DoBeR

iTrader: (1)

I plan on doing this tommorow, i did it on my other car a couple years ago but it was in a different spot. Anyways, when I undo and remove the old filter, will gas keep pouring out of the line or will it dribble a bit than stop. Should i have something around to plug it or am I not going to loose that much gas???

Trevor K

You can "bleed" the fuel system by pulling the fuse for your fuel pump and turning over the engine.

Then when you go to undo the lines there should be next to nothing inside.

DoBeR

iTrader: (1)

Do I have to do that?? What if I just unhook the line and change the filter?

AJ_92RS

You don't "have" to do it.

Do you enjoy fuel with 40+ psi behind it spraying all over you, including your eyes? That's what will happen.

The fuse is located by the battery. It's a little black sleeve (may or may not have a cover) with a 30 amp fuse in it. Unhook it, then start the car. Let it run until it dies. Then, just to be sure, crank it over 1-2 more times.

*EDIT* OH!!! Take off the fuel cap first. It'll help.

DoBeR

iTrader: (1)

Where near the battery is this fuse you speak of??? My Haynes manual said the fuse was underneath the dash so I took it out and started the car but all it did was make it run like crap. The fuel pump was still working.

v8unleashed

iTrader: (3)

what you did was probably shut off one of the injectors

i couldnt ever find a fuse under the hood (where it was supposed to be according to haynes and everybody here) when i replaced mine, but there was some kind of fuse or something underneath, right near the gas tank, and the car died when i unplugged that


you'll lose a half gallon or so of gas from it running out.....so dont use the same container you use to change your oil and waste all the gas like i did

DoBeR

iTrader: (1)

Well I found the fuse it was right behind the headlight in front of the battery. Cover said it had a 10 amp fuse in it but when I opened it it was a 20 amp. Anyways I undid it and the car died and I went to do the filter. I sprayed the threads earlier with penetrating oil because they were rusty. I put the wrenches on it and tried to undo it and the damn fuel line twisted. Now I have to take the damn thing to a shop and get them to change the filter and replace some of the lines. What a pain in my ***!

19doug90

geeze all i did was pull off the cap for my gas tank....little bit of fuel came out but nothing that bad...undid the two nuts pulled the old one out popped the new one in...tightened it all up and was good to go.

AJ_92RS

TBI or TPI?

19doug90

tpi why

AJ_92RS

The fuel line must have lost pressure somehow.

Regardless, I'd still relieve the pressure first. Why take the chance?

v8unleashed

iTrader: (3)

19doug, you have NO IDEA how painful gasoline is when it gets in your face...maybe you left the car sitting for a long time, maybe your pump is bad, maybe G0d was nice to you....anyways, i would suggest relieving the pressure next time before you open it all up

RJR99SS

also, you may have quite a bit of trouble just getting the fuel filter out.

The type of filter on f-bodies has two flared fitting that screw into each side of the filter. The fittings are 16 mm, and the filter is 20 mm. You NEED TO USE A FLARE NUT WRENCH ON THE LINE FITTINGS. Dont be surprised if the fittings dont come loose either, they can be pretty solid. You can try to tighten and untighten it over and over again to losen it up.

The even bigger problem is rust. Depending on what shape your car is in, the line fitting can actually rust up BADLY. I've seen it where the fitting would actually deteriorate so much that a 16 mm flare nut wrench would strip it, while a 15 mm on wouldnt even fit on. In situations like that all i can recomend is to file it down until a smaller wrench can fit on it.

When you reinstall the filter, be sure to put it on the right way. There will be an arrow on it indicating the flow direction.

19doug90

Maybe.....i have had mixed results when asking wether taking off the gas cap vents the entire line or just the tank. So basically i cant explain why i didnt have 40 psi of fuel spraying out but oh well that as it may be i did have fuel run all down my arms which burnt like i have never experienced before from a liquid therefor making the pulling the pump fuse being a good idea because you wont have as much fuel in there....

