Fuel Tank Vent Line
Discussion
I suspect my vent hose has become blocked as I can't add fuel without it bubbling back out of the tank. I want to blow out the line but I'm not sure how to get to the hose.
At the neck end, it looks like the the side panel that holds the light and speaker should come off if the two screws (one above the speaker and one just below the parcel shelf) are removed. But it doesn't budge and I don't want to force it. Are there more screws or a trick?
Where does the tank end meet connect to the tank? I had a quick look while working on the brakes and didn't see where if connected. Is it connected to the tank near the filler neck or the far tank?
At the neck end, it looks like the the side panel that holds the light and speaker should come off if the two screws (one above the speaker and one just below the parcel shelf) are removed. But it doesn't budge and I don't want to force it. Are there more screws or a trick?
Where does the tank end meet connect to the tank? I had a quick look while working on the brakes and didn't see where if connected. Is it connected to the tank near the filler neck or the far tank?
Thanks - I'll look for the 3rd screw.
The overflowing is a "new" problem. However, the car sat-up for 3 years before I replaced the clutch and I've been adding sips of gas as I have been getting it back on the road. A couple of weeks ago I added 4 gallons which "disappeared" (but not on the driveway). The 4 gallons went right down the neck with no problems. Now the tanks are empty and very nearly empty. I thumped them when I was underneath working on the brakes but don't remember which one was completely tinny/empty.
I tried adding fuel from a can and a pump. Same thing: After less than a 1/2 gallon, the filler neck was full up to the flapper valve which is 3-4 inches down the filler neck (which cut off the pump). I stopped adding more fuel but fuel (in the 'empty' tanks) expanded up the neck until it over-flowed down the side of the car. I slammed the cap back on which stopped the over-flow. After a wait, I could repeat the exercise.
The car was on a level drive and turned off. The fuel (in the can anyway) was ambient and the outside temperate was normal. I'd say that rules out the car's fuel pump doing something weird as well as some massive fuel expansion. And with the tanks being empty, it wasn't just an overflow.
I experienced a similar problem with EVAP system on my other car. The fuel backed up in the neck and cut off the pump unless you trickled it in (fill-up took 20+ minutes). Having replaced the charcoal canister, purge valve and solenoid (that's pretty much everything to replace) with no improvement, I blew out all the lines with 100 PSI of air and that seemed to resolve the problem.
I'm going to (carefully) run a wire/rod down the neck and confirm that there isn't a physical jam - dead mouse - in the filler tube and try blowing the lines to see if any of that helps.
On a more positive note, after standing in line for an hour, I got my registrations renewed - fully street legal again!
The overflowing is a "new" problem. However, the car sat-up for 3 years before I replaced the clutch and I've been adding sips of gas as I have been getting it back on the road. A couple of weeks ago I added 4 gallons which "disappeared" (but not on the driveway). The 4 gallons went right down the neck with no problems. Now the tanks are empty and very nearly empty. I thumped them when I was underneath working on the brakes but don't remember which one was completely tinny/empty.
I tried adding fuel from a can and a pump. Same thing: After less than a 1/2 gallon, the filler neck was full up to the flapper valve which is 3-4 inches down the filler neck (which cut off the pump). I stopped adding more fuel but fuel (in the 'empty' tanks) expanded up the neck until it over-flowed down the side of the car. I slammed the cap back on which stopped the over-flow. After a wait, I could repeat the exercise.
The car was on a level drive and turned off. The fuel (in the can anyway) was ambient and the outside temperate was normal. I'd say that rules out the car's fuel pump doing something weird as well as some massive fuel expansion. And with the tanks being empty, it wasn't just an overflow.
I experienced a similar problem with EVAP system on my other car. The fuel backed up in the neck and cut off the pump unless you trickled it in (fill-up took 20+ minutes). Having replaced the charcoal canister, purge valve and solenoid (that's pretty much everything to replace) with no improvement, I blew out all the lines with 100 PSI of air and that seemed to resolve the problem.
I'm going to (carefully) run a wire/rod down the neck and confirm that there isn't a physical jam - dead mouse - in the filler tube and try blowing the lines to see if any of that helps.
On a more positive note, after standing in line for an hour, I got my registrations renewed - fully street legal again!
Update - I got the side panel off (missed an now obvious screw). Got the two side hoses off and blew them. I sounded the tank with a stiff wire. Hissing back through the neck on the small one and fuel splashing out of the neck on the bigger one. Best I can tell, the tank next to the filler is actually full. Sure thumps like it's empty, So that would explain where my 4 gallons went and why it bubbles out. No idea what is happening with the far tank.
Looks like I may have another problem with the car acting like it has run dry on starting. Went out and made two stops. After the first stop, it started on the first turnover. 2nd time I had to wait a couple minutes. Suspect it's an undefined fuel issue.
I also played with the fuel sender. The gauge moves from over-full (when I cross it with a jumper) to under-empty (wires disconnect from the sender). Across the sender (indicating a 1/3rd tank) is reading 0.094 ohms (meter set to 2K scale). Any idea what the resistance should read?
Anyway, it looks like a new sender will be needed. Any ideas the parts number or values for a fuel sender for a VDO? I see some on eBay but don't know if they would be compatible. Didn't see anything on the parts sticky.
Looks like I may have another problem with the car acting like it has run dry on starting. Went out and made two stops. After the first stop, it started on the first turnover. 2nd time I had to wait a couple minutes. Suspect it's an undefined fuel issue.
I also played with the fuel sender. The gauge moves from over-full (when I cross it with a jumper) to under-empty (wires disconnect from the sender). Across the sender (indicating a 1/3rd tank) is reading 0.094 ohms (meter set to 2K scale). Any idea what the resistance should read?
Anyway, it looks like a new sender will be needed. Any ideas the parts number or values for a fuel sender for a VDO? I see some on eBay but don't know if they would be compatible. Didn't see anything on the parts sticky.
Edited by Grady on Tuesday 25th April 23:07
Edited by Grady on Wednesday 26th April 01:05
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