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Fuel Pump Leaking

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Naomi

Jedi Hopeful
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Smelled and noticed some gas on the cement this morning and discovered the fuel pump on my 79 is leaking. Didn't determine that until the hubby replaced the fuel lines from the tank to the pump and from the pump to the metal line. Any fix for a fuel pump that is leaking at the threads?

Next question -- since the hubby has to pull that one all the way out wouldn't it be nice to have an alternate electric pump under there in case this old type tears up and then all I would have to do is flip a switch. I've heard of others doing it but can't remember the name of the replacement pump. What is it and where can one buy one?

Your turn /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
 
"Facet" and can be had at most NAPA stores. Be sure to specify the low pressure version. If the old one is leaking at the threaded part, it may be a simple matter of replacing the copper washers. Unless it has those poxy plastic couplings, that is. Do ya know which it is? Banjo fittings of metal or straight fittings of brass or plastic?
 
Are you talking about the threads of the banjo fittings? If so then I agree, replace the washers and all should be well. I don't remember if the washers on the MGA pump are copper or fiber.
 
NA!!

If its leaking at the hose connections, its just that he either left the washers out or they're worn out...check them before doing anything else. You should be able to get either fiber or copper washers locally by just taking the old one in to the parts house.

Do you need a Facet electric backup pump? IMHO, NO! If you've built yours properly, there's no reason to think it'll go out. If he has to remove it to fix a leak other than at the hose connections, rebuild it & forget about it.

Think of it this way: that fuel pump has been working some 30 years without needing a bckup pump!

Just my opinion though!
 
Naomi - For information on a permanently installed back up fuel pump, see my article at: https://www.mgexperience.net/article/backup-fuel-pump.html
If the pump presently installed on your car is one of the plastic, New Zealand Auto Prod clones of the SU pumps, throw it away, the leak will only get worse as they crack over time. If you have a real SU fuel pump the banjo fittings should have fiber washers unless the pump is relatively new, in which case it will have a combination of fiber washers and 'O' rings. If copper washers have been used in place of the fiber washers, you may be able to reuse them by first annealing (heat until they turn red, then let them cool). Don't try to reuse aluminum washers if that is what is there. If you have any specific questions regarding fittings, e-mail me at ddubois@sinclair.net as I have pictures and part numbers of the various fittings.
Cheers,
 
Dave, why run the pumps separately? If you put the facet inline with the SU and power them both, the facet will do all the work unless it fails, at which time the SU will take over. No switches, no hassle.

Personally I've never found the need for a backup pump. I've had a couple SU pumps go out over the past 20 years (six cars mind you!) but they always gave plenty of warning. In the BGT which now has an electronic SU (Dave's conversion) I carry a spare pump since it will likely not warn me of a problem.
 
Wow -- thanks a bunch folks -- this truly is the place of MG Experts --Thanks again /bcforum/images/%%GRAEMLIN_URL%%/smile.gif /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]electronic SU[/QUOTE]
Moss has 4 different solid state electric SU fuel pumps for the various MGB's....original looks, no points!
 
If anyone ever hooks two of them up at once be sure to put them in parallel (side by side) and not in series (front to back) since if they are front to back and both powered at the same time then your fuel pressure will be double what it should be and fuel will overflow at the carbs. If they are in parallel then the pressure will be only that of one of them.
Bill
 
I've not had one fail. What warnings do they give you?
 
Steve_S said:
Yeah, but you have no warning when they're about to fail.
Click to expand...
I believe they click like the old points pumps; but....

...what fuel pump ever gives a warning its about to fail?
 
Steve - I hope that the spare you are carrying is also an electronic pump. If not, it probably won't work when you need it. The reason you haven't had a pump fail on you is that you drive the cars regularly. If a points style pump is not used regularly, a film will develop on the contacts and will build up enough to keep the pump from running.

As for running the backup continuously in series with the primary pump, there are two reasons not to. First, with the pumps in series, the output pressure is the sum of the two pumps and could be enough to overpower the needle valves (note - could not will). Second the two pumps probably have the same life span, so which will fail first? or will they perhaps fail simultaneously and finally, how will you know when one pump fails and you are back to square one - running with one pump and no back up? Having to change out a pump in our MGB on the side of I5, just north of Weed, in the freezing cold, with a 45 mph wind blowing and traffic roaring past at 75mph, a few feet from the car is not my idea of a fun time. When I got home, I decided that I was not going to do that again.

"I've not had one fail. What warnings do they give you?"
when a points style pump first starts acting up, a few taps with a screwdriver handle will normally get them going again. Taping an all electronic pump that has failed normally doesn't do any good.

"I believe they click like the old points pumps; but...."
Tony, if you are referring to the all electronic fuel pump, they do tick like the points style, it is just a slightly softer tick and it runs a bit faster than a points style pump.
Cheers,
 
David said:
when a points style pump first starts acting up, a few taps with a screwdriver handle will normally get them going again.
Click to expand...

In one personal instance it was a 6 oz. ball pean hammer wot got us home, then thru another day or two before we could replace the points (1975). In another it was my four pound granite "parking chock" wot got us across the second half of Alligator Alley... back when it was still an unlit two-lane (1986). WITH alligators. /bcforum/images/%%GRAEMLIN_URL%%/wink.gif
 
Late model MGB pumps may be different, but it's standard practice for many people with T-Series MGs to run a facet pump in the rear of the car and an SU up front. The SU will only activate when it senses low pressure (to put it simply), and since the facet is pumping forward into the SU, the SU basically sits at idle. If the facet should fail, the SU will begin pumping and you will continue driving without a hiccup.

