Author Topic: A question about the dark side  (Read 9387 times)

December 24, 2014, 10:57:48 pm

srgtlord

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A question about the dark side
« on: December 24, 2014, 10:57:48 pm »
Not diesel related but still vdub related.  So Ive been playing around with my carb powered vw cabriolet for a good few years now , but I never have been happy with the fuel system I was running. So Im installing an electric fuel pump coupled with a bypass style regulator. Now if I install a 1.5-4psi pump, but the regulator range is 4.5-9psi, will this work??? Will the regulator just not open at all? Would I be better off not using the regulator?



Reply #1December 26, 2014, 12:04:37 am

ORCoaster

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Re: A question about the dark side
« Reply #1 on: December 26, 2014, 12:04:37 am »
srgtlord, I can't see the value of having the regulator at all.  It won't do anything as the pump pressure is below the regulators ability to restrict it.  Max pump psi is 4.0 and Min regulator is 4.5

It won't build pressure and if you do in fact need something like 6.0 on the carb you will need a beefier pump and then regulate it with the appropriate number of turns on what you have as a regulator now.

Gas-----???   Bah Humbug

Reply #2December 26, 2014, 12:27:35 am

TimpanogosSlim

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Re: A question about the dark side
« Reply #2 on: December 26, 2014, 12:27:35 am »
I'm not familiar with mechanical fuel pumps on mk1 VW gassers but the one on my '77 fiat works just fine.

The bowl in the weber fills when the valve is open and when it's full the floats close the needle valve and the unneeded fuel goes back to the tank through the overflow valve.

No fuss, no muss, no worries.

Some of them have electric fuel pumps mounted in the trunk but the electrics don't work any better and have a higher failure rate. *shrug*

Reply #3December 26, 2014, 09:04:20 am

srgtlord

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Re: A question about the dark side
« Reply #3 on: December 26, 2014, 09:04:20 am »
I think my 3 biggest issues with  the mechanical pump I have been running is #1 it came without the required plastic spacer and I ran it that way  #2 there is no return port on the stock rabbit mechanical pump #3 any attempt to go faster than 70mph  was futile as it felt like the fuel delivery was not good enough(this may be due to issues sucking the fuel through the inactive electric in-tank feed pump or vapor lock)




Reply #4January 06, 2015, 09:58:16 am

srgtlord

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Re: A question about the dark side
« Reply #4 on: January 06, 2015, 09:58:16 am »
I purchased a Holley brand 5-7 psi electric pump over the weekend. I figured keeping the the fuel delivery system within the same brand as the Carb would probably help.  I will let you know how it works out

Reply #5February 03, 2015, 01:00:48 pm

air-cooled or diesel

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Re: A question about the dark side
« Reply #5 on: February 03, 2015, 01:00:48 pm »
why not get a regulator @1-4psi? carb float needs a low psi; im not sure but your 5-7psi pump may just push float down and flood carb(at below 70mph), a 1-4 regulator should compensate (?). you ll have low pressure at low speeds, the 4psi may be a limit for higher speeds.or maybe turn that regulator to 4.5 low and see. comes to mind a return to tank would be a +.
« Last Edit: February 03, 2015, 01:05:02 pm by air-cooled or diesel »

Reply #6September 03, 2015, 12:32:34 pm

srgtlord

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Re: A question about the dark side
« Reply #6 on: September 03, 2015, 12:32:34 pm »
I ended up restoring the stock electric fuel pumps and installed the bypass pressure regulator. WHAT A DIFFERENCE!!!!! No more issues pumping all the fuel out of the tank!!! Drove it like this for about 4 months. Hopefully this will help someone out.

 Unfortunately(Or fortunately depending on how you look at it :D ) I sold the car for a measly $500. I just grew too tired of having to replace items the previous owner neglected. I was not prepared to dump another $2500 into replacing the top , fixing the windshield rust, and getting the car repainted.