Lessons learned during fuel filter change
Le Mans Master
Joined: Mar 2001
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From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
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St. Jude Donor '12
Mine is somewhere between a 16 and 17MM flare and a 5/8 & 11/16 SAE.
As you can tell I tried to get mine off over the weekend. My 16MM didn't fit, my 17 fit but as I applied tourque to it it started to round the nut. So I tied my SAE open ends and nothing seemed to fit. I'll have to wait a few weeks until I can get it on a friends lift, drop the cat on that side and see if we can get that darned thing off
As you can tell I tried to get mine off over the weekend. My 16MM didn't fit, my 17 fit but as I applied tourque to it it started to round the nut. So I tied my SAE open ends and nothing seemed to fit. I'll have to wait a few weeks until I can get it on a friends lift, drop the cat on that side and see if we can get that darned thing off
Le Mans Master
Joined: Aug 2004
Posts: 5,141
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From: Metairie Louisiana
That's a new one on me, too. When I changed mine, I unscrewed the gas cap to de-pressurize the fuel in the tank.
Second, I pulled the fuel pump fuse.
Next, I started the engine and let it run until it ran out of fuel.
For safety's sake, I then disconnected the battery to negate the possibility of introducing a spark under there via accidentally contacting the knock sensor heat shield, the starter solenoid wiring, etc... with a wrench.
By the time I loosened the fuel line fitting, only about 1/4 of a cup of gasoline came out. I was easily able to manage the rest with a shop towel.
Second, I pulled the fuel pump fuse.
Next, I started the engine and let it run until it ran out of fuel.
For safety's sake, I then disconnected the battery to negate the possibility of introducing a spark under there via accidentally contacting the knock sensor heat shield, the starter solenoid wiring, etc... with a wrench.
By the time I loosened the fuel line fitting, only about 1/4 of a cup of gasoline came out. I was easily able to manage the rest with a shop towel.
The correct way to do it.
Thread Starter
Drifting
Joined: Aug 2006
Posts: 1,326
Likes: 18
From: Los Angeles California
http://forums.corvetteforum.com/show...el+filter+ring
This thread reveals that the flare nut is supposed to be 16mm and the fuel filter nut is supposed to be 20 mm. Some good info in there too.
Okay, now I'm really scared that I'll start having a fuel leak. Was the '96 supposed to come with o-rings on the filter? How do I go about making sure the connection doesn't leak?
This thread reveals that the flare nut is supposed to be 16mm and the fuel filter nut is supposed to be 20 mm. Some good info in there too.
Okay, now I'm really scared that I'll start having a fuel leak. Was the '96 supposed to come with o-rings on the filter? How do I go about making sure the connection doesn't leak?
Safety Car
Joined: May 2006
Posts: 4,290
Likes: 140
From: Salem NH
I put my health at risk by trying to change the filter with gas flowing out of the line at full flow. I had a catch can to capture the fuel as it fell out, and while I was fiddling with the flare nuts, some of the falling gasoline splashed out of the can and into my eyes. This forced me to take an hour-long-break while the can overflowed onto the ground, as I flushed out my eyes with water and called the poison control center for advice. After that I wore goggles and finally found something to cap off the fuel line.
I think the old one was the car's original fuel filter, because those flare nuts were practically welded in place. Some guys get lucky and their filter just spins right off, and they come in here and post that the job is easy, but that is not the case for everyone. One of the flare nuts got deformed a bit and the old fuel filter was completely misshapen by the time I got it off due to how much force was needed. Getting the new filter on was just as much of a pain because the flare nuts had to be just right to keep fuel from dripping out. My O-Rings were nowhere to be found but eventually I got the dripping to stop without them (does this mean it's sealed well enough?)