Viprklr

iTrader: (5)

Why? Just cut the fuel line with a tubing cutter and put in new line with a compression fitting. A little extra work but it'll save you the $50+ the shop will charge you.

v8unleashed

iTrader: (3)

That's kind of like saying....... if you're changing your spark plugs and one of them breaks off, no problem, just pull the head.

TomP

I tend to disagree a bit here... This comes from my experiences with rusted-up brake lines. Sometimes (as was just mentioned in the case of 16mm/15mm sizing), even a properly sized flare nut wrench can strip the tube nut!

If you feel the wrench starting to strip the tube nut, as would happen only with a rusted-up or overtightened fitting, STOP and get yourself a BIG- as in 12" or 15"- open ended adjustable wrench. Use the wrench on the tube-nut, and be sure to use it the correct way.

Seems odd to be able to use an adjustable open-ended wrench incorrectly, but it's possible. You want the brunt of the force to be against the fixed jaw of the adjustable wrench. It's a bit hard to explain in words, so I drew up a picture using a photo of a large Craftsman adjustable wrench. I'll attach it below. The adjustable jaw is only meant to take up the "slack" in the wrench; the force should mainly be against the fixed jaw (as noted by the red lines).

It seems that the large wrench, with it's long handle and thick jaws, has a tendency to break the fitting free easier. The long handle gives torque, and the thick jaws resist side-loading of the fastener. Remember too that you should always use a quick/hard force on the tool instead of a slow/"pulling" force. A slow and pullllling (or pushhhing) force can side-load the fastener and cause it to strip out. Hard-fast "yanks" will simulate an impact wrench, and jar the fitting free faster.

Another couple of suggestions for changing your fuel filter: 1, put goggles on. Ever see a Ford Mustang fuel filter? It's up "behind" the rear bumper, so, you got it, your eyes wind up directly below the filter. Way to go Ford!! On our cars, goggles would prevent fuel spray from blinding you. 2, put your wrenching arm through a black garbage bag to prevent gasoline burns. 3, never do this job inside, or with a hot exhaust nearby. 4, never drop any tools near your job- dropping a wrench onto concrete CAN cause a small spark! [edit] 5, I like to smear some anti-sieze compound on the threads of the tube nuts, AND on the ends of the tubing (where the tube nut rotates on to prevent rust.

6. Make sure the little o-rings are still on the extreme ends of the inlet/outlet tubes!! Sometimes these can get stuck in the old filter. If you put the new filter on and one/both of these o-rings are missing, your fitting will leak.

Fun fact (well, not so fun for me): On my first (original) AC/Delco pump, I never depressurized the system with any fuse. I'd remove the cap, undo the filter- never got a fuel spray- and wait until the gas slowed down and stopped dripping. Usually it would stop just as I started to panic. But, with my second and third (both Borg-Warner) pumps, the fuel NEVER stops dripping. Never! So there's definately something different internally with a AC/Delco pump then a BW (pep boys) replacement pump.

Viprklr

iTrader: (5)

This is why. The fuel line is already twisted. At least part of it needs to be replaced.

TomP

Isn't tubing fun? Something to keep in mind if you guys ever touch your brakes- http://www.classictube.com (and some other companies) make brake tubing in stainless steel! I've snapped a few lines on my rear disc axle, and always patched them by hand with a flare tool- but no more. When I get my rear disc axle back in commission (posi blew- really an Eaton gov-lock locker that destroyed itself), I'm buying the SS lines. Nothing more frustrating then "Alright! The nut broke free" and then feeling "Snap" as the tube breaks.

DoBeR

iTrader: (1)

I got the car taken to the shop today and they gave me the safety certification and changed the fuel filter for 20 bucks which im happy with. Id rather pay 20 bucks canadian than spend my time dicking around with rusty gas line. Oh well thx for all the info guys maybe next time I try to do it, it wont be so bad.

