Occasional fuel smell
07-25-2008, 11:21 PM
#1
Junior Member
Thread Starter
Join Date: Jul 2008
Posts: 2
Likes: 0
Received 0 Likes
on
0 Posts
Occasional fuel smell
hello,
I recently had the ignition coil go on my 1996 f-150 LB, 5.0. As part of the repair, i had the serpentine belt, distributor cap, rotor, plugs, wires, air filter, fuel filter, pcv valve, oil changed, radiator flushed and an issue with the secondary air injection taken care of also.
The truck is running fine, and other than some of the worst corrosion slowly eating away at the under side of the vehicle, it is running great, getting better gas mileage than ever etc.
Before and after the repairs i have had some co-workers tell me, that they can smell gas around my vehicle. both in the mornings after i arrive and in the evening (after it has been sitting all day). I never really notice it.
My boss happened to have a meter of some sort that is used to detect gas leaks...not really for gasoline, but it does detect it. I put the sensor over the open gas cap and it read around 102...not sure what 102 means but when in open air it reads 0. After crawling around underneath the truck with the probe i was able to get a consistent reading of 20-30 on the top of the front tank where the fuel lines and wires enter the tank.
I noticed some staining on the side of the tank coming from the top that could be fuel. i could smell a strong odor in that area. I don't really notice a "loss" and since the tune up gas mileage is better than ever.
But the smell is there and according to the meter, there is definately some vapor escaping the top of the tank....the fuel lines were replaced before i bought the vehicle..(most likely since the old ones were probably corroded, i've relaced the brake lines over time due to corrosion too) They look fine and the 90 degree elbows are shiny and silver from what i can see of them.
I am unsure of how these lines and wires enter the tank....is there a gasket or some kind of grommet that could be dry rotted? as far as corrosion on the tank, it appears good...i believe they were originally replaced with the fuel lines. the brackets holding them up are a different story....the front one is severly corroded and is flaking heavily....I doubt from the look of the bolts, that they can be removed without breaking.
What kind of costs am i looking at here, what are the names of the parts i might need, is this possibly a do it yourself job? (the tune up etc has burned a nice hole in my pocket...lol)
any thoughts would be appreciated
I recently had the ignition coil go on my 1996 f-150 LB, 5.0. As part of the repair, i had the serpentine belt, distributor cap, rotor, plugs, wires, air filter, fuel filter, pcv valve, oil changed, radiator flushed and an issue with the secondary air injection taken care of also.
The truck is running fine, and other than some of the worst corrosion slowly eating away at the under side of the vehicle, it is running great, getting better gas mileage than ever etc.
Before and after the repairs i have had some co-workers tell me, that they can smell gas around my vehicle. both in the mornings after i arrive and in the evening (after it has been sitting all day). I never really notice it.
My boss happened to have a meter of some sort that is used to detect gas leaks...not really for gasoline, but it does detect it. I put the sensor over the open gas cap and it read around 102...not sure what 102 means but when in open air it reads 0. After crawling around underneath the truck with the probe i was able to get a consistent reading of 20-30 on the top of the front tank where the fuel lines and wires enter the tank.
I noticed some staining on the side of the tank coming from the top that could be fuel. i could smell a strong odor in that area. I don't really notice a "loss" and since the tune up gas mileage is better than ever.
But the smell is there and according to the meter, there is definately some vapor escaping the top of the tank....the fuel lines were replaced before i bought the vehicle..(most likely since the old ones were probably corroded, i've relaced the brake lines over time due to corrosion too) They look fine and the 90 degree elbows are shiny and silver from what i can see of them.
I am unsure of how these lines and wires enter the tank....is there a gasket or some kind of grommet that could be dry rotted? as far as corrosion on the tank, it appears good...i believe they were originally replaced with the fuel lines. the brackets holding them up are a different story....the front one is severly corroded and is flaking heavily....I doubt from the look of the bolts, that they can be removed without breaking.
What kind of costs am i looking at here, what are the names of the parts i might need, is this possibly a do it yourself job? (the tune up etc has burned a nice hole in my pocket...lol)
any thoughts would be appreciated
07-25-2008, 11:26 PM
#2
No Pain, No Pain!
Welcome to the board, smac!
I can't really help you with your problem, only to say that we have some good mechanics, on the site, and they should be able to offer some sound advice.
Good luck!
I can't really help you with your problem, only to say that we have some good mechanics, on the site, and they should be able to offer some sound advice.
