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Discussion Starter #1
I finally got to drive my Spider Jr. again after a long layoff and it took quite a but of cranking to fill the Weber's bowls enough to get the car started. It took at least a dozen tries, no longer than 5 seconds each to avoid frying the starter. Is this normal for a car with a mechanical fuel pump or is it a problem with the carbs?

I'll probably update to an electric fuel pump at some point but I'd rather not mess with it if its working. There's plenty of other work that needs to be done.
 

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Discussion Starter #3
I should have said that this happens anytime the car sits without use for more than a week. Just this time it took longer to get it started. Of course its been more than 3 months since the last time it ran.

Some more possibly useful info, the car is a low mileage 69 (~30k) and while the carbs were cleaned by the PO the fuel pump has never been serviced.
 

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Trained (ex)Professional, , 1953-2018 RIP,
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The fuel level in the bowl will drop over time thru evaporation and/or leakage and it will take the mech fuel pump a little time to refill the carb(s). Try 15-20 seconds crank time before allowing the starter to cool off. The cat's *** setup is to have an electric pump at the rear of the car (with an on/off switch) feeding the mech pump up front. Turn on the key, flip the switch and let the electric pump fill the carbs.
 

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Discussion Starter #5
Why not just go full electric and bypass the mech fuel pump? With my low voltage ouput at idle (generator) I might have some problems but then again it doesn't need to supply much fuel at idle.

So basically sounds like this is normal. I was worried that either my carbs were missing gaskets or my fuel pump diaphram was about to fail and have little desire to end up on the side of the road at some inconvenient time.
 

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MitchW said:
Why not just go full electric and bypass the mech fuel pump?
Ahh. Good question. On a non-concourse car I would bypass the mech pump but since I'm gonna show the '68, it's there to satisfy the judges :D
 

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Well dagnabbit, the pure mechanical setup worked when new; why does it not work now? I've 27 miles on the odometer since completing my Duetto restoration. My first significant problem was getting her started, and that problem persists. My setup is includes restored Gordon Raymond Webers; rebuilt original mechanical fuel pump from Then and Now; rebuilt original FISPA filter/regulator with new filter, rubber diaphragm, gasket, and seal; all new metal and rubber fuel lines from tank to carbs; new fuel tank; and a new in-tank pickup and sending unit. The fuel lines between carbs, from carbs down to the FISPA, and from the metal main line to the pump are clear to enable fuel flow visualization. All clamps are correctly sized and double checked tight. My problem is the mechanical pump won't push any fuel up to the FISPA during cranking or initial start, so she starts and runs until the carb(s) run out of fuel. There's no fuel moving in the clear lines. If I pull the top of the back carb and fill it with gas, she'll start and run; if I rev her immediately, sometimes fuel begins to move, albeit with plenty of air bubbles, and sometimes, not. Once fuel is moving, I can drive her for miles, including in stop and go traffic, without issue. But if fuel won't move on initial start up, it will die when carb bowl fuel supply is exhausted. This problem occurs after sitting overnight; or for just a few hours. Yesterday, after extended idling, hot engine, in the garage, a faint knocking sound appeared from the front of the car, idle slowly decayed, and she died. Restarted no problem. No knocking sound. Initially. It then returned a minute or two later, and the idle decay, followed by engine stall, process repeated itself. Gave up, grabbed a beer, called it a day. Went out this morning, she started up instantly, and idled until the fuel in the bowls ran out, then died. No knocking sound. No fuel evident in the lines, and the FISPA is half full. I'm about to give up and buy an electric pump, but the factory setup worked as designed. What am I missing here?
 

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Mitch: I had the same issue after more than 1 week standing, and I placed an electric fuelpump, as Jim suggests, in the rear, actuated by a push button. After more than 1 week of standing, I fill the carbs with the electric pump, and then it starts!

Jim, any chance that there are air bubbles in the lines? Alternatively, did you try without the fuel filter? This to find out if there is an issue with the fuel filter.
 

