Chevrolet 3500 Van very SLOW GAS FILLING

[themexicandoctor]

Never bought this up before but when I go to fill up my tank with Gasoline, on most tanks, its near impossible, to go fast.

I have certain gas stations that I visit where certain.pumps I know its slow but faster than other's.

Is the problem something I am doing, or, the design of the tank due to a Roadtrek Modification?

[avanti]

Slow fuel fill is typically caused by problems with the tank vent system. On modern vehicles, these systems are rather complex, due to emissions requirements.

[booster]

It is a common and very irritating problem with the Chevies, some are worse, some are not too bad.


Being nose down usually helps a lot, and tilted away from the pumps some, so pump selection based on grade is a big deal. Fill handle angle going into the van can also help sometimes, with 3 o'clock being a common one people use. California pumps seem to be by far the worst to get a good fill with.



The problem is the Roadtrek changes to stock that moved the filler to the rear of driver side wheel. The connecting hose they used is rubber, long, and way to horizontal to let air back out, and whatever other vent there is must be very small. If the hose has any kind of dip in it at all, it will fill with gas and kick off the pump.



Ours was pretty bad when we first got it, but it is better since I very carefully straightened out the hose from the filler to tank and added some support (tie wraps). Certainly not perfect, but much better.

[rowiebowie]

Airstream did not move the filler hose on my Avenue. It is about where your lower fridge vent is on un-modified chevies. Mine fills quickly, no problems.

But I had a stock Ford Expedition that had to be filled slowly. When it was still new there was a recall for the problem. Their "fix" did little or nothing to solve the problem, so even factory fill hoses can have the problem.

[themexicandoctor]

Originally Posted by booster

It is a common and very irritating problem with the Chevies, some are worse, some are not too bad.


Being nose down usually helps a lot, and tilted away from the pumps some, so pump selection based on grade is a big deal. Fill handle angle going into the van can also help sometimes, with 3 o'clock being a common one people use. California pumps seem to be by far the worst to get a good fill with.



The problem is the Roadtrek changes to stock that moved the filler to the rear of driver side wheel. The connecting hose they used is rubber, long, and way to horizontal to let air back out, and whatever other vent there is must be very small. If the hose has any kind of dip in it at all, it will fill with gas and kick off the pump.

Ours was pretty bad when we first got it, but it is better since I very carefully straightened out the hose from the filler to tank and added some support (tie wraps). Certainly not perfect, but much better.

Thank you Booster, I am not alone. I think of those Friday pm or Saturday am visits to a Costco* when traveling & my tanks were low - pissed off other shoppers & attendants, who think that I must have a 500 gallon tank.

COSTCO IS THE WORST.

This is not an exaggeration; it can take 20 minutes to fill up a tank without topping it off whereas some pumps are only 3 minutes.

[themexicandoctor]

When filling there is not a small enough flow setting to lock the handle & if you ever do find one,, just a slight bump or angle & you have to start again.

[themexicandoctor]

Booster,

Is the fix a requirement of someone qualified as a Mechanic or could I do it myself?

Either way, if you have some instructions could you please post them here, we cannot be the only two on the planet.

[booster]

Originally Posted by themexicandoctor

Booster,

Is the fix a requirement of someone qualified as a Mechanic or could I do it myself?

Either way, if you have some instructions could you please post them here, we cannot be the only two on the planet.

Lots have tried to fix theirs themselves with varying success, from what I have seen.


You would need to be able to get the left rear wheel off and the van SAFELY supported as you will have your arms and maybe head in the wheelwell and be tugging and pushing on stuff.


At the top of the frame there should be a rubber hose, about 1.5" diameter in a corrugated sleeving running along next to the brake cable and other things. Look for any low spots or high spots along that hose and use plastic tie wraps to support it straight.


The hardest part for most people is having the lifting and supporting things, as you can't use ramps to do it.

[GroupB]

Here are views of the hose in question.

[themexicandoctor]

This i can do.

At a friend's shop.

THANK YOU!

[themexicandoctor]

Group B,

You had the same issue?

[mkguitar]

You are likely dealing with the vapor recovery system which is common in CA and less so elsewhere- it'll "kickback" and turn off



My chev van fills about same rate as my other vehicles


it always seemed worse at ARCO and I avoid them


Mike

[themexicandoctor]

USA Gas is usually best for me or UNITED OIL*, great prices too.

Newer, big brand gas stations are usually the slowest.

[avanti]

Originally Posted by themexicandoctor

Newer, big brand gas stations are usually the slowest.