Good luck!
07-26-2008, 12:24 AM
#3
Senior Member
Welcome to the site!
Not sure what you meant by 'open gas cap' but the carbon canister is intended to absorb these types of fumes. If the gas cap were indeed off and the sniffer were close to the filler neck, would expect a decent vapor level bordering on the explosive limits.
Four thoughts come to mind on the gas tank - either the tank has corroded through on top, or the gasket between the tank is leaking, or the sending unit/fuel pump assembly has failed, or the new hose connections were not made up correctly.
All issues require access to the top of the tank to assess. One way is to drop the tank, another is to remove/lift the bed - either way is not pleasant and will depend on the availability of related equipment and sheer grunt-n-groan muscle.
Guessing that the 102 is in parts-per-million - essentially saying it was sniffing 0.0102% gas fumes - not too much below the lower flammability limit of 0.014% for that specific sampling point.
IMO, free-air gas fumes are not good, and it would be worthwhile to identify and eliminate them.
Not sure what you meant by 'open gas cap' but the carbon canister is intended to absorb these types of fumes. If the gas cap were indeed off and the sniffer were close to the filler neck, would expect a decent vapor level bordering on the explosive limits.
Four thoughts come to mind on the gas tank - either the tank has corroded through on top, or the gasket between the tank is leaking, or the sending unit/fuel pump assembly has failed, or the new hose connections were not made up correctly.
All issues require access to the top of the tank to assess. One way is to drop the tank, another is to remove/lift the bed - either way is not pleasant and will depend on the availability of related equipment and sheer grunt-n-groan muscle.
Guessing that the 102 is in parts-per-million - essentially saying it was sniffing 0.0102% gas fumes - not too much below the lower flammability limit of 0.014% for that specific sampling point.
IMO, free-air gas fumes are not good, and it would be worthwhile to identify and eliminate them.
Last edited by wde3477; 07-26-2008 at 12:26 AM. Reason: doggone grammar and counting fixes!
07-26-2008, 08:21 AM
#4
Junior Member
Thread Starter
Join Date: Jul 2008
Posts: 2
Likes: 0
Received 0 Likes
on
0 Posts
I'm sorry, what i meant by "open gas cap" was that i removed the gas cap to take a reading at the filler neck, so that i could have "base" reading of unrestricted gas fumes to judge any results i found with the meter.
thank you for your quick response. what are the parts involved in the top assembly of the tank. assuming the gas lines are okay and the tank is ok. what else is involved with that connection?
I've been told the same thing, about lowering the tank or removing the bed. I am hoping to get an idea of cost and difficulty of replacing the parts making the connection at the top of the tank, before i try to do either.
With limited knowledge, never having removed a tank or a bed, limited tool access if anything goes wrong, am i better off leaving this to a professional at $65/hr?
That is why i was hoping to determine the part costs involved. I can't seem to find any online documentation on how that assembly is made. I don't know if there is one piece or 30. Plus i'd love to know the names of any of the associated components so i can talk apples to apples with any mechanics as i try to figure out how to deal with this.
Thank you again for all your help.
thank you for your quick response. what are the parts involved in the top assembly of the tank. assuming the gas lines are okay and the tank is ok. what else is involved with that connection?
I've been told the same thing, about lowering the tank or removing the bed. I am hoping to get an idea of cost and difficulty of replacing the parts making the connection at the top of the tank, before i try to do either.
With limited knowledge, never having removed a tank or a bed, limited tool access if anything goes wrong, am i better off leaving this to a professional at $65/hr?
That is why i was hoping to determine the part costs involved. I can't seem to find any online documentation on how that assembly is made. I don't know if there is one piece or 30. Plus i'd love to know the names of any of the associated components so i can talk apples to apples with any mechanics as i try to figure out how to deal with this.
Thank you again for all your help.
07-26-2008, 11:11 AM
#5
Senior Member
Join Date: Jun 2008
Location: Independence MO
Posts: 116
Likes: 0
Received 0 Likes
on
0 Posts
Lowering the tank is not a horrable job to do if you have two people. At least yours still runs, get it down to E for a weekend. Have one person prime the pump, turn key to run and back, and look for a line leak. It may be splashing out due to a bad or loose pump seal. The pump mounts to the tank about like a garbage disposal seals to the sink. Ring turns and locks in. To pull the whole tank, remove the filler neck, unplug the pump, then it should just be two bolts on the tank straps.