The whole time I was trying to tweak it to make it stop leaking, gasoline was soaking its way all down my arm and through my shoes into my feet. It burned like hell and I'm now covered in first degree burns. This was by far the most painful and traumatizing job I've done on the car, because I did it this way. So remember, the lesson is, do not try to swap the filter while the gas is siphoning, even if other people on here tell you that they did it successfully. You might not be able to do the swap nearly as quickly or easily as they did depending on the condition of your flare nuts and your accessibility, and in the meantime you will be getting a chemical burn. So put the car down, jack it up differently and try another angle.
I think the old one was the car's original fuel filter, because those flare nuts were practically welded in place. Some guys get lucky and their filter just spins right off, and they come in here and post that the job is easy, but that is not the case for everyone. One of the flare nuts got deformed a bit and the old fuel filter was completely misshapen by the time I got it off due to how much force was needed. Getting the new filter on was just as much of a pain because the flare nuts had to be just right to keep fuel from dripping out. My O-Rings were nowhere to be found but eventually I got the dripping to stop without them (does this mean it's sealed well enough?)
The whole time I was trying to tweak it to make it stop leaking, gasoline was soaking its way all down my arm and through my shoes into my feet. It burned like hell and I'm now covered in first degree burns. This was by far the most painful and traumatizing job I've done on the car, because I did it this way. So remember, the lesson is, do not try to swap the filter while the gas is siphoning, even if other people on here tell you that they did it successfully. You might not be able to do the swap nearly as quickly or easily as they did depending on the condition of your flare nuts and your accessibility, and in the meantime you will be getting a chemical burn. So put the car down, jack it up differently and try another angle.
ROTFLMAO...
Wow!
You got chemical burns from gasoline? Hrmm. Thats rather strange.
-- Joe
Team Owner
Joined: Jun 2001
Posts: 26,196
Likes: 0
From: Orlando FL
St. Jude Donor '08-'09
sheesh that sucks...
the L98 is easy to swap out. In and out in 20 mins maybe?
A rag around the end of the fuel line lasts long enough to soak up any gas (which just does a fast drip on our cars and doesnt run out like you experienced)
Even after all the sucky labor, its still more gratifying than paying someome else to do it IMO
the L98 is easy to swap out. In and out in 20 mins maybe?
A rag around the end of the fuel line lasts long enough to soak up any gas (which just does a fast drip on our cars and doesnt run out like you experienced)
Even after all the sucky labor, its still more gratifying than paying someome else to do it IMO
Burning Brakes
Joined: Aug 2004
Posts: 1,110
Likes: 1
From: Geneseo Illinois
St. Jude Donor '06
Reminds me of a similar story:
i went to change the fuel filter. got underneath the car (parked in my garage) which was on jackstands, 1/4 tank gas, the fuel pump fuse pulled, the cap off to relieve any pressure, and when i got the connection off, gas poured all over me, by the time i could get out and back under with a container to collect the gas, it was pooled all over the place. i could just envision the car going up in flames and the house with it. Never again!
i went to change the fuel filter. got underneath the car (parked in my garage) which was on jackstands, 1/4 tank gas, the fuel pump fuse pulled, the cap off to relieve any pressure, and when i got the connection off, gas poured all over me, by the time i could get out and back under with a container to collect the gas, it was pooled all over the place. i could just envision the car going up in flames and the house with it. Never again!
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Thread Starter
Drifting
Joined: Aug 2006
Posts: 1,326
Likes: 18
From: Los Angeles California
Is that a valve that opens and closes the fuel line from flowing? You are a genius. Out of curiosity, why not put one on both ends?
Last edited by LouisvilleLT4; Aug 13, 2007 at 04:04 PM.
Race Director
Joined: Feb 1999
Posts: 12,772
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From: Indianapolis IN
My car has braided fuel line so it is not a big deal.
Summit and Jegs have these in stock, they are a little pricey but well worth the money.
Safety Car
Joined: Feb 2005
Posts: 4,721
Likes: 1
From: Beautiful Down Town "SWINDLEHURST" Long Island NY
This may sound ridiculous-ly stupid, but after pulling the pump fuse -- start / run till it stalls ---- then remove the 4 screws holding the gas hatch --- and pull the hose to the pump.
