the car two years ago. It's running better and better as I work on the car - she started on the first crank this morning at 39 degrees. She pulls cleanly and strongly except for the stumble and bog I mentioned above

What would you say "something wrong with the set up" means? Could you pin that down a little more perhaps?

You can see the list of things I've chased so far.

In any case I have the pump and it shouldn't hurt anything to put it so, so my original questions remain.
 

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But Mad North-Northwest
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Uh, I don't think that necessarily follows, Paul. If the pump is failing and can't keep up with the flow @ pressure requirements the bowls are not going to stay full.

Regardless, Lokki, you're better off installing the new Facet anyway. They're good fuel pumps and those little cube ones are junk. If you're lucky like me the hole spacing on the mount is the same and you can fit it where the old fuel pump is (mine on the Giulia is in front of the fuel tank, passenger side, but no pics).

Fuel pressure is not adjustable at the pump. Different Facet models have different flow/pressure characteristics. Sounds like you have the same one I got which is 4-5PSI output pressure: tad high for Webers so use the inline regulator to dial it down to 3-3.5PSI.

The Facet has a 70um inlet filter (cleanable) so it doesn't need a filter from the tank. You should probably install a finer inline filter before the carbs just to be safe, though.
 

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I would say it's something to do with the jetting of the carbs.....but it's been a long time since I've worked on carbs.....

As far as the fuel pump goes, I'll wait for others to chime in.
 

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Discussion Starter · #6 ·
Thanks Gubi - that's helpful. I'll take pics as I go.... the weather is supposed to warm up a little next week... sooo
 

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Discussion Starter · #7 · (Edited)
Here are some pics that hopefully will be of use to someone approaching the same project.

First a picture of the old and new pumps. The old pump (foreground) is also a Facet - a POSI-FLOW EFP-3 which as best I can determine has has 1.5 to 4.0 PSI with a max flow rate of 23 GPH. The new pump is the Facet Silver Top with 2.0 to 5.0 PSI with a max flow of 36 GPH at 2.0 PSI and an average flow of 23 GPH. (Note these figures vary depending on the web site).



Next some pictures of the mount from a couple of angles. I believe that this mount is the original mount for the SPICA pump.... The D*mn PO had mounted the EFP-3 to it by drilling a hole for a single bolt. However, it had never come loose, so good enough was good enough I guess.

The mount which is itself mounted to the chassis behind the right rear wheel is actually a double-layered piece. The bottom layer is held to the chassis by three bolts: two horizontal to the ground with the bolt heads facing the rear of the tire, and the third mounted vertically; bolt head towards the ground.


Machine


The second layer is isolated from the bottom layer by three rubber mounts. Each rubber mount is a 'doughnut' which has a steel sleeve in the center with a bolt running through it. These bolts hold the two layers together.


Auto part Vehicle Metal


The pump itself is mounted to the second, isolated layer by two bolts. Unlike Gubi's car, the bracket welded to the pump did not match up with anything on the original mount. I had to drill two holes in the second-layer piece and buy a couple very short bolts (to clear the lower layer of the mount) and a pair of nylock nuts.

Note that you have to ground the pump body to the car chassis -you can't ground the pump to any part of the pump mount because both layers are isolated from the chassis by rubber mounts or grommets. So, you'll need a long ground wire. In the picture above I've taken some heat-shrink tubing I had and run the ground (yellow head) side-by-side with the black-wired positive lead, just for neatness.

As a final note - the official Facet Mounting kit (about $10) is an unnecessary (and in fact useless) purchase for this application. It consists of two rubber isolators (the Alfa mount already has three) and a grounding wire that is too short to use in this application.

Wire Resistor Technology Electronic component Auto part


I'll be mounting and testing the pump next; I'll report back as to whether or not it resolves the stumble @ 5300 -5500 on hard acceleration. Hope so!
 

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Discussion Starter · #8 ·
Reviving an old thread to give a conclusion that changing out the pump -did not- resolve the stumble. Nothing fixed it, including putting in a new 123 Distributor, until I went to a full Euro manifold system, replacing the SPICA manifold to Weber conversion set-up. My theory is that the rubber seals between the carbs and the SPICA manifold were old and started leaking air, changing the mixture, when the engine was at the 5300 -5500 rpm range.

Anyhow, conversion to the proper Alfa Weber set-up fixed the problem.
 

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Reviving an old thread to give a conclusion that changing out the pump -did not- resolve the stumble. Nothing fixed it, including putting in a new 123 Distributor, until I went to a full Euro manifold system, replacing the SPICA manifold to Weber conversion set-up. My theory is that the rubber seals between the carbs and the SPICA manifold were old and started leaking air, changing the mixture, when the engine was at the 5300 -5500 rpm range.

Anyhow, conversion to the proper Alfa Weber set-up fixed the problem.
Thank you for wrapping this up. I saw that the thread was old, but it had a lot of good fuel-pump-carburetor-theory information. Its always nice to have an ending! That facet mount looked gigantic, I'm a bit surprised that it fit under there!
 

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Two conclusions that I draw from Loki's experiences:

- Although the instructions that come with the silver top Facet tell you to mount it vertically, it looks like Loki mounted his horizontally and it worked OK (did I understand that correctly?). There is a filter and clean-out at one end of the pump, which is the biggest reason I can see for vertical mounting: that puts the clean-out at the bottom so gravity traps any debris there.

- My experience with Spica conversion agrees with Loki - those O-ring carb mounts just don't seal very well. Going to a factory carburetor manifold eliminates those seals and also provides more elegant throttle linkage.

Loki: Thanks for the post mortem. I wish more people would conclude threads that way.
 

