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Best and safest fuel filter to use?

1967 satellite

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What is the safest and best fuel filter to use on a big block. Had a steel one (cheap one) leak a few years ago but fortunately did not start a fire. Don't want or need to worry again.
 
If you’re looking for stock I would use a Wix. Metal.
 
I use 2. One between the tank and pump and one between the pump and carb. Metal and away from heat or shield it.
 
20210315_204512-1.jpg
here's a nifty little strainer I use In my carbs.
It goes right behind the hard Line fuel fitting at the carburetor.
 
WIX - they are the only fuel filters I trust. You can also find them under NAPA's house brand. You'll want a 100-micron fuel filter before the fuel pump, and a 10-micron fuel filter after the pump. If you're experiencing 'vapor lock' or fuel percolation issues, it's a good time to install a WIX filter with a fuel vapor return line [Part # Wix 33041]. You can run this to your fuel filler neck, it doesn't need to be plumbed into the OEM tank.
 
WIX - they are the only fuel filters I trust. You can also find them under NAPA's house brand. You'll want a 100-micron fuel filter before the fuel pump, and a 10-micron fuel filter after the pump. If you're experiencing 'vapor lock' or fuel percolation issues, it's a good time to install a WIX filter with a fuel vapor return line [Part # Wix 33041]. You can run this to your fuel filler neck, it doesn't need to be plumbed into the OEM tank.

Do you mean Wix 33040?
 
I use 2. One between the tank and pump and one between the pump and carb. Metal and away from heat or shield it.

The only problem with putting a filter on the suction side of the pump is: it ADDS to the suction pressure loss of the pump and system. Adding to the suction pressure loss reduces the overall pump capacity, both in terms of VOLUME and PRESSURE capabilities. IF using 2 filters were such a good idea, why didn't the manufacturers do do? BTW....filters are rated on their micron rating (particle size to be trapped). Defination of a micron: "micron" is an abbreviated term for "micrometer", or a millionth of a meter (1/1,000,000 meters). This is about . 00004 inches. For Size comparison, a human red blood cell is about 5 microns across. This small size will pass thru the carb or EFI without consequence. Just my opinion of course.
BOB RENTON
 
Holley recommends a filter before it's electric pump.
 
Holley recommends a filter before it's electric pump.
But what type of pump?? Positive displacement piston pump or rotary vane type, which is the general type used in submersible in-tank pumps. I'm curious as to the reason suggested.....other than to sell more stuff....
BOB RENTON
 
Holley recommends a filter before it's electric pump.

These are pre-filters before the pump, usually 100 micron. The post pump filters are usually less than 30 micron.
The filter material rated in micron is like RJRENTON described. Most filters don't tell you the filter area. You need a minimum amount of area to prevent loss of pressure, and as the filter starts trapping junk, the flow area is reduced. So the size (Area) of the filter material will make a difference on how often the filter need to be cleaned or replaced.
 

Thanks for the link.....vane pumps typically like a "flooded suction" or having the inlet lower (or equal to) the supply side outlet. This reduces the NPSHr (Net Positive Suction Head required) so it will NOT subtract from the outlet pressure produced. Vane pumps are more sensitive to abrasive wear because of their construction.
BOB RENTON
 
View attachment 1084403here's a nifty little strainer I use In my carbs.
It goes right behind the hard Line fuel fitting at the carburetor.

I just installed my two carb strainers this past weekend. My question is are they suppose to float inside the chamber or are they supposed to fit into the brass fitting? My old ones fit into the backside of my brass fittings, the new ones didn't fit into the fitting. How did yours fit?
 
I just installed my two carb strainers this past weekend. My question is are they suppose to float inside the chamber or are they supposed to fit into the brass fitting? My old ones fit into the backside of my brass fittings, the new ones didn't fit into the fitting. How did yours fit?

I recall mine was a snug fit in the brass fitting. But I can confirm this after work today and post a picture. If you need to see if there's anything different?
 
10 microns is still pretty small at .0004" so yes, make sure that filter has plenty of surface area.....
 
What is the safest and best fuel filter to use on a big block. Had a steel one (cheap one) leak a few years ago but fortunately did not start a fire. Don't want or need to worry again.
Uh, electric pump, or mechanical? Stock, up by the engine, or back by a rear mount electric pump.
More info=better advice.
 
I just installed my two carb strainers this past weekend. My question is are they suppose to float inside the chamber or are they supposed to fit into the brass fitting? My old ones fit into the backside of my brass fittings, the new ones didn't fit into the fitting. How did yours fit?
I just installed my two carb strainers this past weekend. My question is are they suppose to float inside the chamber or are they supposed to fit into the brass fitting? My old ones fit into the backside of my brass fittings, the new ones didn't fit into the fitting. How did yours fit?
20210706_191417.jpg
the brass one on the right was in a holley carburetor from a 413 motor home. and the left one was in a carter avs. 4426s and both screens fit snug in the fitting.
 
IMO....GM's idea was to have a pleated paper filter cartridge inside the carb, behind the inlet fitting and it was spring loaded to keep the filter against the back side of the inlet fitting. The only thing worse was the sintered bronze element used early on. The theory was IF the element became restricted, due to dirt/crud, the inlet pressure would over come the spring tension, pushing the cartridge back, allowing fuel to flow around the element. Did it actually work as intended? Unknown....The surface area was small, so what most owners did was to remove it completely and add an external filter. BTW....re the filter screens shown, personally, I always remove them as they offer little in filtering out micron size particles, and offer a good chance to cross thread the carb threads after several remove/install cycles.....BUT, this is just my opinion.
BOB RENTON
 
The only problem with putting a filter on the suction side of the pump is: it ADDS to the suction pressure loss of the pump and system. Adding to the suction pressure loss reduces the overall pump capacity, both in terms of VOLUME and PRESSURE capabilities. IF using 2 filters were such a good idea, why didn't the manufacturers do do? BTW....filters are rated on their micron rating (particle size to be trapped). Defination of a micron: "micron" is an abbreviated term for "micrometer", or a millionth of a meter (1/1,000,000 meters). This is about . 00004 inches. For Size comparison, a human red blood cell is about 5 microns across. This small size will pass thru the carb or EFI without consequence. Just my opinion of course.
BOB RENTON


I agree and thats why the factory just used the sock on the sending unit tube before the pump. I see alot of guys run the big Fram cartrige type fuel filters before the electric pump and I was told thats not a good idea just because of what RJENTON posted here. That type filter should be after the pump. I was even told the best is to run a larger size line on the suction side of the pump for best results. Ron
 
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