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I did early on in the initial start up stages, and it was partially blocked, that is what led me to rebuild the FISPA. The filter element is new and clean. I have a spare mechanical pump (a repro, not an original) I will try that next.
 

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I keep it original,..... since I drive it about once a month, just get a 60ml syringe, 6 inches of weed wacker fuel line and take the wing nut cover off the top each carb and give it 20 to 30 ml of gas. Will start right up.
 

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Rafael before swapping pumps, I bypassed the FISPA filter regulator and went straight to the carbs. Good solid flow, no bubbles. I removed the FISPA, completely disassembled and cleaned it (again), put it all back together, and now it appears to be working as designed. Time will tell. Thanks!
 

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Mechanical fuel pump

I am having similar problems with my fuel pump. After the car has been sitting for more than two weeks, the mechanical fuel pump will not deliver any gas at all. I noticed that there is no gas in the fuel lines and maybe that is where the problem lies. Perhaps, the mechanical pump does not suck air, it needs fuel nearby in order to function properly. Does this make any sense, or should I take up plumbing?

Cheers, James
 

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Well dagnabbit, the pure mechanical setup worked when new; why does it not work now?
Goldarnit, those mechanical fuel pumps worked OK in 1966 when our cars were driven daily, but now that they have become toys instead of appliances and only get used weekly, it's a problem. Going electric is a good solution.

just get a 60ml syringe, 6 inches of weed wacker fuel line and take the wing nut cover off the top each carb and give it 20 to 30 ml of gas.
This is a good solution too. It also encourages you to do a visual inspection of the engine compartment and check the oil / coolant / brake fluid while you've got the hood open to squirt the gas. It's a bit harder to do with sidedraft carbs, but works well on downdrafts.

I just realized that Mitchw started this thread 10 years ago!
 

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Goldarnit, those mechanical fuel pumps worked OK in 1966 when our cars were driven daily, but now that they have become toys instead of appliances and only get used weekly, it's a problem. Going electric is a good solution.
Well I am happy to report progress...she sat one week after my latest attempt to resolve the problem, started right up and ran no problem on the mechanical pump. I may eventually let her sit for two weeks and see what happens, but not until Winter as Autumn is primo driving time here in 'Bama.
Roll Tide.
 

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Problem returns

Well, after sitting one week, she started up fine but a minute or so later when the gas in the rear carb was exhausted she died and would not restart. I filled the rear carb and she started right up, flow was good again through the lines with air bubbles initially, then they were gone and the flow was solid. I've ordered a FACET pump and am considering Papajam's setup of feeding the stock mechanical pump with the electric pump.
 

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Hi there,

So, I'm not the only one with this starting problem! My '82 Spider 2000 (twin Solex carbs) also requires some effort after having stood for a week or so. I've been thinking about an electric pump but first have to consider the following before getting started:

- What type of pump for the 2,0 l engine?
- Electric pump just to start then switch off and let the mechanical pump take over? What about if one forgets to switch it off? What type of switch?
- How about doing a full electric pump conversion, i.e. take off the mechanical pump? In this case, the pump will come on as soon as the ignition is turned on. What about fuel regulation and bypass back to tank?
- Where is the best place to tap power from to run the pump? Would it require a separate circuit and fuse?

Lots of questions. Maybe somebody can point me in the right direction or to an old thread covering the subject?

Cheers,

Marc.
 

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- use an electric pump intended for feeding carbs (lower pressure and no return line needed)
- use a pushbutton; it stays on as long as you press the button with your finger
- you can do that, however for safety you should also install a device that switches the pump off when the engine stops. You don not want to be in a car accident while the pump stays pumping fuel through a broken fuel line.
- if you install the pump close the the tank, you will have to make a wire from the fusebox to the pump. You can therefore use an existing fuse, especially if the pump is only to fill the carbs before the mechanical pump takes over.
 

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I used Papajam's concept and installed the Facet low pressure pump to feed the mechanical pump, so no need to remove and block off the mechanical pump. Simple installation and she starts right up now after sitting.
 
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