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Discussion Starter · #11 · (Edited)
MNVXer, yes, that mount is pretty big, but it's the existing original from the factory. Except for drilling a couple holes to actually mount the pump (since the original holes didn't quite line up), nothing was changed. I may have a picture of it in its final installation location somewhere in my files; if I come across it , I will post it here.

Jay - you're correct that I mounted the pump horizontally....that was the best way to mount it using the existing pump mount, giving the cleanest look and most safe and solid mount point.

I went with the horizontal mount after reading the info on the pump -
(Gold Flo | Motor Components, LLC | Facet Purolator)

It says that mounting the pump vertically isn't mandatory in every case.

" For best results, mount the pump close to the fuel tank and below the fuel level. The pump is self-priming to 24 inches vertical fuel lift. Vertical mounting is preferred to assure maintenance of rated pressures."

With my old-style gas tank which has the fuel line outlet at the bottom of the tank priming the pump is not an issue. It is pretty much a level shot from the tank outlet to pump input. No worries about 'vertical lift' for priming. Frankly, I would think that even using a later style tank which pulls out the top of the tank should be OK as the drop from top of the tank to pump intake would (eyeballing things) be less than the 24 inch max self-prime height.

As for loss of pressure from horizontal mounting,since the min rated pumping pressure is actually close to the max pressure I need (2.5 lbs) and I have to run a pressure regulator anyhow, any potential loss of pump pressure from mounting horizontally is irrelevant.

So far, the internal filter on the pump hasn't shown any hints of clogging, but then my tank had just recently been flushed and coated before the pump was installed. I've had it close to a year now and, so far, so good.
 

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I just mounted a Facet red top, somewhat vertically and at the back of the car, left side, just infront of the fuel tank. see photo although note that the exhaust is removed. My car has never had an electric pump so I didnt have the braket shown above and so I used the Facet rubber mounts.

The advantages of this spot are the proximity to the tank, the "almost" vertical mounting and the simple plumbing into the existing rubber fuel hose which runs between the tank and the metal fuel line.

However Im worried about the proximity to the exhaust. What do people think? any idea how hot it gets near the rear silencer? is the fire risk too high if a fuel hose were to fail? The original arrangement also had a rubber hose in this location, but then I guess with the mech. pump, there would be less fuel going everywhere in the event of a failed hose.

I think my wiring and plumbing is solid, but now this thought is in my head, Im not sure how comfortable I am.... anyone else used this location?
 

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" For best results, mount the pump close to the fuel tank and below the fuel level. The pump is self-priming to 24 inches vertical fuel lift. Vertical mounting is preferred to assure maintenance of rated pressures."

With my old-style gas tank which has the fuel line outlet at the bottom of the tank priming the pump is not an issue. It is pretty much a level shot from the tank outlet to pump input. No worries about 'vertical lift' for priming. Frankly, I would think that even using a later style tank which pulls out the top of the tank should be OK as the drop from top of the tank to pump intake would (eyeballing things) be less than the 24 inch max self-prime height.
sorry for the commenting on the old thread, but does this mean that I really don’t need the in tank pump if this is installed on the right side where the original spica electric pump was?
 

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Discussion Starter · #14 ·
Gkmyer - I don’t visit the BB very often these days but happened to do so today and saw your post on this old thread. Reading back through my old post, I see that I -speculated- that the facet pump might be able to pull fuel from the fuel tank without the need for an in-tank pump. However, I never personally tested that theory.

My car is a 1971 - in 1971 the fuel tank has its outlet to the fuel pump on the bottom side of the tank, close to the exhaust pipe. This means that gravity feeds fuel over to the electric pump which is located on the right side of the car, just in front of the right rear wheel.
 

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But Mad North-Northwest
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I've got a Facet Gold-Flo from Centerline mounted in that manner: it's in the old SPICA pump position with a top-draw tank. With twin carbs it's been working fine for me without an in-tank pump.

The Gold-Flo is self priming, and this model also has an internal anti-siphon valve. This closes when the pump shuts off and prevents the fuel draining back into the tank, which means the pump doesn't need to prime from dry every time you start the car.
 

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I've got a Facet Gold-Flo from Centerline mounted in that manner: it's in the old SPICA pump position with a top-draw tank. With twin carbs it's been working fine for me without an in-tank pump.
Did you just use a standard piece of fuel line from the fuel level sending unit to the bottom of the tank? Did you put any kind of filter on the end?
 

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But Mad North-Northwest
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So the sending unit I have is aftermarket, and has a metal tube to the bottom of the tank. There is a zip-tied plastic screen on the intake. If you're looking for something to replace the in-tank pump I do not believe standard rubber fuel hose will work as it is not designed to be submerged in gasoline. You could likely braze on a metal tube to extend your sender to the bottom of the tank, or of course just buy a new sender.

You don't really need a filter before the pump, the Facet has a built-in 70um cleanable screen. I have a Filter King right before the carbs to serve as a fine filter and pressure regulator.
 

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Is the facet mounted horizontally upside down? I am concerned that the brass fittings give less clearance so I have to add a spacer to get the shield to fit over, which moves the shield closer to the ground.
 

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But Mad North-Northwest
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No, it should be mounted vertically, with the removable filter at the bottom.

Here is my install in the 1974 GTV. I got some rubber isolators (M6x1, I think?) that screwed into the existing fuel pump holes. I then made a short steel bridge to match the mounting distance of the facet pump. The Facet is grounded to body via a short wire installed across the rubber insulator.

1641276
 

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Gubi, I am planning to install a gold flow for the purpose of filling the bowls and then running with my existing mechanical pump. (68 spider). The gold flow comes with only one fitting - the ones you installed look different from the one supplied with the pump. Do you know the thread size?
 
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