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> A couple questions about fuel pumps
Craigers17
post Sep 18 2023, 08:54 AM
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I replaced my fuel filter yesterday trying to get to the bottom of a backfiring issue, which hasn't been an issue since I replaced the carbs about 8 or 9 months ago. In addition, about a month ago, the points actually went bad, and the car started running poorly. I recently replaced the points, and it got the car running well at idle. However, the backfiring issue continued, so yesterday I decided to replace the fuel filter(and I bathed in quite a bit of fuel in the process).

After replacing the filter and remounting the facet fuel pump, I noticed that the fuel pump is very noisy all the time. It used to be easy to hear right at start up, but then faded out under the noise of the engine. Now I can clearly hear it all the time. As a side note, about 3 weeks ago, upon start up I noticed that I could barely hear it.....which was unusual(In other words, the sounds of the pump seem to be going in and out). There is no rubber between the pump and the firewall which is where it is located, so I know that could be an issue. My question is are these varying noises with the fuel pump a sign that it could be failing? Also, I assume that if it was failing, this could cause backfiring issues?

I made sure the carbs were synced again today, and the measure about 6 with the AFM at idle and as I give it throttle, the measurements between sides remains consistent.

My only other question is are points made specifically to match distributors and engine size or distributor only? The points I installed were for 009 and 034 distys, but it says on the package that they are for 12-1600cc engines. They SEEM to be working fine, and I gapped them at .016. According to my digital timing gun, the dwell is spot on at 47 degrees. I know that's a lot of questions, but any help would be appreciated.
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Superhawk996
post Sep 18 2023, 09:09 AM
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Facet pumps are noisy by nature.

When I had one the noise seemed to vary a bit based on ambient temperature and how much fuel I had in the tank which would vary the head pressure the pump inlet sees.

Have you checked your fuel lines under the tank. A kinked line to the pump would change how it sounds and can also lead to some fuel starvation issues when you need higher flow rates.

Like yours, my facet used to be louder at key on until it got a full slug if fuel flowing through it. Could yours have gotten loud all the time because it isn’t getting a good supply of fuel from the tank (kinked line or clogged strainer in tank)?
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Craigers17
post Sep 18 2023, 09:31 AM
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QUOTE(Superhawk996 @ Sep 18 2023, 09:09 AM) *

Facet pumps are noisy by nature.

When I had one the noise seemed to vary a bit based on ambient temperature and how much fuel I had in the tank which would vary the head pressure the pump inlet sees.

Have you checked your fuel lines under the tank. A kinked line to the pump would change how it sounds and can also lead to some fuel starvation issues when you need higher flow rates.

Like yours, my facet used to be louder at key on until it got a full slug if fuel flowing through it. Could yours have gotten loud all the time because it isn’t getting a good supply of fuel from the tank (kinked line or clogged strainer in tank)?


I ended up "accidentally" losing about 5 gallons of gas due to piss poor planning with taking off the filter and replacing the fuel line to the engine compartment. Based on that and how fast the fuel was coming out (mostly all on me and the floor)just due to gravity, I don't think there is any clogging going on. Seriously though, I doubt there is anything going on under the tank. The only thing that really changed was the filter.

Either way, I am seriously contemplating that this might be the time to change over to SS Tangerine lines and new Tangerine pump/filter combo. In that case, I'll be pulling the tank and changing out the sock/strainer and rubber lines under the tank, so that will rule all of that out. Thanks.
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