Author Topic: Long Paper Carburetor Fuel Filter with Check Valve  (Read 504 times)

Offline rhinosoft007

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Long Paper Carburetor Fuel Filter with Check Valve
« on: January 01, 2019, 01:19:22 PM »
 :)
Wow - check the subject line. I have been working on my carb for a while now - never happy with it's idle, seemed to be running out of fuel all the time and hunting.

I replaced the old fuel filter, it looked new but what the heck, there was this funky rubber plug and spring inside the filter inlet. Some research indicated that this is to prevent fuel drain back from the carb - I could barely blow any air into into the filter with it installed..fuel?

Just a lesson learnt - put in Cliff's new filter and big improvement.

Graeme

Offline Cliff Ruggles

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Re: Long Paper Carburetor Fuel Filter with Check Valve
« Reply #1 on: January 02, 2019, 02:34:45 AM »
The factory also went to solid (not windowed) inlet seats to prevent drain-back.  Those fuel filters are very restrictive and not recommended. 

If you want to prevent any and all drain back issues, leave the "clip" off the needle.  It's only there to lift the needle off the seat when the carb dries up, to keep it from sticking.  I don't see that with this new fuel as it pretty much evaporates to nothing leaving little if any residue anyplace.

My carb has been in service w/o a clip on the needle for decades with zero issues, and my car sits for long periods of time as well.......Cliff

Offline Kenth

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Re: Long Paper Carburetor Fuel Filter with Check Valve
« Reply #2 on: June 16, 2019, 12:49:47 PM »
The float pull clip, fastened to the float valve, hooks over the edge of the float arm at the center. Its purpose is to assist in lifting the float valve off its seat whenever fuel level in the float bowl is low.
CAUTION: Do NOT place pull clip through small holes in top of float arm. Severe flooding will result.

Fuel filter check valve is an "anti-rollover" safety device keeping the fuel from leaving the fuel tank through the carb at an accident.

The non-windowed inlet valve were introduced so that all fuel will be discharged over the top of the float valve seat. This provides a smoother flow of fuel through the float valve seat to control fuel turbulence in the float bowl.

And, if an original fuel pump is used, it has an anti-drainback valve built into it keeping the fuel in the float bowl before it evaporates.


Offline rhinosoft007

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Re: Long Paper Carburetor Fuel Filter with Check Valve
« Reply #3 on: June 17, 2019, 12:51:28 AM »
Thanks for the reply guys - good information.

Graeme