Race Director
Joined: Dec 2002
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From: SCMR Rat Pack'r Charter Member..Great Bend KS
Race Director
Joined: Jun 2004
Posts: 13,969
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From: WI
I have changed the filter on mine, it was not a problem. Some gas does come out but only very little before the threads seal. Leave a rag wrapped around the line.
Race Director
Joined: May 2000
Posts: 17,101
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From: No more yankee my wankee, the Donger is tired!
Best statement in the thread.
But changing a fuel filter should not be a life changing experience.... unless you catch your *** on fire. If you have gas leaking out and you've capped off the line, put a pan down until it leaks all the fuel out of the line.
But changing a fuel filter should not be a life changing experience.... unless you catch your *** on fire. If you have gas leaking out and you've capped off the line, put a pan down until it leaks all the fuel out of the line.
CF Community Team
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I just changed mine today and saw this thread. At least on the 85 you have to unplug the fuel pump relay on the driver's side firewall or it will run and pump gas when it sees the drop in fuel pressure, even with the key off.
Thread Starter
Drifting
Joined: Aug 2006
Posts: 1,326
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From: Los Angeles California
The 1996 definitely does not do that. Press the schraeder valve for a bit and all that pressure will be gone.
Race Director
Joined: Sep 2000
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From: The Top of Utah
Originally Posted by capevettes
I just changed mine today and saw this thread. At least on the 85 you have to unplug the fuel pump relay on the driver's side firewall or it will run and pump gas when it sees the drop in fuel pressure, even with the key off.
That is totally bogus. First, the fuel pump relay is 100% controlled by the ECM. When the ignition is first turned on, the ECM powers the fuel pump relay for 2 seconds. Then, only after the ECM receives pulses from the distributor, indicating that the engine is turning (cranking or running) does the ECM again power the fuel pump by closing the fuel pump relay. Nowhere is there a fuel pressure sensor. The fuel pump relay never "sees the drop in fuel pressure" with the key on, or "even with the key off". The same is true of the ECM. There is nothing on a C4 that reports fuel pressure, and nothing to receive or react to such input.
RACE ON!!!
Thread Starter
Drifting
Joined: Aug 2006
Posts: 1,326
Likes: 18
From: Los Angeles California
I finally found out why my new fuel filter has been leaking. Found an o-ring on the ground near where I've been working. Reluctantly, I decided to take the filter off again, but THIS time I pinched the fuel feed line on the fuel tank. Took two minutes, and what a difference! Only a few drops of gas came out after I loosened the filter. My wrenches also seemed to fit much better this time, or maybe it was just the fact that I wasn't freaking out because of fuel flowing down my arms. Overall it took about 20 minutes to take it off and put it back on this time, and it went beautifully, simply because I prepared this time.
After looking at the detached lines for a while I finally located the other O-ring, so I put the one that I found on the ground on a similar place on the other line and it sealed right up. I'm glad I got to experience this job from the perspective of those for whom it went really well.
After looking at the detached lines for a while I finally located the other O-ring, so I put the one that I found on the ground on a similar place on the other line and it sealed right up. I'm glad I got to experience this job from the perspective of those for whom it went really well.
Team Owner
Joined: Oct 2004
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From: altered state
St. Jude Donor '05
Did mine in about 10 minutes, lost maybe a cup or so of fuel tops..
Jack the pass side up only (plese use stands), remove gas cap and goto town. Fuel should pool up on the DS of the tank so it doesnt siphon down to you. Having less than a half tank helps.
Make sure and get a wrench on the filter ends when loosening/tightening your lines so you dont twist/kink them or youll be hating life.
Jack the pass side up only (plese use stands), remove gas cap and goto town. Fuel should pool up on the DS of the tank so it doesnt siphon down to you. Having less than a half tank helps.
Make sure and get a wrench on the filter ends when loosening/tightening your lines so you dont twist/kink them or youll be hating life.