Sadly, the lack of information as to WHY the pump is in the tank in the first place is being ignored.......
1. It was decided that the average owner would be indifferent as to the placement of the fuel pump because fuel injection was new and a quantum change in design would be acceptable across the board anyway.
2. It's unwise to put a pump outside of the tank since flow needed to be constant unlike the suck-and-spit mechanical pump run off a cam lobe. The fuel pump was thereby cooled and lubricated, and any leaks that might happen would be self contained (the biggest reason - insurance and insurability, ya know?)
3. Most people drive until the tank is empty. This kills the pump - literally - for lack of cooling and lubrication. These people usually have multiple fuel pump failures and swear they hate any of the new technology.
4. When fuel is placed under a vacuum, eg: sucking it through what really is a long soda straw from the tank - it boils at a much lower thermal value. "Vapor lock" is what it was called prior to FI systems. However, "pushing the fuel" from the pump at the source of the liquid, ensures that the boiling point of fuel is raised significantly. The "vapor lock" syndrome does not typically exist any more. Hooray for technology.
FWIW.... I have 435,650+ miles on my 2000 Astro and never replaced an in tank pump yet. Of course, the rule is to never allow the tank to get below 1/4 full.
I have a 1989 Isuzu Amigo with just over 500,000 miles and guess what? I have never changed the in tank pump there either. The "1/4 full tank at all times" as a minimum rule applies here.
I also have a 1989 K5 with the original in tank pump, and the same rule applies to it - never let the tank get below 1/4 full.
Old Wive's Tale Debunking time: "You will get all sorts of dirt and junk off the bottom of the tank if you run it to empty".........Corrected knowledge: "You ALWAYS draw fuel from the bottom of the tank". The pump inlet does NOT follow the fuel level as it rises or falls. Forget about that old adage.
Another Aesopian-Fable is that you get water and dirt and other junk from gas station tanks. Modern station tanks don't allow contaminants to be delevered to the customer. Period.
Lawsuits and the EPA just keep it from happening anymore. Your state bureau of weights and measures also inspect for EPA failures, volume discrepancies and contaminants in the fuel as metered.
If you live in or regularly fuel up in Pottsylvania, Mexico or distilled your own fuel, then your results may vary.
On FI vehicles, the pump and it's intake is in a little enclosure that keeps fuel surge - from cornering and other G-forces - from starving the pump. Air in a FI system is a problem if one places the fuel suction outside of that small anti-surge container in the tank or it doesn't have one in the first place.
Insurance companies LIKE the pump to be inside the tank, and it's not just to cause you grief. It's there to keep the fuel from squirting all over the undercarriage and immolation the vehicle and the passemgers.
That keeps the negative cash flow down at the insurance companies and leaves the fire department to get kittens out of trees instead of running all over town putting out burning vehicles, and identifying and bagging the crispy critters inside them.
In some juresdictions, if there is an incident with death or property loss, and someone has modified their vehicle to fit some personal, arcane reasoning that made the vehicle unsafe and was at least part of the mitigating reason why death or property loss occurred - then the owner can be held fully liable for all damages. HIS insurance underwriting company will leave him without insurance representation. In other words: without insurance coverage.
An otherwise smart person would realize that moving a fuel pump outside the tank is dangerous, illogical, possibly immoral and it ain't penguin.
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