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Thu Aug 05, 2010 5:54 am

HI I recently put a new electric Carter Pump under the tank of my bug. THe pump runs great but the outets on the pump did not match the outets on the bug. I got 1/4" fuel injection grade fuel lines and they fit the pump tight and nice. The ends that mated to the car were not tight easy to pull on and off. I figured what the heck I will put some screw clamps and all will be well. WRONG!! I got some seepage out of the in and out lines under the gas tank. My wife noticed the smell of gas, so I pulled the tire last night and double clamped the hoses and checked this morning and all is dry.

Not happy and want to get it right, what is the correct hose size.

Thu Aug 05, 2010 6:12 am

Quote: fuel injection grade fuel lines

Injection fuel lines are hard, the clamps can't 'squeeze' on them. You need 'regular' 1/4 fuel line.

Thu Aug 05, 2010 7:50 am

VW never used clamps on their soft lines ( on low pressure systems) ........

Clamps are sort of a later thing that came from that "you can not have a hose connection with out a clamp" mentality ....

Dale

Thu Aug 05, 2010 8:51 am

Worm drive clamps suck. They don't provide a 360 degree seal on small diameter hose, plus the worm has sharp edges that cut into the hose.

You want bolt drive clamps. They provide a 360 degree seal, and they don't cut into the hose:

http://busdepot.com/details.jsp?partnumber=311133515

As for the hose size, 1/4" is wrong. Your beetle wasn't built in Detroit. You need metric fuel hose. 7mm is the size that fits the Carter pump. The hard fuel line size is either 7mm or 5mm depending on what year your car is:

http://www.oeveedub.com/mm5/merchant.mvc?Screen=PROD&Store_Code=oe&Product_Code=N-020-281-1

http://www.oeveedub.com/mm5/merchant.mvc?Screen=PROD&Store_Code=oe&Product_Code=N-020-355-1

If you need to make an adapter, you can use brass barb fittings from the hardware store. 1/4" on one side, and 5/16" on the other. It's not exact, but it fits, and with the proper bolt-drive hose clamps, it doesn't leak.

Thu Aug 05, 2010 9:27 am

And I thought the screw drive was better, ha!! Thanks, I will pick up some 5 mm hose.

I have a lathe so I will make 3 nice brass adaptors from the 1/4 down to the 5 mm -- The 5 mm is actually 1 mm smaller then the 1/4" and that 1mm is big when it is in a dia. --

Thanks guys.

Thu Aug 05, 2010 10:14 am

Actually 1/4 inch is 6.25 mm....... 5 mm is to small and actually closer to 3/16 or .1969 inches....... And 5/16 is actually 7.75mm or .3125 inch.... VW steel fuel line through tunnel is actually 6mm O.D. ...

http://www.carbidedepot.com/formulas-drillsize.htm

Dale

Thu Aug 05, 2010 1:44 pm

Std. 100r7 fuel hose is not rated for efi applications. SAE100R9 spec fuel injection hose is what is needed. Even if you hose did seal, it may not hold. Two clamps on each connection should be more than sufficient on that set up. Clamps were never originally used, but they system wasn't under any kind of pressure before the pump either. Efi is anywhere from 45-65 psi.....you'll need clamps, OR...........go with threaded connections such as AN fittings.

Thu Aug 05, 2010 1:59 pm

Hotrodvw wrote: Std. 100r7 fuel hose is not rated for efi applications. SAE100R9 spec fuel injection hose is what is needed.
Since he's using the Carter pump, I suspect he does not have FI...

Thu Aug 05, 2010 2:03 pm

why the heck did I think he was efi???? wow.....space cadet! :lol:

Thu Aug 05, 2010 3:09 pm

Hotrodvw wrote: why the heck did I think he was efi???? wow.....space cadet! :lol:

Mentally you zeroed in on fuel injection because that was hose type he is using....

Dale

Thu Aug 05, 2010 3:34 pm

Maybe.......I'm curious what designates that they're efi 'grade'.

Thu Aug 05, 2010 3:50 pm

Hotrodvw wrote: why the heck did I think he was efi???? wow.....space cadet! :lol:

Maybe cause you know you want it on YOUR car.. :wink:

Thu Aug 05, 2010 3:53 pm

You're right.......that's my next big thang! :D

Thu Aug 05, 2010 4:02 pm

Hotrodvw wrote: Maybe.......I'm curious what designates that they're efi 'grade'.

EFI grade is certified to 50 psi.... Non EFI grade is certified to 10 psi....

Check out pressure specs on hose next time in FLAPS....

Dale

Thu Aug 05, 2010 4:05 pm

I sell hose for a living Dale......I'm curious if his hose says it, or if it's an assumption, or...... It really doesn't matter, just curious.

Thu Aug 05, 2010 5:06 pm

Hotrodvw wrote: I sell hose for a living Dale......I'm curious if his hose says it, or if it's an assumption, or...... It really doesn't matter, just curious.

What kind of fuel line do you recommend for dual Dells, Eric?

Thu Aug 05, 2010 7:09 pm

Hey Hose boy!!!! Hot Rod VW Guy!! Here is the hose :

6.4 mm FUEL INJECTION HOSE SAE J30R9 MADE IN EU Q-08-022

Hit me with the scoop!!

Thu Aug 05, 2010 7:45 pm

what pressure is the carter pump rated for?

will be curious if the float, needle, and seat can shut if off.

Thu Aug 05, 2010 8:42 pm

bugnut68 wrote: Hotrodvw wrote: I sell hose for a living Dale......I'm curious if his hose says it, or if it's an assumption, or...... It really doesn't matter, just curious.

What kind of fuel line do you recommend for dual Dells, Eric?

If you're talking about std fuel hose for a carb application, run of the mill 30R7 fuel hose will be great......unless you want to step up to the pricey stuff. In California, it may not be available now days due to the CARB Compliant regulations that the nazis down there are mandating. That's a 100R9 spec. The permeation rate and some other garb are different than the 30R7.

Thu Aug 05, 2010 8:46 pm

nextgen wrote: Hey Hose boy!!!! Hot Rod VW Guy!! Here is the hose :

6.4 mm FUEL INJECTION HOSE SAE J30R9 MADE IN EU Q-08-022

Hit me with the scoop!!

J30R9 is the same as the 30R9 spec. It's rated for 100psi, and a 900 psi burst! If you get a 900psi surge, it should handle it. Basically, it's probably the best rubber fuel hose that you can get ahold of legally. :lol: It's reat for these applications:
Gasoline, ethanol extended gasoline, oxidized sour gas, diesel fuel, biodiesel and lubrication oil.