Y block fuel pump

Sid

Sid

Well-known member
Has anyone ever had a mech. fuel pump that has pressure on the carb. side but will not suck fuel on the inlet? This is an Airtek 4206 pump and I do know there are no inlet air leaks.
 
The guy was driving about 35 and car quit. I went to where he was and checked for spark all was good. Pulled fuel line off carb. and cranked engine for about 15 sec. and no fuel. Hooked hose to the fuel line going to tank and gave a little suck and got fuel. Bench tested pump and felt pressure on carb. side but feed side would not suck fuel from a can. Found another pump in my stash and car is running now. BTW that is an expensive pump buying new. Especially the Carter M73066. Airtek is about $100.00 Carter $180.00
 
Sid said:
Has anyone ever had a mech. fuel pump that has pressure on the carb. side but will not suck fuel on the inlet? This is an Airtek 4206 pump and I do know there are no inlet air leaks.
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39deluxecp said:
must be a stuck or inoperative check valve in the pump.
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There is a small check valve on both the inlet and outlet sides of the fuel pump.
If just one is stuck or not seating, the pump sort-of works but not like it should.
Much like the intake & exhaust valves in the engine.
.
 
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Those new pumps you get that now cost $109.00 are junk. Made in china! they have really good pump diaphragm material. Problem with them is those two check valves in the bottom chamber go haywire. You can pump all you want, and it will just drain out into the supply line from the other valve.
Sometimes the pump will still supply enough fuel to the carb to keep it running while unbeknownst to the owner, the check valve is draining some of the gas as it is pumping, until finally, that valve gives out altogether.
 
I have been running FE ( 390 ) fuel pumps on my Y blocks, they are easier to find in the local parts store
 
I agree Jim. Thing is though this car belongs to a lady and this car was her fathers car. She is a real stickler for original plus it has the vacuum wipers. I bought a new Carter and went to install Thursday and it don't work. Even tried on the bench and nothing. Sending it back Monday.
 
Yeah Sid, I know what you mean needing to keep it original and the Vac. wiper situation. I use the factory style double action pump on my '51 Merc. It is all stock except for the headers and dual exh. the double action pump is a must if driven in the rain.
 
I am running my second new Airtek in my '55 now. I expect it will last a few years before trouble starts again. I have one of those clear plastic inline fuel filters ahead of the carb so it is easy to tell if the pump is gurgling and draining.
The filter is Duralast #FF5-16DL for 5/16" fuel line (that's the original fuel line size).
If worse comes to worse, you can always tell the lady that you can install an Airtek, but don't allow the engine to set idle for long periods of time where ethanol sediments build up in the bottom and clog those check valves. Maybe use a premium gas additive. I have been using Lucas Deep Clean injector cleaner, but they also have a product called Lucas upper cylinder lubricant in a smaller bottle and less expensive. Either one is alleged to have the same effect (clean & lube carburators, fuel injectors and valve seats.
 
Okay...I put a used pump on the car for the people and it ran great. I get a call about 8 days later that the car wont start. In the meantime I got a new Carter pump. So I go to the peoples house and crank the car for 10 -15 seconds and nothing. Had spark too. So I gave it a shot of fuel in carb. and she started and ran great. I took the car home with me again and installed new pump and it don't work. So I pulled it off and bench tried it and still no work. Put the other pump on and it works. This is where it gets strange now...I let the car set for 3 days and went out to start it pumped gas a few times and pulled choke almost started but did not. So I pull the line off the carb. and crank for about 15 sec. and no pump gas. So I crank with my finger kinda over the outlet line and feel a slight pump suck action on the outlet. Then suddenly it starts pumping gas. Hook up line give a shot of gas in carb. and all is well. Shut car off for a few hours and pull off line to carb. and again no pump gas. But if there is gas in the carb. the pump will start pumping and all is good. So next to eliminate a pinhole in the line I set a container under the car with a line in it to eliminate the tank and line from the tank and still the same problem.So I get my fuel pump tester and crank engine for about 15 seconds and the gauge goes to about 7 lbs pressure then back to about almost 2 lbs suction. This is from the line to the carb. The needle goes back and forth with every stroke. Seems to me the pump should go to 4 or 5 and stay there until released. Although 5 is really pushing the envelope on a ECG carb. Although nany of these replacement pumps are advertised at 5.25 max. Should be more like 3.25 max.
 
Typically, I would say that you should never be able to read suction on the fuel pump output line. So, sounds to me that there is a problem with the pump. I doubt the rubber diaphragm is at fault, those rubber diaphragms in the Airtex pumps will withstand an A-bomb explosion. It would almost have to be one of those check valves in the bottom of the inlet chamber.
There's another problem though, and that is her Holley 2110 (ECG) carb is leaking gas out of the float chamber dry after a couple days. If there was enough gas in the carb to start and run the engine for a few seconds, even a partially faulty fuel pump might be able to pump enough gas up to the carb to keep the engine running.
I am not saying you should fix the carb and forget about the faulty pump. The output pressure of a good new Airtex pump might be a little higher than OEM specifications, but it should not be enough to negate the carb float, which would flood the carb immediately. I am running a Ford EBU carb on a 292 Y-block with an Airtex pump and there has never been a problem.
Things to check on the carb: busted power valve (economizer) diaghragm will leak all the gas out of float chamber. Also test to see if the accelerator pump ball check valve is not seating properly in it's hole at the bottom of accelerator pump chamber.
The Holley 2110 ECG (1956) works exactly same as the Ford EBU (1954/55) and Holley 2100 (1955), except the 2110 has bigger throat and larger venturies than the previous years.
 
I picked up another new fuel pump from a local auto parts yesterday and now all seems well. I think the used one I had on the car had a bad check valve.
 
I bought an Airtek pump a few years ago from O'Reilley's for the '67 Galaxie I had at the time. It worked for one day then quit. Exchanged for another one and it worked for one week. The parts man even admitted that there have been a lot of bad mechanical fuel pumps that have went thru their store lately. I got an electric and there were no problems after that.
 
I just got a Carter9350 from Hill's now to install it this week. My old carb has a stop check valve no vacuum on on side. $196.05 including shipping.
 
Faulty Airtek pumps seems to be a widespread problem, dare I say a pandemic (airtek19)??

Apparently Airtek has acquired Carter and may be having a transition issue.

Many posters in my 'other' forum have installed an electric pump between the tank and mechanical pump. It gets around crappy pumps and vapour lock.

One guy has wired it to the cigarette lighter and only uses it to start the engine, then runs on the mechanical pump. The electric is the backup.
 
I thought there was someone here on Ford Forum that rebuilt fuel pumps with modern fuel compatible parts and could set pressure to Ford specs?
 
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