fuel pump for '69 2-liter weber carbs

[hhgt3]

fuel pump for '69 2-liter with weber carbs.

just bought this track car and one of the fuel pumps is making a loud buzzing sound.

pumps are located in the stash box, mounted in a way the fuel cell has to be removed to access. working on it today.

any suggestions with what would be a good replacement pump?

should i do both of them?

and where can i buy them?

thanks for any help.

bob h.

[Grady Clay]

hhgt3, bob h;
Welcome to the Forum
You will find a lot of help here.

With a fuel cell, I assume this is a track car.
Just purchased?

What are your intentions? What is your budget?
Many track cars have had series of mods over the years and sequence of owners.
Some ‘less-than-ideal’ mods must be corrected and brought to current standards.
The fuel system is one.
This is the opportunity to have a completely correct fuel system.

Please post some overall and detail images of your fuel system – every part.

How old is the fuel cell (it should have a manufacture date)?
Has the container ever been damaged?
Has it ever been back to the manufacturer for inspection of the bladder and replacement of the foam?
Is the existing cell and mounting suitable for your use?

This is a good starting point.


Dual fuel pumps (in parallel) may be useful for redundancy (if plumbed with isolating check-valves) but for amateur racing, generally unnecessary.
Most important is maintaining the system (and entire car) in ‘race-ready’ condition.

Important is attention to a properly designed and functioning fuel system.
You should have a circulating fuel system where cool fuel flows past the carburetor inlets and the excess returns to the fuel cell.

There are a LOT of design and installation details to get this right (including properly re-installing the fuel cell).
This thread may be a good place to combine all the available information.

Best,
Grady

[ErVikingo]

When i got mine i had the shop re do the whole fuel system as Grady suggests. No problems since !

Where are you located?

[hhgt3]

Grady,

Thank you for helping with a starting point.

This car is a '69 2-liter track car with street tags which I've just purchased. Car has PCA logbooks dating back to 1999, run on the east coast, midwest and some in Canada, raced by Gary Hess, and I understand car is originally from either Colorado or Nevada, and has been a race car for much of it's life. (not sure about this).

My intent is to run in vintage events and PCA, I live on the coast in Wilmington, NC. Budget is not unlimited, but I want to do it right.

Fuel cell, which I had to remove to get to the mounting points of the pumps, is an ATL 15 gallon tank, which has an "out-of-date" stamp of 12/31/12. Container has never been damaged, and I doubt it has ever been back to ATL for inspection. The foam age is unknown. (I should replace?)

I think the cell and the mounting of it works. For right now I would like to leave the pumps where they are, maybe figure out a way to remove them if needed without having to take the tank out. But I would like to have a plan for how to ideally reconfigure.

With one pump not working, what type should I replace with? In the link you provided to "circulating fuel systems" there was a lot of great information, alot of it over my head, but you mention you prefer a rotary pump.

I would like to learn how to do as much as possible, this forum is incredible, falling back on an HSR oriented shop for the big stuff.

Below are pics.

And I need to add a fire suppression system.

Thanks for all the help.


bob h.


ATL 15 GALLON FUEL CELL, HAD TO REMOVE TO UNATTACH TWO FUEL PUMPS WHICH ARE MOUNTED IN THE SMUGGLERS BOX.



FUEL PUMP, THERE ARE TWO, NO NAME ON THEM.



FUEL PUMPS ARE MOUNTED IN HERE, I'VE TAKEN ONE OUT.



AND FUEL LINES FROM THE PUMPS HAVE A "T" FITTING INTO A SINGLE LINE
AND RUN BACK TO THE ENGINE.



STEEL LINE COMES UP AND "T'S" OFF TO THE LEFT CARB.



AND DEAD ENDS AT THE RIGHT CARB.

[304065]

Hmm so that's what happened to Gary Hess' 69T. I have some photos of my 71 side by side with him on the main straight at Watkins Glen. Even with T power he was competitive because the car had a great suspension and he never lifted.

Ditch all that plumbing and replace it with new Cohline braided line, 7.5x12mm. Carter gerotor pump will produce the correct pressure and cheap at $55. Get yourself a surge tank or better yet, have one installed in the replacement bladder for the fuel cell.

I went the route of braided stainless when I re-did my fuel system for a fuel cell in my 71E. Totally useless and I would never do it again, particularly when you only need 3.5 psi for PMO carbs.

Good luck!

[Grady Clay]

This looks to me as if your 911 has a circulating fuel system (two hose green circle).



On the other end (carbs), it seems to be ‘dead-end’.
You are a prime candidate to re-do the fuel system right.

A number of years ago I posted a well-thought description of a fuel system on Early_S_Regestry.
Unfortunately, one of their reconfigurations lost that thread and post.
I’ll try and reconstruct my design here.

The critical issue with a fuel system for your 911 is safety.
Too often not all the issues are taken into consideration.
Perish the thought that we should ever crash out 911s while racing.
It can happen and we need to be prepared with our design.
I’ll try and help with my lame experience.

