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View Full Version : Too Much Fuel Pressure?



HondaBoy
06-01-2005, 08:23 PM
ok, well i've been having trouble with my fuel filter that's in the engine compartment. i had put a view through one in. then maybe 3 weeks ago i replaced it with another one that had universal fittings. the fittings are plastic that screw into the metal ends on it. anyway, i used teflon tape and tightened the fittings well, not overly tight. it would mainly leak from just one end. dunno why. then today i noticed it leaked from around the part where the glass is sealed with a rubber gasket to the metal end. i tightened that and it didnt leak, but the fitting was still leaking even after i used teflon tape. i even wrapped it correctly, counter clockwise so it wont slip off when its being screwed in. anyway, i decided to say screw it and got a oem type replacement. seemed to fix my problem! so could it be my fuel pump is pushing too much pressure? also can too much fuel pressure cause bad gas mileage? i'm getting between 19-21mpg. i can add a pressure regulator easily. my fuel pump is a replacement pump, not original.

Versanick
06-01-2005, 09:16 PM
an aftermarket fuel pump or bad vacuum pressure can create bad gas mileage. we have, on our fuel injected motors, a return line fuel pressure regulator, not in line like newer hondas (and other cars). My b20a with race cams gets terrible vacuum at some RPM (and way too much at other RPMs) and I run so rich that I could collect the gas leaving the exhaust pipe with a cup. Maybe not literally, but pretty close. If you've fixed the fuel filter leak, you can get an adjustable fuel pressure regulator for maybe $50. That's the return line version. You'll need some parts from Lowe's or Home Depot for the vacuum fittings, but that's not really a big deal.

But definitely, with this type of fuel pressure regulator (I'm assuming you're fuel injected), a bigger fuel pump could easily throw out way too much fuel pressure (and provide RIDICULOUSLY bad gas mileage... you should get way more than 20mpg) An adjustable return side regulator might be in order. I don't know if anyone else knows of a better way to slow down that fuel pump of yours. An inline one isn't far off from being installed, but return works just fine..

A20A1
06-01-2005, 10:35 PM
Was the filter rated for fuel injected cars?

Most clear filters are carbueted fuel systems only... they run about 3 - 6 psi.

HondaBoy
06-03-2005, 05:28 PM
no remember my engine is carbed. i dunno, i put a stock type filter on and no leaks. maybe it was just the plastic fitting was actually too small for the threading? the other fitting was a bit larger that the fuel enters from, it did not have any leaking issues even when i didnt put teflon tape on it. anyway, i think i'll sell it to my friend. he's got a '74 for truck, he'd be up for it. maybe some new O rings to seal the glass would help too. as for bad vacuum pressure giving me bad, i'd thought of that. i found one vacuum leak that i fixed, but i still get sorta bad gas mileage. i drove out to the island last night and it ate up about 1/8 of a tank. that was maybe 30 to 40 miles there and back. i'll check that because i really never checked. anyway, compared to our '02 accord there's a big difference in gas mileage. i did drive going about 70-80 mph most of the way. dunno if that causes bad mileage. i'm just glad i dont drive my friends hemi challenger will a built engine daily. it'll do a nice 11qm, but gets like 5 mpg i think. maybe 8 but i dont think so. right now i'm wanting the better mileage, gas went up about 15 cents like yesterday. oh, the vacuum caps i used were what i'd say are cheapy ones. i cant seem to find quality black rubber ones anywhere.

AccordEpicenter
06-03-2005, 05:35 PM
I think teflon tape degrades when used with gasoline, besides, any quality flare connections (even the banjo bolts etc) you shouldnt use teflon tape with, and if it leaks without it, somthing is wrong with it

A20A1
06-05-2005, 02:53 AM
The trouble I had with some of those clear filters was:
1) Tightened too tight
2) The fuel lines unscrewed the fuel nipples as they settled in.
3) The plastic threads were striped

I did a few things some of which I should have done from the beginning.
1) I hand tightended the filter and did about 1/4 - 1/2 turn with a wrench to finish it off.
2) I made sure I installed the plastic sheild that clips inplace and sort of keeps the nipples from unscrewing themselves.
3) I ditched the plastic and went for brass fittings. one in 1/4" to the carb and the other I think is 3/8" to the firewall.

I always used teflon tape.

HondaBoy
06-06-2005, 09:49 AM
i was going to say brass fittings. i had looked at those last week. looks like that would make a much better fitting that'll last longer. i dunno, i may not go back to the view through filter. the instructions did say to use teflon tape on the threaded fittings. i could always test the fuel pressure with a fuel pressure gauge i can use. as for my gas mileage, its gotten better. but only since i put my 14in prelude wheels back on and took off the ATS wheels my friend wanted me to ride on. maybe its the fact that those ATS wheels weighed about 10 or 11 lbs more each? anyways very noticeable difference in acceleration after putting the lighter wheels on. back to the gas leaking, no more leaks with the stock type filter.

A20A1
06-06-2005, 01:26 PM
Get a fram plastic see thru filter. I used that after I decided not to buy replacement gaskets and filters for the clear view filter. The fram isn't going to leak since the case is sealed but you don't get the replaceable filter element. IMO the clear glass filters don't use that good of a filter.
http://www.3geez.com/attachment.php?attachmentid=3641
You can use this FRAM filer, the pic shows the size of the filter in relation to its packaging... the part number on the box isn't real... I think it was used for a demostration peice. The filter is for domestic cars but the nipples are useable. you may have to run a 3/8" to the carb though which will need a little extra tightening on the clamp. Don't use the stock clamp.
While fram isn't my first choice in filtration for anything... it's relatively hard to goof a fuel filter.

POS carb
06-07-2005, 12:16 PM
make sure the orientation of the filter holder (the rod in the center) is correct, the filter should be squished against the "out" side and then screwed into the "in" side.
I've never had problems with mine leaking, even when I hooked them up to the tranny. use the 5/16 fittings for fuel. They should handle your carb pump no problem. I have one on a 28 PSi Holley

shepherd79
06-07-2005, 04:06 PM
i used clear metal filter, and it was fine on my old carbed accord.
may be you had bad quality filter. i got mine from pepboys i think.