19doug90

sounds like a recipie for busted knuckles =)

25THRSS

yes, take these guys advice and make damn sure the pressure is released. It's painful enough when it runs all down your arm and starts to burn your skin. I can't imagine getting it on your face.

oldblueZ

Well, I know what you guys are saying about relieving the pressure, but I've disconnected my fuel filter and fuel lines many many many times before with the lines still pressurized. You just have to aim the spraying gas away from you while it depressurizes.

About getting fuel all over you....umm, you are doing a fuel filter, you get fuel down you arms and all over the place.

Later,
Jesse

Jon92TA

I changed my fuel filter in a garage and found out how strong gas fumes are up close. I put a big fan behind me to blow the fumes out which helped a lot.
I unplugged the fuel pump wiring in the back and did a quick start/die to relieve pressure.

TomP

That's why usually it's better to pull a wrench towards you. And hopefully we've all got some form of Mechanix gloves by now (I have the M-Pact series... I remember when they used to be blue, instead of black ) The quick/hard motion of using a wrench is also why smacking the wrench with a hammer works- it's a quick/hard motion. Although tools usually aren't tempered to handle hits from a hammer; chrome is brittle; be sure to wear goggles to avoid any chips being thrown into your eyes. And obviously don't hammer on anything near the fuel filter - spark = explosion!


That's why I mentioned putting my arm through a black garbage bag... at least that way I still have some hair and skin on my arm when I'm done with the filter

blackgold84

iTrader: (1)

where is my fuel filter?

hi my name is retard.

lg4 motor

Dr G

Blackgold84 see the below pic:-

From this thread:- Underbody Pics
https://www.thirdgen.org/techbb2/sho...uel+filter+pic

Hope that helps you!

Patrick305

Hi guys,

I prepared this with a good effort:

1. Read both Chilton's and Hane's manuals
2. Read tech boards on F-body sites regarding fuel filter replacement
3. Tried/ did everything everybody said.

But did not succeed.

Fuel line kept on leaking...about 1 gallon before I called it quits.

What I did:

1. Relieve fuel pressure to avoid spillage /prolong leakage

2. My fuse box has 2 fuses with FP (fuel pump) inscribed. Took them out before starting the engine, like they said. Unscrewed fuel cap. Started the engine. Ran a few minutes. Never stopped:

- 1 20 amp fuse with FP/Fan inscribed (took it out)

- 1 10 amp fuse with Inj. 2 /FP inscribed (took it out)

3. In another try, did what a guy said to take out the fuse contained in the black sleeve located just facing the battery and pinned clearly on the fender/side (passenger). Of course, this turned off the engine. But did not stop the leak.

4. Put on back fuel cap. Did not work to stop leakage.

5. Took out, also, to test, 10 amp fuse inscribed inj. 1: stopped the engine /didn't stop the leakage

6. Mine's got an in-line type filter (round stainless steel housing)

Please speak out / Thanks!

Patrick Cyr
'88 coupe 305 TBI Camaro

blackgold84

iTrader: (1)

sorry and thanks that help great, i need to keep remembering to do those searchs, i try...

Patrick305

I'm reading more and more that even with fuel line depressurised, gas drippings still's going to happen and continue on and on. If it's normal and usual, well darn it, I'll do that way....! Thanks for your replies and keeping you updated...

blackgold84

iTrader: (1)

are all the step the same that i should be doing if i am going to swap off my carb, the fuel line taking it off and putting it on another carb. i will be starting another post about this but with more questions just wondered if i take the same steps though?

getting a new performer 1406 and performer dual plane manifold

85firebird

Since the fuel filter is located below the gas tank, and the line to the tank is filled with fuel, fuel will continue to run through the line even after the pressure is relieved. To stop this natural siphon, you could try forcing the gas back into the tank. Maybe with compressed air ?

AJ_92RS

For some reason the siphoning effect doesn't apply here. I'm gonna guess because there just isn't enough suction from the fuel leaving the fuel line to draw the fuel up high enough in the pickup tube.

I dunno why for sure. All I know is I've done 3 and even had one tank out, but never had that problem.

