Gas station pump speed, filter type, filter age?

[Digital2k2]

A while ago I looked up fuel filters for gas pumps. I noticed that there are different micron ratings... I'm not sure if they have a pre-filter then a more efficient filter after that, or if there are just different options?

There are 3 different shell stations I will sometimes fill up at around here and all of them have a very slow pump speed with the handle squeezed open. It is the equivalent to about 1/4th open on the bp and 1/2 open at farm fresh station by them.

Could the shell stations just use a more efficient filter that inhibits flow? Or is it more likely that they don't change their filters as often and they are clogged?

Once at the shell station in town that see's the most volume, a pump was so slow that it took me about 4x longer than normal to fill. It was obvious that the filter was way too old and clogged up with junk on that pump.

I wonder if contaminants manage to get by an old filter or if it only slows the flow way down when it gets clogged? Actually the bp station down the road pumps so fast I wonder if he has any filters in there at all... Anyone hear of stations skipping on the filters?

 

[Eddie]

My local Texico station uses 5.0u fuel filters. I've watched them change them. I ask how often and they are changes by some fixed number of gallons thru-put. I have a feeling that top tier/major brands change regularly but, off brands may not. Ed

 

[Hokiefyd]

One comment about slow gas pumps.

If you have a pump that seems to be pumping very slow, the station may have a leak in the line. On top of each underground storage tank is a line leak detector. Most today are electronic, but some are still mechanical. Either way, if the system detects a leak in the product line to the dispenser, it will restrict flow to about 1/10th of normal. This prompts the customer to complain to the store clerk, which puts a fire under them to do something about it.

If you're getting 25% or 50% flow, it's probably a separate issue. But worth noting anyway...check with the station clerk; they may know of an issue.

 

[JHZR2]

Some convenience stores around here apparently flow slowly so folks will go in and buy coffee. This is the claim from the operator, who changed out the filters many times tring to speed up flow.

 

[FMC]

Originally Posted By: Hokiefyd

If you have a pump that seems to be pumping very slow, the station may have a leak in the line. On top of each underground storage tank is a line leak detector. Most today are electronic, but some are still mechanical. Either way, if the system detects a leak in the product line to the dispenser, it will restrict flow to about 1/10th of normal.


This is spot on, the filters used have 2, 10, 30 micron filtering ratings, 25gpm max flow rate. They should be replaced every 3 months.

http://www.cim-tek.com/

 

[Digital2k2]

Didn't know that about the leak detectors, that's interesting. I'm sure that fill up wasn't near as bad as when I pumped gas from a station while it was getting its tanks filled. My gas gauge took 10 miles to read full, which made me think that sediment stirred up from the storage tank got pumped in (only time it's ever done that).

That might be the site I saw the different micron ratings on. I wonder if they're required to run all three or if they can choose to just run the 30 micron filter. I almost wouldn't be surprised if some stations bypass the filter somehow to save on having to replace them.

 

[surfstar]

Say what you want about CARB regulations, but one includes that nozzles must flow between 6-10 gal/min - any more or less is out of spec and must be fixed. Stations are tested a minimum of once per year also.

I highly doubt slow flow has anything to do with filter clogging. With all of the expensive equipment at a gas station, delaying filter changing to save money makes no sense; those are likely the cheapest maintenance item.