This is probably because their pumps have the best evaporative recovery systems, as per mkguitar. This is a Good Thing, but they are dependent on properly-operating tank venting in the vehicle. I know nothing about the Chevy system in particular, but it should be understood that in modern vehicles these systems are not just tubes out to the air. They are complex, active ECU-controlled systems that include solenoid valves, carbon canisters, flow sensors, pressure sensors, and so on.

I do not doubt that this particular vehicle has systemic problems, as reported by those who know it in particular. My point is that even with a properly-designed vehicle, there is a lot that can go wrong, and any fault is likely to make modern, clean pumps misbehave.

[booster]

Originally Posted by avanti

This is probably because their pumps have the best evaporative recovery systems, as per mkguitar. This is a Good Thing, but they are dependent on properly-operating tank venting in the vehicle. I know nothing about the Chevy system in particular, but it should be understood that in modern vehicles these systems are not just tubes out to the air. They are complex, active ECU-controlled systems that include solenoid valves, carbon canisters, flow sensors, pressure sensors, and so on.

I do not doubt that this particular vehicle has systemic problems, as reported by those who know it in particular. My point is that even with a properly-designed vehicle, there is a lot that can go wrong, and any fault is likely to make modern, clean pumps misbehave.

I think the vapor recovery at the pumps is not a passive setup, but has a source of low vacuum to actually pull the fumes out and to a recovery setup to condense out the gas fumes. I think in the big scheme of things, nearly all cars probably don't have big enough hoses from the tank to the vapor cannister, and even if they did I don't know if the cannisters could handle the near saturated fumes out of a 30 gallon, or more, tank.



If the above is correct, you will always have at least some air coming out the filler neck when you fill the tank, and many times I can smell it here where we don't have vapor recovery pumps. Under those circumstances, a situation that blocks the air from coming up the fill tube, will certainly cause the pump to shut off or it would run over very quickly.


The Chevy system itself likely doesn't have any issues of consequence as we don't hear of these issues on the non Roadtrek Chevy models, and tradesman would never put up with super slow fills in their work vans, as time is money.

[Doneworking]

Our Roadtrek 210P has had this slow to fill/shut off the pump problem since the day we bought it. I keep a piece of 1/4 inch drip irrigation tubing about 10 inches long inside the fill compartment. I insert that little tube into the RT gas line prior to inserting the station pump nozzle into the RT. That seems to help me a lot in getting a decent flow and as others have stated it varies from station to station as to how severe the problem.

I have never had our RT in CA, but I have filled a lot of rental cars over the years in CA and IMO filling anything in CA is a real pain. I certainly understand the environmental issues of why it is that way.

As others have stated, it seems to vary from rig to rig as to severity but is a well known gottcha in RTs. My 1/4 inch tube solution very well might not be of benefit on others RTs because the way they put in the gas fill line does, I am sure, vary from rig to rig. It works for me.

[GroupB]

Originally Posted by themexicandoctor

Group B,

You had the same issue?

Yes. Approaching the gas pump so the vehicle nose is down, as pointed out, is most important. Some stations, like Costco, have one way traffic so you can't choose your direction of approach. Sometimes there is a slight dip where the concrete pad meets asphalt. Getting the front wheels in that spot can make the difference between frustration and a normal fill. When the nozzle keeps shutting off, I turn it to the (about) 3 o'clock position and hold the nozzle while filling. Another trick is to insert the nozzle into the fill tube, then pull it back about an inch and try filling while holding the nozzle at that position. Some people have a leveling block handy and use it for the left rear wheel if needed.

The problem was mild in my case, and when I was doing work in that area with the wheel off, I adjusted the hose position with tie wraps. The movements were minor but helped. It's rare now to have the problem.

[mkguitar]

Originally Posted by Doneworking

I certainly understand the environmental issues of why it is that way.

The "cheat" is to hold the collar back with your other hand- which is often required on motorcycles ( or gas cans)


if uncaptured the hydrocarbon vapor released from a gas fill can easily equal a few hundred miles of operation in any car made last 15 years


Mike

[themexicandoctor]

I have a Scooter & a Z1000, tried all of those techniques, what works at one location might not work at another.

Its been 9 years, I feel like I have come out of rhe closet & there are other people just like me ...

What did you mean by this Mike?

if uncaptured the hydrocarbon vapor released from a gas fill can easily equal a few hundred miles of operation in any car made last 15 years

[themexicandoctor]

I also Iive in LA so any thing California does, LA tries to do better.