Since I just had a fuel pump failure on my 98 4x4 Blazer 4 door LS, I was wondering what exactly goes wrong?

Mine just stopped working totally. No noise from it at all even though it was getting power.

I am guessing that there are other reasons such as worn seals or diaphragms and the pump just cannot make proper pressure. But mine just up and stopped moving at all.

 

Cheap pump (these trucks only like Dephi, or delco)
letting the truck get too low on gas, and it over heating

that is 2 that I know of.

 

It's just typical bean counter stupidity and GM's company line in the 90's - "planned obsolescence". The idea of building a product that will fail JUST after it's paid off and / or the warranty is up.

The other problem I see, it seems the engine engineers and the fuel system engineers spoke different languages or were from different planets. Same for the trans guys. And the HVAC guy was either a BDSM freak, or his childhood bully grew up to be a mechanic.

 

What I mean is, what PHYSICALLY happens to them? Some electronic piece shorts out? A bearing seizes?

 

Usually, the brushes wear and the motor on the pump quits. Letting the tank get below 1/4 tank repeatedly shortens the life of the pump as the fuel is also the coolant. You can also run into problems with the fuel sock getting full of garbage. Since you have to pull the pump to replace it, you usually are better off replacing the pump.

 

Or in my case, the fuel sock disintegrates and clogs it up.

 

That's why I only buy black socks. If you have two pair of black socks and your toe goes through one of each, you still have one pair of black socks. Oh wait, we're talking about inside tha fuel tank.

 

My tank disintegrated and clogged my sock and filter lol!!