85firebird

I replaced my fuel filter a few days ago, and learned a couple of things.

1) One way to relieve pressure is to disconnect both the fuel pump relay and the lower of the two oil pressure sensors. (The top sensor sends info to the gage, while the lower sensor serves as a back-up to a faulty fuel pump relay. If the ECM detects oil pressure (engine turning over) and the ignition switch is in the ON position, it will route power to the fuel pump if the fuel pump relay hasn't done so already.) Then turn engine over; it will only fire for a second or two.

2) Rusted or overtightened fuel filter fittings require some serious torque and/or impact to break loose. I had to lock a pair of Vicegrips on one of the line fittings so that the handle would immediately hit the underside of the car as soon as I applied force (torque to loosen) on the fuel filter. A block of wood was placed between the car floor and the filter. I took a piece of 2X4 that was an inch longer than the distance from the floor to the handle of the Visegrips, and I wedged it in there HARD. The 2X4 is almost vertical now: it holds the Visegrips securely against the floor of the car. At this point you can manhandle the fuel filter without the risk of twisting the fuel line out of shape. It also allows you to use impact on the fuel filter. The nut on the fuel filter is 20 mm (a wrench which I don't own), so I used a 21 mm open-end wrench. Playing on the looseness of the 21 mm, I could now give torsional impact on the filter nuts which are big and tough enough to resist rounding.

Nate86

I also had the same experience as 19doug90. My friend and I changed the fuel filter as soon as I had bought the car and when we took the vacuum hose off of it, the line only dribbled a small amount of fuel out. We did not relieve the pressure at all.

However, the car had only about 1/8th tank of gas left, and it had been driven only twice after I bought it (the guy I bought it from said the car was sitting there for a couple of months in his yard). I suppose that might have had something to do with.

Regardless, I appreciate this information. I will be more careful next time around.

TheMysticWizard

iTrader: (1)

Fuel Filters on a TPI are just not fun, Make sure the pressure is relieved, as I made the mistake of doing one without relieveing the pressure, it sucked.

Even with the pressure out of the equation it was still a chore, I had gas down both arms to my sholders, and about a half gallon down the driveway.

Couldn't get the new threads to start, take you time with them, mine kept wanting to start cross threaded, but I could tell because they wern't going together smoothly.

I don't want to have to replace it again any time soon, if ever. It was seriously one of the worst jobs I've done.

racindaelky78

Yes the fuel burns when its on fire,i work with the stuff daily and i have had it spray everywhere and not once has it had a burning sensation,it was warm but not enough to provide discomfort, but drain the lines before you do this,and jiffy lube now does fuel filters, just goes to show its real easy to do.

UNCLE TOM

iTrader: (1)

been reading this thread . did i miss something ? with all the hidden fuses why not just disconnect battery ? seems to me this would be easiest when changing fuel filter . oh , it just came to me . you will have to go through the hassle of re-setting clock . seriously any reason this will not work ??? just remove gas cap and disconnect battery , change filter and reconnect . feedback please .thanks .

UNCLE TOM

gray89vert

iTrader: (3)

i just did mine about a week ago. all i did was spray some penetrating lube on the lines....sprayed it again...and again...and the nuts broke free. gas came out at a steady flow as i thought it would so i had my car jacked up really high so i could fit a gas can under there... got the old filter off and put the new one on...not a bad job at all took about 10 minutes and maybe maybe lost 1/10 of a gallon of gas.

19doug90

what theyre trying to do is turn the motor and have the fuel empty from the lines but have the motor die, theyre saying to disconnect the fuel pump fuse but i thought the fuse was just to get the pump running then it pretty much goes on its own? i dont know, but thats what theyre trying to accomplish so theres no fuel in the lines when you open them up

Zenroth

iTrader: (1)

I think the simplist way of doing this is just to disconnect the electrical harness underneath the car that runs to the fuel pump. Turn the key over once with it connected to pressurize the system, turn key off, pull connector. Start car, let it die. I had to do fuel filter awhile back and it was a pain. Ended up having the lines twist vs them unscrewing. Tubing cutter to the rescue though.

slackett1

Am I missing somkething....

