fuel lines - nightmare part 2

MYBAD79

MYBAD79

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I worked on this fuel line setup for 5 hrs today and got nowhere.... let's start with the parts I'm using:

Holley fuel pump, 80gph, shiny chrome....
http://store.summitracing.com/partd...840140+4294925239+4294891547+115&autoview=sku

The pump does not have an internal regulator or a return line connection, therefore I bought this regulator:
http://store.summitracing.com/partd...400178+4294925239+4294880914+115&autoview=sku

The regulator is advertized to be adjustable from 4 1/2 - 9psi... I installed a pressure gauge between the regulator and the carb and it shows "0" .... adjusted the regulator (assuming that the setscrew on top is the adjuster), no change.... took the gauge out and blew into it... shows 3 psi.... gauge works.....

After some research in a few catalogs and online I found out that this regulator is a "non return" style.... It appears that the pressure on the two outlets is the same.... great.... does that mean that the pump is pumping 80 gph right back into the return line because on that side of the regulator is less resistance (no filter, no gauge) .... ??

I've had nothing but leaks using stainless tubing with aluminum fittings and adapters, getting ready to order hose ends and use SS braided hose only, no more tubing.... hose and aluminum only....

"Rant on"
The hose ends that I need for this with a few 90's and one 180 degree ellbow are $80... that's more expensive than 25' of SS braided hose ...
"Rant off"

BTW, everything was just fine with the stock pump...... :banghead::banghead::banghead::banghead:
 
Don't you love when a good plan just grenades right before your very eyes :suicide: I have that problem a lot myself. BUT i am quite positive that in the end you will WIN :noworry:
 
I'm not following, because the pump has no return you bought a non return style regulator??????
 
Twin_Turbo said:
I'm not following, because the pump has no return you bought a non return style regulator??????
Click to expand...

I did not pay attention when buying the regulator. I guess that's part of the problem :crap:

The pump does not have an internal regulator so when I found this one in the catalog I was convinced it's what I needed.
The info in their catalog is misleading at best (IMO) - this regulator is right next to the Holley pumps and for some pumps it says "a regulator is required"
 
Karsten, most of what I know, I learned the hard way....

learned from a boat I had, that aluminum for vibration/engine related shit is VERY bad, will take the vibration a little bit then...SHATTER, like glass at the stress point, I didn't believe what I was looking at, called a old ME I worked with and he just laughed....saying yes, happens ever time....so I would be very nervous with any aluminum anything on the end of the fuel pump hose, much less the rest of the car...

Second, I can't imagine why you are using any mechanical fuel pump, I personally have had very marginal results with them and prefer a electric pusher from back near the tank....the adjustable reg up front is fine....
I find with electric pumps, like the CARTER unit, you have no issues with any return lines, the fuel is under slight pressure up forward, so perk issues are non existent.....under suction from a mechanical pump, they ARE a issue I never bothered to get all technical and figger out WHY on a car I had some years ago, I just went the CARTER pump in back and fuck it....it works, case closed....never a problem since then....make sure you have a oil pressure switch in there to stop the fuel if you wreck....

Other than looks, I can't see the reason for all this braided fuel line crap, I could see it on the DPFI boat I modded up, because of fire and USCG/BIA requirements, but not on a car....the braided lines are so much stiffer than rubber, they transfer any engine vibration to the chassis fuel line,

Best of luck man....:thumbs:
 
I have used those regulators in the past and found that after a while, they are all over the place.

I also have a non return fuel pump and made my own return flow regulator that works just fine, and can't screw up.
A block of steel with the 2 main 3/8" carb lines (brake line) brazed to it. A short beaded 1/4" beaded tube stub brazed to it also to make a tee. This stub was filled solid at the open end with brass. Then I drilled a hole (.035") I think as a flow control orifice for the return. Drill to any size to regulate pressure.
Sort of crude and simple, but keeps the pressure at approx 4psi. Also threaded a schraeder valve to block to use with a real fuel pressure test gauge like shops use to test FI.

You could also use your present setup and just put a fitting with a plug and oriface in the return line to regulate flow. Just use the present regulator as a tee.

ReliefReturn.jpg


If you try this, drill to recess the tubing first, before brazing/silver.
 
I can't help you with your fuel set-up but I do know from experience that if you tell summit their catalog was misleading, they will pay return shipping on the item, sometimes it's easier to just let it go because you don't want to pay return shipping on an item for a tiny refund, but if they pay it, get your money back.
 
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figure out what you need and I might be able to save you (or anyone else) some money...100% brand new and all genuine Aeroquip....I`m a little confused why you need the regulator or the return line...unless I missed the part about your having fuel injection...

IMG_1511.jpg
 
Update:

I got it done. I tapped the inner diameter of a 3/8" NPT fitting to M12 (hole is about the correct size) and put a bolt in there... then cut the bolt flush with the fitting and drilled a 3mm (roughly .120") hole thru the bolt - homemade plug/reducer.... works good so far :smash:

At one time I was close to just throwing this whole chrome junk out and keep using my stock pump. I cut the 3/8" supply line to install a tube compression fitting for a -6AN hose. Was going to the same for the return line which is 1/4".... Come to find out that there is no compression fitting for 1/4" that adapts to -6AN. I'll have to braze a short piece of 3/8" tubing on the 1/4" tube and the use the same fitting as I used on the supply line. When I braze the tubing on the return line I'll find out if the pump is really empty... I blew air thru it and it's out of the car for over a week now...

21498edaaa9450f.jpg
 
MYBAD79 said:
...I cut the 3/8" supply line to install a tube compression fitting for a -6AN hose. Was going to the same for the return line which is 1/4".... Come to find out that there is no compression fitting for 1/4" that adapts to -6AN. I'll have to braze a short piece of 3/8" tubing on the 1/4" tube and the use the same fitting as I used on the supply line...
Click to expand...
I did the same thing Karsten but I bought a 1/4 compression fitting down town and then bought a reducer from http://www.anplumbing.com/shop/index.php. I can't remember if the other side of the compression fitting was -4 or -5 (and I can't find my original invoice) but I either used #991906 -4 to -6 reducer or part #991907 -5 to -6.
 
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