Executive Summary: Anyone run a fuel filter right before the carb? If so, what did you use?

Long version: Stock Nikki carb 12a, all OEM except basket filters at fuel inlet are long gone. Had horrible flooding issues a year ago, so bad I considered abandoning the car. Finally fixed it with a Holley adjustable pressure regulator dialed down to 2.5 psi. I run the regulator with a pressure gauge, and at the last car show the owner of a RX3 that seemed to know his stuff suggested I remove the pressure gauge as its a potential source of fuel leak and fire. I Removed the gauge and replaced with a plug, but am concerned that there may be flecks of dried high temp thread sealant in the system that could end up in the carb. I really really REALLY dont want to have to rebuild the carb again after the last horror show, so am thinking of adding a fuel filter right before the carb. Anyone done this and what did you use? Do I need to be wary of plastic components sitting right above the engine where it is hot?

Thanks!

 

I have been using the 2nd filter since 2011 without any problems. The transparent filter for about 3 years with very hot summers. I don't see any thermal problems. It is important to replace the old fuel lines with new bioethanol-resistant ones.

 

I had an inline fuel filter on the feed line in one of my 12A cars for a long time. It was glass with a mesh element. I liked it a lot, given the car's unknown previous history and so that I could see what was going into the carb. It was very useful. I don't know the brand, as I didn't install it. I may still have it around somewhere.

 

Thanks folks. Earls in-line filter on the way. Comes in blue to match the car and air box!

Fuel lines were replaced when I was wrestling with the carb issues last year.

 

I always liked to run the glass ones….

To me they look way better than the regular plastic one…..

 

i had one of those glass filters at one point. mine was a Purolator. at any rate, since then i went back and forth between a 2nd Rx-7 filter and a filter for a VW Bug (i think) just before the carb and that was pretty much what i ran and will likely keep running with a carb.

 

Thank you guys for providing this thread and info. I just recently bought an Edelbrock glass inline fuel filter to run in the engine bay. As others have pointed out, I want to be able to see how the fuel looks coming into the carb and also add one more point of filtration. One more question, what is the metal connection on the other fuel line called? When I replaced the rubber hoses, it appears to be some sort of check valve for the fuel - my guess is to avoid flooding of the carb? As a routine maintenance - do you guys recommend replacing it being that it's probably the original one that came with the car.

 

it is a check valve……if you can find it change it…..I theatres mine and it was working ok….

 

I tested mine by blowing through it and it worked as well. My guess is that it's a part better left alone unless it's not working. Plus, I could not find an OEM for sale online.

 

I just installed the Edelbrock inline filter in the engine bay and am very happy with the results. It's pretty cool being able to see the flow of gasoline through the glass see through design. I already planned to change the plugs and fuel filter on the weekend so just added this to the list.

 

"glass fuel filters have caused more fires than ex-wives", from Vice Grip Garage.

 

I had one for years but then realized it was unneeded since I have a good filter before the pump already and I change it regularly. I also change rubber fuel lines every 5 or 6 years as well.

 

Dang, I never thought about them being unsafe. Aside from looking cool, I agree that there's really no need for it if you change the fuel filter regularly; which I do. I will take it off on the weekend and go back to just running the new rubber line I bought.

 

I’ve owned 5 First Gens and always used the glass filter and never had any problems with them…..

 

i had used one of those on my car for many years with no problem. then one day to go for a drive, started it up, smelt gas, shut it off. the rubber seals at the ends finally got dry enough to start leaking. removed it and never put another one back on it.

 

I was thinking failures would be like this car I saw at a meet.
Though it's a plastic filter, it's still resting on the engine. And the battery isn't tied down.

 

Here’s to looking cool for 2 weeks -lol. I removed it as my son rides with me all the time and I don’t see the benefit outweighing the negatives. If anyone is local and wants to pick it up, it’s yours for free (Edelbrock fuel filter 5/8). I can tell you that the things I did notice was that the RPM’s would be jumpy at startup and the throttle response was delayed slightly. My guess is that it’s one more obstacle for the fuel delivery.

 

This is why I removed mine, too many filters on the gas causing retrictions on flows. Stock carbs have very fine filters on the fuel inlets and under the bowl needle seats (nikkis for sure but my Dellorto does as well). Thats a lot of filtration and over engineering. For the everyday users it's probably warranted but for someone that changes filters and hoses on the regular, its over kill and hurts performance to some degree.