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Old July 14th, 2018, 04:51   #1
Fiat500Baja
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Default Fuel pump question?

So I have a Jazz 22 gal fuel cell in my baja...what kind of fuel pump and pressure will I need to use?...I was planning to still use the factory type filter that sits next to the timing cover. ..also I wanted to incorporate some sort of g-surge fuel pump to eliminate fuel starvation when driving at extreme angles. ..the pump I'm looking at supplies 340L/PH...is this pump too much for a ALH?...I just don't know what pressure stock fuel pump runs at.
Thanks
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Old July 14th, 2018, 05:41   #2
jettawreck
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The is no fuel pump pressure up to the filter on an ALH. The injection pump is a suction system from the tank. Some, mostly with major performance mods or failing IP, have added a lift pump from/similar to the PDs to boost fuel delivery and/or compensate for air leaks.
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Old July 14th, 2018, 06:11   #3
Fiat500Baja
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So a cheap regular electric fuel pump for a carb will work for a lift pump, right?

Remember that this in a baja using a non stock fuel tank. ..I thought the stock jetta had a pump in the tank. ...I just wasn't sure what kind of pump pressure that it uses...if it is to just get the fuel to the filter then any 7-8 psi pump should work fine.
Thanks again for your response.
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Old July 14th, 2018, 08:35   #4
AndyBees
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Unless you are running a low tank of fuel or the pick-up tube is not near the bottom of the tank, I seriously doubt that you will ever have fuel starvation issues. If the boost pump picks up air, it will send it on down stream to eventually end up in the injection pump. I do not remember the PSI, but the exit restriction valve from the pump body maintains certain amount of pressure and is located near the top of the pump body which allows small amounts of air to exit without notice. So, if the volume of air is minimal, your engine will never know it. At 70 mph, my Jetta, on average, uses about 2.5 ounces of fuel per mile.

Thus, other than peace of mind, I doubt you're engine will ever need a lift/boost pump. Now, having said that, it would serve you well in the event you run out of fuel and need to pressurize the system while bleeding the injector lines to get the air out. You need a pump that has flow thru characteristics in the event you lose electrical power to it.
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Old July 14th, 2018, 13:29   #5
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Thanks for your help
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Old July 14th, 2018, 18:51   #6
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Sharing ....

The aftermarket fuel tank that I installed in my 84 Vanagon with ALH engine obviously has a high pick-up tube. I've been low on fuel (3 gallons in a 16 gallon tank) and picked up air going through curves fairly fast up hill. It has happened more than once.

Last July, south of Portage, Wisconsin heading to Alaska, I was running low on fuel and looking for a good exit (lots of construction at exit after exit) as I was pulling a small camper. Anyway, going much farther than I felt comfortable, I took the next exit coming up. At the end of the exit ramp, there was a hard right and little ways down the road was another hard right, then a hard left into the service station with one more hard left to the pumps. After filling, the engine would not start ...... sucked air! So, it took me about 25 minutes to get it running (dam diesel everywhere). The tank only held 14.225 gallons.

So, sucking air can be an issue!

Today, I did install a side line (parallel) pump using a check valve. So, it will only operate if I flip a switch under the dash.
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Old July 14th, 2018, 19:21   #7
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Quote:
Originally Posted by Fiat500Baja View Post
So a cheap regular electric fuel pump for a carb will work for a lift pump, right?

Remember that this in a baja using a non stock fuel tank. ..I thought the stock jetta had a pump in the tank. ...I just wasn't sure what kind of pump pressure that it uses...if it is to just get the fuel to the filter then any 7-8 psi pump should work fine.
Thanks again for your response.
No, a "stock" ALH engine and fuel system does not have a lift pump in the tank. Strictly a single suction type pump on the supply side. The fuel pick-up and gauge sender unit fits in the same space as the gasser models with a fuel pump, but the ALH versions had no OEM in-tank pump.
Not until 2004 PD engines and injection systems did a in-tank lift pump make its appearance in the Golf/Jetta/NB models.
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2001 Jetta TDI GLS Silver-current driver (salvage)permanently vented-Panzer Plate-Sprint 520s-ScanGauge-CheckTemp III-ZeroStart heater-CAT 2 filter
2003 Jetta GLS Black w/leather (New Project Car) fixer-upper w/broken TB
2004 Cadillac SLS (wife's)
1999 GMC Suburban (It's MN-you need one)
197? Shibura 2cyl diesel 4WD tractor-loader/brushhog (very handy unit)
196? International TD340 Dozer-w/Drott 4-in-1 bucket/back ripper attachment
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Old July 15th, 2018, 04:01   #8
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Jettawreck, thanks for clearing the air.
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