27 gallon gas tank install on 16 SC

[Fisherdv]

Maybe grease on a razor blade would keep the shavings on the blade. It worked well with the drill bit. The one thing that makes me think this is the problem now is the fuel spilling out the filler even with an empty tank. The fuel must be hitting that thick lip and backing up

[Yachter Yat]

   Yeah, you may be right.  Guess there's only one way to find out for sure.  Keep in mind, I don't think you'd ever be able to "full throttle" a fuel nozzle in these tanks.  I know I could never do it.  That said, cutting that neck may at least speed the fueling-up process to a point where it's tolerable.

Yat

[Fisherdv]

Yes, I'm not looking for full throttle, as you said tolerable

[Rokefin]

FDV  that is a very thick filler neck and hopefully that could be the problem, I mentioned on page 4 that it might be a good idea to chamfer the ID of that filler opening....nothing to lose at this point. Next step would be to put a mast and sheet on top and turn her into a sail boat

Were all very hopeful for a solution as this headache has grown into a big nightmare.

[croaker stroker]

Good idea Yat... :bowdown:....   Chamfer the neck.

Stuff something like a rag or hunk of foam in the hole tied to a length of Spectra leash.

[AJFishin]

It sounds like you're leaning towards widening the ID. I'll have some time tonight and I'll try and pull the hose off and get a measurement.

[croaker stroker]

I wonder if they increased the thickness of the new tanks to make them less permeable?

[Yachter Yat]

   Croaker, that's a damned good question.  Judging by the pictures AJ and Fisher posted, you'd swear that might be the case.  Sounds like this could qualify as a "Dear Arima" inquiry.  Also, seems to me, anybody replacing a fuel tank might want to know this. 

Yat

[Fisherdv]

It sounds like you're leaning towards widening the ID. I'll have some time tonight and I'll try and pull the hose off and get a measurement.

AJ, it's ok, no need to measure. It's kind of a pain to take that hose off. I think the pics clearly show that mine is smaller. I'm not going to try to widen the whole neck, just maybe try to take some of the square edge off

[Fisherdv]

I wonder if they increased the thickness of the new tanks to make them less permeable?

The main body of the tank is not very thick, only the vent and filler. There are regulations regarding the minimum hole diameter (7/16) for the vent and I don't remember what it is for the filler. I think these tank manufacturers are lacking a bit of quality control here. I mean, it's a gas tank, you should be able to put gas IN it :hoboy:

[Fisherdv]

I'm going to try putting a smaller diameter hose inside the 1 1/2 in ID filler hose as the fellow wrote in the post I copied on page 9, #223. I found a fuel hose that is 1 1/2 OD that should fit perfectly in the filler hose so that would eliminate any hang ups on the filler neck from the tank. Essentially making it a straight shot, the same diameter, the whole way into the tank. Hopefully that will at least test the theory of the filler neck thickness restricting the flow. One way or the other I'm going to get this figured out. (Hopefully)

[AJFishin]

Another option, if your hose option doesn't quite work to well, is to maybe use something similar to this:

[Fisherdv]

Another option, if your hose option doesn't quite work to well, is to maybe use something similar to this:

I was just looking at those today! Lol. Where did you see that one? I like that it's metal. I just may have to "force feed" this tank 

[croaker stroker]

My new truck came with this...

[Fisherdv]

I can imagine the look on the Chevron attendants face when he sees me snap on my rubber gloves, and pull out that funnel. I could tell him I'm giving my boat a prostate exam 😷 He's  probably got the EPA on speed dial! 🤪

[AJFishin]

They're called Justrite funnels. You can get them on Amazon or WalMart $20

[Fisherdv]

I put a little bit of a bevel on the inside top edge of the filler neck to take a bit of the square edge lip off. Was very easy to do with a sharp razor and a sock stuffed in the hole to prevent shavings dropping in. It was almost like cutting candle wax it shaved so easy. Guess what, no bueno! Gas still coming back out the filler and now the vent every time as well. How with a half empty tank and all that air space does the fuel rise up and come out the vent??? Is pressure building up? If so why.? Is vent hole still not large enough? I opened it up to 3/8 but regulations specs say 9/16 or 7/16 MINIMUM. In that case my vent is still a 1/16 to 1/8 in too small. I even unhitched from the truck and raised the trailer jack all the way up. Why is the gas not staying down? A simple 3-5 minute fill up is taking me 20-25 minutes by the time I fill the tank and clean up all the spilled gas mess. I mean, I cannot even pump gas with any kind of steady flow, it's stop and go or a trickle at a time 

[Yachter Yat]

   Wow!  I'm stumped!  Maybe it is the vent???  Gonna have to sleep on this one, Fisher. 

Yat

[croaker stroker]

Doesn't make sense. 

[Fisherdv]

3WT, you were right, beveling the filler didn't seem to help. I have to try all options at this point.

[Yachter Yat]

   Okay, here's another "shot-in-the-dark":  Do you suppose there could be some kind of "burr" in that tank?  What I mean is, some piece of plastic inside the tank, (maybe a glitch from the molding process) sticking out inside the tank just enough to catch, and thereby, upset the fuel flow?  If nothing else, I suppose looking down into the filler neck and checking could put this one to bed.  Like I said.....a "shot-in-the-dark". 

Yat

[Fisherdv]

I looked down the filler neck, no burrs that I could see. I really can't understand why fuel is coming out the vent also. With a half tank of gas there is about 10 inches or so of air. So how does the fuel rise up through all that air space and find its way all the way up the and out the vent hose? Pressure build up??? Vent hole at the tank still not large enough? I don't see how if it was splashing it could get all the way up a curved, small diameter hose with enough force to come out the p-trap vent

[Threeweight]

Gas will foam and aerate when you pump it.  My guess is you are pumping from a pretty high speed pump, with a decent drop from the nozzle to the fuel level in the tank.  It's causing it to foam and aerate, and the aerated gas is foaming up and out the fill and vent.

Only solution is to slow down the pump.

[Fisherdv]

 I've tried a few different gas stations and same result. I know I'm not going to be able to fill full throttle but I can't even squeeze the nozzle at the lowest, constant flow level without the spill over. So basically I have to squeeze light as possible, stop completely, sqeeze as light as possible, stop and so on. There is no way I can fill with the nozzle flowing constantly even at the lowest flow setting

[AJFishin]

Have you tried putting gas in with a gas can and seeing what happens?

I'm curious if that flow would work better

I know my 5 gallon gas can with the fancy safely nozzle, pours gas in slower and takes a breather every 5 or 10 seconds as it's pouring in.

If that works, one of these might be in your future.