Original Fuel Pump Filters / Strainers

[bkahler]

While I was looking at options to replace the filter I have mounted at the front carburetor I got to thinking about why it's there in the first place.  So looking at the original fuel system it appears that the fuel pump just had a strainer (no filter) and the real filtering was done at the carburetor.

 

In my freshly installed system I have, starting at the tank a glass bowl with paper filter, electric suction pump, mechanical pump with strainer and finally a glass bowl with paper filter at the carburetor.  The filter at the carburetor is apparently a very porous piece of junk that I need to replace or eliminate.  

 

This got me to thinking as to whether or not I need the filter at the carburetor since I already have a filter at the inlet side of the electric suction pump.  As a temporary measure I'm going to remove the filter at the carburetor and proceed with my engine start up.  The question is with my current setup, do I really need the filter at the carburetor?

 

Did any of the original mechanical pumps have filters or were they all just strainers?

 

 

[ggdad1951]

I have filters in both.

[bkahler]

15 minutes ago, ggdad1951 said:

I have filters in both.

 

That's interesting.  Are they the stone type or paper?  In other words, please provide details of pump and filter!

 

[1949 Wraith]

I was told by some older mechanics to ditch the stone type filters as can they clog and cause issues, even when they look fine.

 

I have an electric primer fuel pump on all my vintage vehicles, so I am running filters before the pumps.

 

I place a pair of dice in the glass fuel filters, they usually get a few comments.

Edited June 1, 2022 by 1949 Wraith

[ggdad1951]

15 hours ago, bkahler said:

 

That's interesting.  Are they the stone type or paper?  In other words, please provide details of pump and filter!

 

mechanical stock pump (original rebuilt) and pleated paper filters from NAPA.

[bkahler]

14 hours ago, 1949 Wraith said:

I was told by some older mechanics to ditch the stone type filters as can they clog and cause issues, even when they look fine.

 

I'm not a big fan of the stone type either.  

 

14 hours ago, 1949 Wraith said:

I have an electric primer fuel pump on all my vintage vehicles, so I am running filters before the pumps.

 

I have the same setup.

 

14 hours ago, 1949 Wraith said:

I place a pair of dice in the glass fuel filters, they usually get a few comments.

 

?

 

 

 

[bkahler]

1 hour ago, ggdad1951 said:

mechanical stock pump (original rebuilt) and pleated paper filters from NAPA.

 

My pump is rebuilt but it's the correct pump (i.e. Carter #).  

 

Do you have a part number for the filter?

 

[JBNeal]

The original setup had the sediment bowl on the mechanical fuel pump then the fuel filter before the carburetor.  If you are filtering before the electric fuel pump, then IMO another filter before the carburetor is belt & suspenders as those carburetors could operate with a certain amount of contamination in the fuel back in the day, contaminants that are now being captured by the electric fuel pump filter element.

[ggdad1951]

NAPA 3943

[bkahler]

On 6/4/2022 at 1:16 AM, JBNeal said:

The original setup had the sediment bowl on the mechanical fuel pump then the fuel filter before the carburetor.  If you are filtering before the electric fuel pump, then IMO another filter before the carburetor is belt & suspenders as those carburetors could operate with a certain amount of contamination in the fuel back in the day, contaminants that are now being captured by the electric fuel pump filter element.

 

I tend to agree for long term operation a pre filter and the strainer are probably enough.  I do however kind of like the idea of more filtration on a new system.  As much as I tried to keep things clean while building the fuel system I'm betting there is still trash of various sizes in the system.  

 

Heck, who would have thought an aluminum fuel filter housing would be porous enough to leak!