Refueling Problems - Fuel Filler Neck Obstruction?

[Vainglory, Esq.]

Lately I have been having what seems like a unique problem with my '70 Charger.  When I put gas in, rather than flowing smoothly into the tank, it accumulates in the fuel filler neck.  Note that this is a fairly newly-installed tank and filler neck, so there might be some problem with the installation.

However, I'm interested to know if anyone has had or heard of this kind of issue before.  Do you think there is some obstruction in the fuel filler neck?  How would I go about determining what that obstruction might be?  Any tips or tricks that I might use short of dropping the gas tank?  I'd like to avoid a major project if at all possible. 

[472 R/T SE]

Is it properly vented?

[Vainglory, Esq.]

Is it properly vented?

It should be, but I realize that isn't a very satisfactory answer.  I guess I should check to see that the vent tube hasn't been pinched...

[Rolling_Thunder]

my filler used to do that...   it would fill the neck and then drain into the tank slower than the pump would fill...        never figured it out -  it only happened when the pump was a fast flowing pump though...   when the pump was a little slower it never was a problem...        I know my tank was properly vented at the time...   no idea otherwise...   

[Just 6T9 CHGR]

Nothing really in the tube that would cause a restriction (unless someone did you dirty....if so then you should invest in a locking cap)

Like others suggested make sure the vent tube isnt plugged but honestly I dont see that being the problem since the tube is vented near the top anyway.

I always have to fill my tank pretty slow (at the first click max).  If I let it go any faster, she backs up 

[1969chargerrtse]

Nothing really in the tube that would cause a restriction (unless someone did you dirty....if so then you should invest in a locking cap)

Like others suggested make sure the vent tube isnt plugged but honestly I dont see that being the problem since the tube is vented near the top anyway.

I always have to fill my tank pretty slow (at the first click max).  If I let it go any faster, she backs up 

Yeah mine too. 

[resq302]

Nothing really in the tube that would cause a restriction (unless someone did you dirty....if so then you should invest in a locking cap)

Like others suggested make sure the vent tube isnt plugged but honestly I dont see that being the problem since the tube is vented near the top anyway.

I always have to fill my tank pretty slow (at the first click max).  If I let it go any faster, she backs up 

Yeah mine too. 

I do the same thing.  I do notice however that when it gets full, even on the slow fill, that it backs up in the filler tube and when you take the pump nozzle out, you can see the fuel level drop in the tube.  A couple factors that could be contributing towards your problem: try having the filler neck side of the tank higher than the pass side if the slab at the gas station is slanted, park to your advantage (you'll actually get more gas in the tank also.),  try the slow fill method and see if that solves your problems,  try filling in the morning when the gas is at the coolest temp, this way the fumes are less likely to cause the evap system in the fuel nozzle to click off thinking the tank is full, and finally, try running a wire snake down the tube and see if there is any restriction.  With the last suggestion, I would make sure that you have no sharp edges on the wire or any hooks so it doesn't snag onto anything like your fuel sending unit.

[Troy]

I don't remember having that issue on any of my 68s. My Power Wagon is horrible though. Probably takes 45 minutes to fill both tanks.

Troy

[hemi68charger]

The vent tube runs from the top of the filler neck tube where it meets the quarter panel and dumps off into the inner framerail next to the filler neck tube. I seriously don't think it plays into the filling process since it doesn't even touch the tank and the pump nozzle is more than surely pass the exit point of the filler neck tube. It's main function would be venting when the gas cap is closed.
I have always had this issue with all my 2nd generation Chargers and I've owned them for over 30 years now. I never leave the pump on auto. Sometimes it is the position of the nozzle outlet in the filler tube. I always hold mine such that the tip of the nozzle is against the outboard side the filler tube, not just sitting in there. It is a pain in the butt, but sure beats having to clean all the fuel spillage off the quarter.  2nd Gen's............. nature of the beast.............. Maybe back in the day the pump volume wasn't as much as it is today.

[ITSA426]

I have the same issue with one of my chargers.  It fills by the thimbleful and can easily take a half hour to top off from empty.  Really annoying on road trips.  Don't know why but it's done it since I got it all back together.  No obstructions or obvious problems.  No problem when filling from a gas can but I hate to drag one of those along to use at the pump.

[hemi68charger]

From my experience with 30 years of this, it's nozzle end position in the filler tube and the rate of fuel discharge. I have got it down now were I can fill it up at a fairly good rate, but keep an ear for the sound when she's getting full (you'll have to know your car) and then back off some.......

[CharcoalCharger]

My buddy sits there with the nozzle, too, when filling his '69.  As was stated here before, you can't leave it on auto.  I'm sure it wasn't just Chargers.  My '74 Dart I have to keep an eye on, too.  It is way too easy to get gas all over the side of the car.  I have to do, as hemi68charger states, and listen for when it is getting full, then back it off to top it off.  Sometimes it's a pain, but in the end...it's worth it. 

[Old Moparz]

Never had that problem on my Charger.   






But then I've never put gas in it either. 

[Vainglory, Esq.]

Thanks for the responses, everyone.  I'm thinking I'll have to try to "fill it up at an angle" trick.  I'm honestly hoping that this is not an obstruction in the filler neck, and nobody "did me dirty" like 6T9 mentioned.  That's my biggest fear at this point...

[hemi68charger]

Thanks for the responses, everyone.  I'm thinking I'll have to try to "fill it up at an angle" trick.  I'm honestly hoping that this is not an obstruction in the filler neck, and nobody "did me dirty" like 6T9 mentioned.  That's my biggest fear at this point...

John,
I sent you a reply PM. But, you may wish to stick a wire down the filler neck to see if there's an obstruction. If noone here posts it, I can get the length of the filler neck. This way you can cut off what you need, insert it into the filler neck and see if it bottom's out or hangs up prior to what should be it entering into the cavity of the tank...

Troy

[model maker]

My 68 used to do that when it was getting close to full. I would bounce the rear quarter up and down a few times and would hear a GURGLE and she would  start to fill again. I always thought it was  a trapped air bubble. I would bounce the car a little as she was filling up and noticed when i did that, the backup wouldn't happen as much.
Bert

[hemi68charger]

John.
Here's the tank end of the filler neck.. If something is lodged down there, it'll clog things up for sure.......... It's not a direct filler neck diameter passage as you can see........

[A383Wing]

my 70 has never been able to take full on gas refill....usually takes the slow setting on the handle....and it also will gurgle when getting close to full....

[bobs66440]

Wow! It seems like this is a chronic problem with these cars. I can fill mine ok but if you let it fill until it trips the nozzle shut-off, there will be gas shooting out of the fill pipe.   Must be a design flaw?

[model maker]

I was convinced it was trapped air, then all of a sudden BLURRP gas all over the side of the Charger

[freddyd02]

Sorry to bring up an old topic but having read the problems you guys are talking about maybe back in the 60s when they were designing the car the fuel pumps back then pumped at a much slower rate than now a days? The engineers might not have thought of future pumps pumping faster. Or they did think of it and said "Shoot these cars are only gonna be around 10-15 years" 

[Hemidog]

I've never had any problems filling with the gas nozzle fully open on my 68 at any angle  Maybe the fuel pump/nozzle is different in Norway, but I fill up my tank fairly quickly.

[kab69440]

I don't remember having that issue on any of my 68s. My Power Wagon is horrible though. Probably takes 45 minutes to fill both tanks.

Troy

So was mine. I think it had a lot to do with that 90 degree bend two inches behind where the fill nozzle sits.

[Dino]

No matter how I angle the nozzle, if I leave it on auto the car will get a small fuel shower every time.  Since I fill it up every week or every other week, I know roughly how much it'll take so I blast it full speed until I get close and then slow it down.  I will see the fuel come up to the rim of the filler tube and drop back down several times until it's full.  Very tedious when you fill up as much as I do.  I'm sure it wasn't an issue when these were new, I do believe pumps were way slower than they are now.  However, if there is a way to vent the tube better I'm all for it.

[bull]

I remember having the same problem on my '70 back in the day. It wasn't horrible but it was a pain and there were several times that it puked gas out and down the quarter panel. The size of the vent tube seems suspect to me. The diameter is pretty small for the volume of fuel modern pumps put out IUMO.

[69rtse4spd]

Never had a problem with any of mine.

[A383Wing]

I have always had to monitor the fill rate on the 70 Charger and my old 66 Dart...if left on auto, it would spill over the side of car. I could hear it making noise in the 70 when it's starting to burp. The 66 Dart never took it fast and almost always made a mess.

Never had any fill issues with either of my 66's

Bryan

[johnnyseville]

Funny you should mention this, I have never had this problem with my R/T, but the when I fill the Daytona, keeps taking forever, little by little otherwise it comes back out the filler neck, maybe the restoration they did is the problem.  Will have to look into this.

[tan top]

I remember having the same problem on my '70 back in the day. It wasn't horrible but it was a pain and there were several times that it puked gas out and down the quarter panel. The size of the vent tube seems suspect to me. The diameter is pretty small for the volume of fuel modern pumps put out IUMO.

    yeah think you on to something , vent tube !! never had a problem at the pump , but if put gas in it out of a can with a funnel it backs up , pouring fast  ,  though it would be ok with vent  ,   i have the original vent pipe & the way it goes through the trunk floor  , its easy to slightly kink it when removing it ,  my be cause its small internal diameter even though it looks ok on the out side , it causes some restriction ,  i ran compressed air through mine  60psi , & no way was it  60 psi coming out the other end  , more like 10 ,
been meaning to investigate this for a while   

[model maker]

I always had to bounce the car in order to let the air escape

[Ghoste]

I would suspect the vent first too.

[bull]

I don't remember having that issue on any of my 68s. My Power Wagon is horrible though. Probably takes 45 minutes to fill both tanks.

Troy

Maybe it's just a 69-70 thing. Let's hope so.

[Ghoste]

I had it on my 67 prior to changing out the filler neck.

[model maker]

both my 68 & 69 also.