I have spent a lifetime around fuel. Starting tinkering with lawn mowers as a kid...

For the life of me, I can't ever remember it ever burning my skin. I've had it drip, pour, sprayed on me...prolly swallowed a gallon or two in my lifetime siphoning out tanks. Never felt anything.

As for releiving fuel pressure, heres what I do:
-Cap off
-Go under car and pull the connector for the pump (over the rear end)
-Turn it over...let it run til it dies...if it even starts
-pop the hood and wrap a towel around the schrader valve and press a small screwdriver to let that pressure out

As for siphoning I did learn a trick while changing my fuel pump. I had just filled my tank...imagine that. I disconneted the return line and put a bucket under it....30 minutes later it stopped and presto, there was only 3 gallons left in the tank.

bfox88

iTrader: (2)

never got it on your face around and in your eyes then.

Jproz1167

iTrader: (3)

Six steps to changing your fuel filter successfully!

(Step one) Buy fuel filter
(step two) drop car off at meachics shop
(step three) wait till car is fixed
(step four) go rent some movies
(step five) go get beer & order pizza and by the time you get home pizza will be there
(step six) enjoy you achievement while you relax in a recliner

raven0840

Gasoline, brake parts cleaner, and acetone (there's others, but those are the ones I've been around) all will burn sensitive skin. I.e, face, underside of arms, etc. But they'll burn scratches too, if the scratch is deep enough. How do I know? well...on the LU-5 the fuel filter has rubber hoses. And the filter is located in the engine compartment. And if you drive aggressively, sometimes the rubber hose will rest against the exhaust manifold, since there isn't (or at least I couldn't find) a bracket to hold it away. So when said rubber hose falls against the manifold...My first thought was "Oh, that's where that gas smell is coming from". Incidentally, this was yesterday so I had a pile of firecrackers sitting behind me in the car too...I just about WAS the show last night...

Anyway, rubber hoses...I pulled the 10amp fuse from the block, ran the car till it died on its own, turned it over a couple of time to be sure. Gas was still leaking out of the hole, so I did two things: 1. Wrapped a towel around the rubber hose before the filter and clamped a vise-grip on the towel to pinch the line closed 2. held the hose up high enough to prevent any back-drainage from the TB's. I'm thinking if the engine is hot, back-pressure builds up within the system without the fuel pump turning on cuz I still had a decent leak after I pinched the line closed. After I held the hose higher than the tb's only air came out and eventually the pressure went away. After I fixed the leak, I checked the hose (~25 years old) carefully for damage from the Grips, didn't see any. But if you only have hardlines on your car...I guess you could fab a plug from an old peice of line, like from a junkyard or something, use a fem-fem connector to screw it on...maybe...and hook the filter up to the other line first.

jb3829

iTrader: (1)

I just changed mine and it was pretty simple although I think you should start it first then pull the fuse allowing it to die. I pulled the fuse first and it wouldn't turn over so I removed the filter and the fuel would not stop coming out! I lost almost a quart of gas before I got the new filter on. It doesn't sound like much, but when you're on the garage floor trying to get this thing back on its a pain! BTW, the fuse on my 91 RS is between the battery and the coolant tank on the passenger side. I sprayed the filter connections with sea foam deep creep and they were easy to loosen. Hope this helps

Ghettobird52

im about to do this and going to attempt the connector above the rear end that people have noted about. will post about its results. little scared!!!

Ghettobird52

Went great!!! unplugged that connector on the body of the car above/behind the rear end , took off the gas cap and turned it over a couple times and no pressurized gas at my face! was alot of drippage but luckily i had the towel and a cup readily available! 16/20 open ended wrenches worked fine!

little foot

Why can't you relive the pressure from the Schrader valve on the fuel rail? put a rag over it and poke it with a screw driver.

JRobling

For reference: