Is an external fuel pump necessary?

[GrahamHO]

Originally Posted by Canibul

I commonly use the 'blow into the tank' vs. suck on the hose method when siphoning fuel. Made me wonder about the idea of applying positive air pressure to the vent line in a conventional tank. Seems a little air pump up top would solve a lot of issues. Also would help find any leaks in the system.

Early yet, still on first cup of coffee and watching a sunrise.

I used to use the "blow into the vent" with my mouth method to get fuel flowing after changing filters. I had to run around quickly from the vent line under the tiller to the engine to close off the bleed screw. My filler cap has an O ring seal. It worked best with a full tank but not so well otherwise.
My neighbour on the marina saw me doing this and asked why I don't fit a B.... squeeze bulb as he had. So I did.

Old speedway cars used to have an air pump beside the driver that they pressurised the fuel tank with. TQ midgets used motorcycle engines which had no fuel pumps because they gravity fed on the donor bikes, and there were no batteries for electric pumps on speedway cars.

[Nicholson58]

Originally Posted by GrahamHO

Squeeze bulbs are not dodgy, but rather they are optional and useful. You don't need to carry a spare bulb only a length of spare fuel line and some clips, which I routinely have on board in case any fuel line needs replacing unexpectedly.

I can't understand how polishing the fuel to make it "super clean" can "stretch out lube oil changes to 100,000 miles". Diesel fuel is either clean or not clean and is a separate system to the lubricating oil.

If trucks do big milages between oil changes it is mainly because they are always running and never get cold, and also they have efficient lube oil filters, which might be changed before the oil is changed.

You apparently missed the part of my post where I noted we installed the fuel polisher AND similar filters on the engine and generator. (total three filter systems)

An excellent article on fuel polishing for marine diesels.
Captn Wil's Fuel Polishing System: Trawlers & Trawlering How To

class 8 over the road trucks: over 1,000,000 miles each.
https://www.puradyn.com/letter-from-the-presidentcoo/

By-Pass Oil Filtration


Two sources for bypass type filters and more discussion on the use & installation.
Gulf Coast Filters, Inc. Specializing in Bypass Oil filters, Fuel filters, Hydraulic filters and Custom filtering

Frantz Filters, LLC. Official Website

[GrahamHO]

Originally Posted by Nicholson58

You apparently missed the part of my post where I noted we installed the fuel polisher AND similar filters on the engine and generator. (total three filter systems)

I didn't miss anything. You wrote "The fuel polisher AND similar filters on the engine and generators" says nothing about oil filters. You understood what you meant but you didn't mention oil filters, only fuel polishing.

It's like hanging up a sign saying "back in ten minutes". You understand the message but nobody else does.

It now appears from what you have just written that you are also talking about bypass oil filtration in addition to fuel polishing.

Bypass engine oil filtration kits were being promoted in the 1950s in magazines such as Popular Mechanics. You could buy a bypass oil filtration system to screw onto your Ford V8 flathead. One such used a toilet roll as an element. Independant tests conducted at the time suggested no benefits from bypass oil filtration and they actually created a vulnerable location for a possible oil leak that could lead to loss of lubrication.

There are other contaminants in older lubricating oil that all the filtration in the world can't remove.