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fuel cell ??s part deux

gary

Well-Known Member
so my fuel cell is in, and hooked up, and working, sorta...the truck hesitates under acceleration right now. i'm thinking the carb needs to be adjusted to match the new fuel pressure by the new electric pump...yes or no? i messed with it a bit at first, thought it was okay, but the hesiation is still there...seems like maybe there's not enuf fuel in the carb to handle the pedal geting mashed...
are all electric fuel pumps noisy? mine ticks continuously, although once in a while it will quiet down. is this a sign of not enuf fuel in the pump, to keep it lubed while it's working in there?
i'm questioning the pressure, because although i did the lines the way i was told, i'm not sure they're right. coming out of the tank is an 8AN fitting (the bulkhead, that also attaches to the pick up tube), reduced to a 6, then reduced to a 4, that converts to a male 5/16 hose fitting. that hose runs thru an inline filter, then all the way to the carb. fuel pump is Facet name brand, from mckenzies. it's supposed to put out up to 4 psi. there 's no external regulator...not supposed to need one. all smog lines/canisters are plugged, i think. no issues there, that i know of. 88 toy, 22r carbd
any help or opinions are greatly appreciated
 

vwguy

Well-Known Member
first off unless it has a built in regulator you need one
4psi sounds low that may be the problem you have to remember the rating is max that is why you need a regulator
i.e. if i had a carb that need 4psi constant i would want a 6-8psi pump and would want to regulate it to 4psi
another thing is we have that pump on our buggy and it gets quieter the same way you describe when the pressure builds up like it slows down because no fuel is being burned
the size of your tubing seems fine with the 5/16 no worrys there
was this problem present befire you made the change to all the aftermarket stuff


how ironic is it that most people slow down for speed bumps yet almost all of us here im sure pin it
 

gary

Well-Known Member
truck was fine before...stock fuel tank and stock fuel pump (not electric). i have no idea what the carb requires for pressure...anyone know what a stock toy carb needs, or where to find that out? i wondered that myself, if 4 was enuf, but i don't know. interesting.....
does a regulator require a return line to the cell?
 

ntsqd

Well-Known Member
4 psi is about what Webers want. Likely it's too low for the stock carb. I'd guess more like 5-8 psi. The pump gets quiet when the needle seats on the seat and shuts off fuel flow. If you hear it working, you're drawing fuel. I have one of those pumps on my 'glass buggy to prime the bowl since it sits for long periods. My mechanical pump can draw thru it, so I see it as a back up pump. It came off of an Alfa GTV road racer that had two of them in parallel on it, and still wasn't enough.
I'd look into an inline pump. There are low pressure pumps similar to the injection pumps, but with carb pressure output. Typically the Holley pumps are real noisey.
Set up a return line and use that pump to go floatless.

TS

"Teach you all I know and you're still stupid"
-- Howdy Lee
 

gary

Well-Known Member
just for reference, mckenzie's also offers a cater pump, 0-7 psi. does that sound better? i don't wana disassemble the carb, cuz it has to be smoggable again eventually....
 

vwguy

Well-Known Member
i would go for the other pump

how ironic is it that most people slow down for speed bumps yet almost all of us here im sure pin it
 

jim_moulton

Well-Known Member
Put the stock fuel pump back on. The facet pump will feed fuel to the stock pump. One nice thing about facet pumps is that you can pump thru them when not powerd up. If this doesn't fix the problem, check the vacuum advance hose to the distributor. You don't want to remove this. Also make sure the hose isn't cracked or cut. Hope this helps.
 

rdc

- users no longer part of the rdc family -
maybe while moving and changing the lines, a real small piece of dirt got into the acell pump...maybe look down the carb throat and see if it's squirting when you gas it......

race trash wiring
 

gary

Well-Known Member
after playing with it for a few days, here's where i'm at. by opening up the air/fuel mixture screw on the carb, the truck no longer hesitates...not sure if that's good for the carb though. this has made the pump tick continuously...it doesn't go away, kinda like there's no back pressure in the system to keep the pump full. looks like a new pump is in the works. i'm looking at Holley, because i'm told their quality is better than a Carter, plus one of the choices is available with a regulator. however, it's a more powerful pump than i seem to need. i called LC Engineering, toyota specialists, and they told me the carb probably requires 4-6 psi. so here's the questions...

any good or bad impressions of Carter fuel pumps? (0-7 psi)
or
do i get the big Holley, and regulate it down to my needs (kinda seems like overkill on the pump, although the regulator will make it usable for me) (14 psi)
or
the next step down Holley, which says it does not need a regulator...it has an internal regulator/spring loaded pressure measuring system, and i can add a regulator later if i need it (7 psi)

thanks again....
 

gary

Well-Known Member
my local kragen has a performance center, and it just so happens that they had the holleys. i bought the bigger one, though i'm still not sure it's what i need, for cheaper than anywhere i've seen so far (summit, jeg's mckenzie's), so i guess that's the plan. this one comes with a regulator. i get to plumb a return line from the regulator back to the cell, which doesn't seem too hard. i've still got flow questions. the pump i got says it's pre set at 14 psi, and it will flow 110 gph. says at 9 psi, it'll flow 70 gph. how much less at the 4 or so i need? the other holley is pre set at 7 psi, flows 97 gph. at 5 psi, it flows 67 gph. seems like it might flow more at the 4 psi i need. HELP HELP HELP...
 

vwguy

Well-Known Member
just figure out the ratios of each and see which is better

how ironic is it that most people slow down for speed bumps yet almost all of us here im sure pin it
 

gary

Well-Known Member
i went with the carter-had the best flow at my required psi. now there's a new issue...maybe a little too much pressure to the carb...there's NO fuel visible in the float bowl window. is it possibly pushing too much fuel through the carb, keeping whatever valve open, not allowing it to close, and fill up the bowl it's running fine, just seems weird......
 
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