Not today. I’m glowing in the dark after some nuclear medical procedure. Keep after me.

The basics are to have everything easily serviceable as you go racing and have the fuel system tolerant of crash damage.
Your life may depend on your (our) good engineering.
Same with your fire suppression system.

Best,
Grady

[KTL]

I agree the braided is somewhat overkill for low pressure systems. However the abrasion resistance provided by the stainless braid is a big safety feature. ESPECIALLY when you're routing it in tight confines like the smugglers box and center tunnel. Also, some organizations require braid inside the car. The center tunnel is unfortunately arguably inside the car, considering there are openings in the tunnel to the cabin.

I like the push-lock Aeroquip "socketless" or Earl's push on hose and fittings where braid isn't a must. It's very tough and not extremely expensive. Easy to work with too. All you need are some cable cutters (cuts hose very cleanly) or a very sharp utility knife, some heat and assembly oil.

That system confuses me. I can't see how it's a circulating system from the pictures. If it dead ends at each carb, where is the return back to the fuel cell? Is it a double dead head- one pump for each carb trio? That would be odd because if one pump fails you've got one bank of cylinders down on fuel.

Grady's advice is hardly lame. This fellow has more Porsche & racing knowledge than an army of us could ever hope to possess!

[rw7810]

Grady - With all respect. I've been running a "dead head" system on my 70 T with Zeniths for 20 years. I tried the recirculating system, but it wouldn't register any pressure. Maybe I was missing something like a restricter in the return line ??

PS: are there any rotary pumps out there any more?? I've been using a Facet Low Pressure Cylindrical Fuel Pump from Pegasus Racing mounted on the front cross bar. Just found this Carter rotary pump and may give it a try.

Carter and Webers

[hhgt3]

grady, the green circled braided lines are for an oil cooler located in the front right fender and run through the passenger side of the interior. the lines dead end at each carb. when you have time i look forward to your thoughts on doing this correctly. and it sounds like i need to join early s registry. thanks

kevin, thanks for your thoughts, i will get up to speed on the fittings from aeroquip and earl's. currently the system has two pumps, located in the smuggler's box, i took one out to replace, and they feed into one steel line running back to the engine, where it t's off to the left carb and dead ends at the left one.

john (304065), we should catch up some time, with this car in common and our mutual friend peter dawe. i met peter years ago when he tried to revive my motor at road atlanta. six years ago, i asked peter to build my dream car, and during the process we became very close friends. here are some pics of that car. it was all that!
thanks for your thoughts.

[KTL]

Originally Posted by rw7810

Grady - With all respect. I've been running a "dead head" system on my 70 T with Zeniths for 20 years. I tried the recirculating system, but it wouldn't register any pressure. Maybe I was missing something like a restricter in the return line ??

PS: are there any rotary pumps out there any more?? I've been using a Facet Low Pressure Cylindrical Fuel Pump from Pegasus Racing mounted on the front cross bar. Just found this Carter rotary pump and may give it a try.

Carter and Webers

The recirc system needs a restriction (the regulator) on the return side to hold pressure back to the carbs.

There are lots of rotary pumps out there. Holleys (marginally OK), Pierburg, Carter, Mallory, Aeromotive,....... do a search on summitracing.com and you can sort thru the bazillion different bumps.

The Carter link is a nice piece of tech info. But I wonder if their information is correct. TEP says the pump is rated at 4psi and needs no regulator. I have no problem with that if it is indeed 4 psi. But specs on the pump indicate its rated at 6 psi (free flow?).


Carter GP4070 - Carter Universal Rotary Vane Electric Fuel Pumps - Overview - SummitRacing.com

Nonetheless looks like a nice pump. I think for a bit more money we could get a gerotor style pump that is quieter and more reliable. The vane style pump design like the Carter or Holley is a bit dated. I'll shoot some pics of the Holley innards to show what I mean.

The gerotor design is made of meshing gears, similar to the 911 oil pump design.

[hhgt3]

kevin, thanks for help with recommendations on fuel pumps.

i've figured out what gerotor pumps are, thanks to wikipedia.

i've been to summit and pegasus websites and not sure which direction to go, the carter rotary pump or gerotor pumps, and i currently have two pumps, which are facets. and this is for 2-liter track car.

thanks, bob

[KTL]

There's other people who've said those Facet pumps are of questionable reliability. You'd want to confirm what sort of volume the Facet pumps provide since there are many types. Point being is if you only ran one, you might not have enough volume. It could be that two were run in parallel to establish suitable volume.

I don't think you can go wrong with the Carter pump. It's a decent price at $80 and should provide plenty of volume for you. TEP says it can support up to 300 hp. Running one pump will simplify your system too. Because technically two pumps in parallel should have check valves on the outlet line, before they "Y" together, to isolate them from each other.

Be sure to check the condition of the existing braid hose if you plan to re-use some. Braid is just like any other hose- doesn't last forever. Braid actually makes it harder to inspect. Smell it and bend it. If its stinky or cracks when you bend it, it's garbage and needs to be replaced.