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New SU Fuel Pump Noise

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J

Jersey

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I just replaced my old fuel pump which glugged a few times when I turned the key and the fell silent. I assume this was the original mechanical pump.

I replaced it with an electric SU pump which sounds like a runaway pacemaker and never stops even when the engine hasn't kicked in ...is this correctly operating?

Any adjustments needed to the rest of the system when I change from mechanical to electric.

Thanks

Jersey
 
Jersey,

What year is your Healey and which electric pump have you installed (model #)?

Since all original SU fuel pumps made for the big Healey had points, the ticking you hear is our indication that the unit is pumping. However, it should pump only as long as necessary to build pressure and then only occasionally after that.

If the ticking continues for an extended period, you have a leak in your system and pressure is not building max shut-off. I would suggest you check for a gas leak forward of the pump (between pump and intake manifold – including carburetors) or an air leak aft (between tank and pump).

Good luck,
Ray (64BJ8P1)
 
I will take the pump off in the morning to see the model number..I purchased it from Moss Motors as the entire part for a 1962 MK II BJ 7 (377-042) which I think is the right replacement.

After a couple of attempts this evening ....no start but plenty of pumping noise...no gas coming thru for some reason...put plenty of gas in the tank.

My thought for the am is to disconnect the outlet see if gas is pumping from the inlet and go from there

Is there some way of priming the pump?

Going to bed.

Thanks

Jersey
 
Jersey,

The pump is self priming.

From your description, it sounds as though you are not getting fuel to the pump. Before removing the pump, disconnect the inlet and check to see if fuel is reaching the pump. If not, remove the pump and blow air through the lines to clear any debris from the tank pickup. No external fuel filter should have been installed between the pump and tank. If so, remove it and reinstal after the pump.

Next, make sure the fuel line to the tank is secure with no air leaks at the connections or from a hole in the line itself. Once completed, reinstall the pump and test. In your test, only allow the pump to run for a short time as the SU will burn out without fuel.

If still not pumping and fuel flow to the unit is good, check the internal filter of the pump. I think you have a square-bodied SU pump and access to the filter is through the removal of the cover plate.

Hope this helps,
Ray (64BJ8P1)
 
Ray has good advice here, especially the blowing out of the line to the fuel pickup in the tank. Perhaps the reason that the new pump is not working is the same reason that the old one died.
 
Ray, good advice...I checked the inlet and there was no gas flow, but should there be?

The location of the new pump is in the same location as the old mechanical pump and I am using the same gas lines....it is located below the rear seat on the passenger side. The fuel line from the gas tank goes from the bottom of the tank and rises up over the rear axle then down to the pump...doesn't look like gravity would do the trick.

Dumb question but should I be getting free flow from the tank or does the pump pull the gas from the tank?

Thanks for the help.

Jersey
 
The pump sucks fuel from the tank. Have you blown air back through the fuel pump inlet pipe into the gas tank? If so does it bubble at the tank? If air does not flow and no bubbles you may have a clogged screen at the pickup in the tank, or gunk in the pipe itself. Questions are how we learn, we remain ignorant when we don't ask them.
 
Jersey--

The fuel pickup goes in the top of the tank and on around the wheel arch so no you are not going to see fuel coming out of the inlet pipe to the fuel pump.

I'd be checking the line between the tank and the fuel pump to make sure it is not obstructed nor leaking as in order for the SU to self-prime it must be pulling against fuel. If that line checks good then and you have fuel in the tank then the pickup itself may be clogged.

Sometimes there is a mesh sock on the end of the fuel pickup and I would suggest removing it and opting for an inline filter that is easily cleaned. Most folks prefer to mount their filters between the pump and the carbs but I have mine between the tank and the pump(s) in order to keep stuff out of the pump filter(s) which have small screen filters that can easily become clogged.
 
When replacing the fuel pump gas drained out of your line to the pump. It will run like that until it gets full of gas again and no air. Some like to put a filter from the tank to the pump, that too should be replaced.
 
Thanks to everyone...blew the lines out...tightened the fittings...and the fuel pump did its thing...less noisy as it had some gas in it and other than a few adjustments for leaks I am off to the races.

Probably need to simply replace a few of the nylon washers to stop the leaks, but I am getting gas and the car is running smoothly.

Thanks to all for hanging in there with my questions.

Jersey
 
It does sound stupid but it does need some mouth to mouth on the fuel intake pipe to get the pump primed. I found that it has to be done each time I remove the fuel pump. A good blow does the trick. Did I look stupid in the hotel parking lot when I replaced the pump? The other Healey guy had a straight face while the wives looked astonished. The next time I had to replace the pump on the side of the road, my wife reminded me to give the BJ8 a BJ. (sorry Reid)
TH
 
The next time I had to replace the pump on the side of the road, my wife reminded me to give the BJ8 a BJ. (sorry Reid)

:savewave:HEY!!!

----You got a funny car.------- :lol:
 
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