You would know when the facet pump failed because suddenly you would hear the SU ticking whenever you turn the key.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Steve - I hope that the spare you are carrying is also an electronic pump. If not, it probably won't work when you need it. The reason you haven't had a pump fail on you is that you drive the cars regularly.[/QUOTE]
Dave, I don't drive ALL the cars all the time. The YB for example gets driven very rarely and that pump has not been rebuilt in its known history. The car even sat for 25 years before I bought it, and nothing has been done to the pump. The same goes for our TC. That pump sat virtually unused for ten years, being driven only a small handful of times around the neighborhood. It's still alive and well. Even the pump in my '65 B sat for a few years and fired right back up without a hitch.

I always hear people talking about points-style pumps going bad from sitting, but I've never had it happen. Maybe I'm just really lucky?
 
Steve_S said:
I always hear people talking about points-style pumps going bad from sitting, but I've never had it happen. Maybe I'm just really lucky?
Click to expand...

Sorry to jump in, not having an MG, but I never had any problems with my EType's point-style FP. I just rebuilt it recently only because I'm doing a total restoration and it was sitting there on the bench. I figured why not - easier now than sometime later. But I drove the car for a number of years and never had any problems at all with the FP. In fact the original points looked pretty good when I tore it apart.

Basil
 
"Maybe I'm just really lucky?" Yes. That and original points. What I have seen in nearly thirty years of repairing these pumps is that the original points, while they would film over eventually, were much better than the points that are available today and that even includes the points available from Burlen Fuel Systems, which in turn are vastly better than the after market points available from the usual suppliers.

Basil - you may have been better off to have dressed the contacts on the old points and reused them rather than replacing them.
Cheers,
 
Steve - "Late model MGB pumps may be different, but it's standard practice for many people with T-Series MGs to run a facet pump in the rear of the car and an SU up front. The SU will only activate when it senses low pressure (to put it simply), and since the facet is pumping forward into the SU, the SU basically sits at idle. If the facet should fail, the SU will begin pumping and you will continue driving without a hiccup."

The Facet in the rear is over powering the low pressure volute spring of the low pressure SU pump if the car is a TC, TD or early TF. Later TFs, MGAs and MGB use a high pressure pump what would probably share the pumping duty with the Facet pump and could in the case of high presure pump with a 3.8 psi volute spring instead of a 2.7 psi spring, provide a pressure that is too high.

Essentially the many T series people who are running a Facet pump in the back and a SU pump in the front are using the SU as a back up for the Facet pump. The logical extension to this is to do away with the SU pump entirely and just use the Facet pump. I stand by what I have already said about the points style SU fuel pumps, left idle for a long enough period of time, they will not run when finally called on - I have had this proven to me too many times to use a points style pump (SU or otherwise) as a back up pump.
Cheers,
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Essentially the many T series people who are running a Facet pump in the back and a SU pump in the front are using the SU as a back up for the Facet pump.[/QUOTE]
Exactly what I was trying to say! It also retains the original look of the car even though the SU pump is sitting at idle.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]The logical extension to this is to do away with the SU pump entirely and just use the Facet pump.[/QUOTE]
But then you're back to just one pump. Do you really feel that an SU pump is not trustworthy but a facet is? I've had tremendously good luck with SUs. I have never owned a facet long enough to have good or bad luck with them, but I'm sure they are as reliable as anything. I have one in my MGC as installed by the designer of the car.
 
Touche' Steve /bcforum/images/%%GRAEMLIN_URL%%/smile.gif

"Do you really feel that an SU pump is not trustworthy but a facet is?" (kind of like "when did you stop beating your wife")

I think that we are comparing apples to oranges here or perhaps talking at cross purposes. I have to be careful to state which SU fuel pump I am talking about. Generally when people talk about SU fuel pumps, they are referring to the points style pumps (that is changing rather rapidly now days and one has to be more specific). That said, yes, I would have to say that being all electronic, a new Facet pump is going to be more reliable than a points style SU fuel pump of indeterminate age (a new, all electronic SU fuel pump is also going to be more reliable than the same points style SU pump of the same indeterminate age and a new points style SU pump will also be more reliable that the one of indeterminate age). As I said in my previous post, a points style fuel pump, SU or other make, that sits idle long enough will eventually develop a sufficient thickness of film to keep it from running. Any all electronic pump will tolerate long period of idleness much better because there is nothing to film over and stop it from running (if it is left long enough I suppose that the diaphragm will stiffen to the point where the pump won't run, but that is going to take significantly longer than it does for points to become non conductive. That is the reason that it doesn't make sense to me to use a points style pump as a back up for an all electronic pump, regardless of brand.

Comparing the Facet pump to the all electronic SU fuel pump, I suspect that they will both remain reliable for about the same length of time. I would probably give the SU pump the edge on that one because the Facet pump uses a metal shuttle moving back and forth in a metal sleeve to pump the fuel and is thus more prone to wear than the diaphragm in the SU pump. I had a Mazda pickup for a number of years with a Facet pump in it. The pump died at around 100,000 miles, but unlike the points style SU pumps, it kept running, it just wouldn't pump sufficient fuel to keep the truck running. Since the all electronic SU pump doesn't have any components that suffer from mechanical wear, they should keep on running until such a time as the diaphragm either becomes stiff with age or tears (something I have never seen - tearing that is). That said, I earned a living by repairing electronic systems, which always makes me a bit leery of things electronic /bcforum/images/%%GRAEMLIN_URL%%/crazy.gif
Cheers,

PS. I will be sending you an e-mail about another subject that we have a common interest in - the Saint Francis Dam.
 
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