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MG MGA - Fuel Pump - Keeps ticking!

Hi there,
I first post for a while, since my MGA has been running smooth...
The other day I took the car to work, and on the way back is started to overheat (stuck in traffic), and getting home it eventually vapour locked and stopped.
The when I tried to start it again, I realised the fuel pump would tick but would not stop (as it usually does) and continues to tick forever. I thought that this was something to do with the vapour lock condition so I didn't take much notice of it.
Yesterday I took the car to Terry (also from South florida) to do some work on the car and the same thing happened.
I checked the usual suspects, and there is no Fuel pouring out the overflow tubes or anywhere to be seen. The clear plastic fuel filter is full of fuel, but it keeps ticking.
In this condition I was able to do 80miles yesterday with no issues.
Any suggestions why this may be happening? Could there be air in the system? maybe debris in the pump filter?

I just don't want the fuel pump to burn out unnecessarily.

Gonzalo Ramos

Gonzalo, when this happened on my car, it was caused by a bit of crud in one of the pump valves. This causes fuel to be pumped down the line, and then, because the valve doesn't shut properly, the fuel is sucked back again, causing the pump to tick continuously. I put my fuel filter between the tank and the pump to stop crud getting to the valves; mine is an after-market fuel pump with no internal filter. Hope this helps, Lindsay.
Lindsay Sampford

Could be crud in the check valves as noted. Also if you are not dropping fuel on the ground somewhere, check for an air leak on the input side of the fuel pump. Odd that you would be able to sustain speed over 80 miles though with the pump acting like this.
Chuck Schaefer

Gonzalo, I had this problem a while back and checked everything without success. Whilst stationary with the engine off it would tick every 5 seconds or so. In the end someone suggested (afraid I can't remember who but there's stuff in the archives on this) that I take out the brass disc acting as a one way valve on the outlet side of the pump and gently smooth it with fine wet and dry. Did the trick for me.
J H Cole

Gonzalo, Have you removed and cleaned the tank. Years ago a friend with a TR 6 started having fuel problems just like yours. After fooling with the fuel pump we happened to look down in the tank; remember TR 6 have that flip top cap. Apparently someone in the past who owned it had children and they liked to drop things down in the tank. We found marbles, toy soldiers and even a large spring that looked like it came off a porch swing down in the tank.
Once it was all cleaned out he never had any fuel problems again.
Richard Taylor TD3983

I am going to look into all of this this weekend and will report on the findings! ; )
Gonzalo Ramos

Well, here are my findings, and I did not manage to fix it yet.

I believe I have an aftermarket pump, cos I was not able to find any SU markings. In any case it is pretty similar to the original and tick the same.
On the top chamber there is a fine mesh-like filter (like on the carbs) held in place with a spring. This filter was clean.
On the other side there is a circular piece of rubber which firts over the actuator. My impresion when I turned it on is that the actuator is not performing all its travel, so I think it may be suck....cos it certainly sounds quieter than usually.

there is a second chamber underneath where the succion is performed, but did not have time to open it as I got caugh by me condo's security... ; (
Will try to sneak again tonite to give it another try...


Gonzalo Ramos

Ticking pump seems to be an on and off thing on repaired pumps anyway. The perfectaly good reco pump on my Riley sometimes gets very enthuastic when driving and behaves it's self idling. A couple of minutes later it's behaving again for the rest of the driving day. The tank is like new inside and there is a large inline filter before the pump.
The misteries of life. Sean
P.S. I carry a spare pump !
S Sherry

Well, unfortunately there is bad news!

I took the pump off the car just now and inspected it.
I seems like the rubber diaphragm has several holes. ; (
Hence it kept pumping and the pressure never built up!


I also found the whole pump body and electronics flooded with fuel, and all the eletronics are full of black soot...probably some minor ignition with the points sparks!!
It is currently drying and although I think the electronics may be ok, I don't think I will be able to find a replacement diaphragm for this old aftermarket pump.
Since I want to be on the road again soon, I am going to look at a cheap aftermarket pump.
Any recommendations from the local AutoPArts / NAPA store apart from the ones Barney suggests?


Thanks!
Gonzalo
Gonzalo Ramos

and the pic

Gonzalo Ramos

and another. anyone recognize this pump?

Gonzalo Ramos

Gonzalo - The pump you have is a Walbro pump. You may be able to get repair parts for it at: http://www.autoperformanceengineering.com/html/bel_pump.html Cheers - Dave
David DuBois

Seems there is a replacement kit for $13. Do you think it is worth repairing or better to buy a new one? Especially considering all the electronics were submergerd in fuel...
Gonzalo Ramos

The electronics should not be damaged by immersion in fuel, spray them off with something like CRC Brake Clean. For $13 I would consider it worth a try. Other than what I have seen on their web site, I don't know anything about the Walbro pumps. Cheers - Dave
David DuBois

I need a fast solution so I am going to buy an aftermarket pump following Barney's site guidelines.
I took me some research but now it is clear that the one I need is E8016s which is available at all advance autoparts stores and is 50dollars.

My question now is;
Is it worth adding an in-line filter before the pump to protect the pump somewhat since I believe this pump does not have an internal filter?
Like barney does on his site?

I already have one of those cheap clear plastic filters in the engine compartment before the carbs.
I am just weary of restricting the flow too much, although I understand that these filters have virtually no pressure drop across them.

I would like to keep the one in the engine compartment cos I allows me to see if fuel is getting to the carbs and allows diagnosis of problems...
Gonzalo Ramos

I would be leary of the cheap clear plastic filters. I have heard horror stories of plastic filters developing leaks and causing fires.
Richard Taylor TD3983

So I bought a new aftermarket pump and installed it tonite.
I had to rethink the installation position slightly because this one protruded too far downwards.
The bonus is that is came with its own fuel filter at the inlet.
For future reference it is an Airtex E8016s (2 - 4psi) from an Advance autoparts. Cost $55 with tax.

I also took the opportunity to change the flexihoses.

Connected the electrics and voila! It looks like it works. I lost the ticking sound of my car though, which gave it it's charisma as it is virtually silent.

Now, my question is whether the pump is supposed to stop when it reaches a certain pressure like the bellows?

This one seem to just run constantly. It this normal or am I missing something? I can feel it vibrate when you touch it.

It is difficult for me to check if it is working right. I just started the car and it seemed to work fine, but I am not sure I waited enough for the float bowls to empty.


Gonzalo Ramos

Try disconnecting the fuel line just before the carbs and let it pump into the usual glass jar to see how it delivers: volume and free of air bubbles.

Ralph
Ralph

Gonzalo,
I use the same pump. It runs all the time, but it is quieter when the float bowls are filled and pressure is built up.
Ed Bell

Ok, cool. I will do the jar test and then take it for a drive as soon as the tropical storm blows over florida.

Don't want to have the MGA underwater, it may dissolve! ; )
Gonzalo Ramos

Be careful with the $50 aftermarket low preasure fuel pumps. Based on my experience they last about 1-2 years and then die. I always kept a spare with my tools.
R Egge

By some first hand experience, the square and noisy Facet fuel pumps had some reliability issues in recent years, some of them bad right out of the box. This may have been resolved (maybe) with change to the black body update model.

Also by experience, the round "Airtex" type pumps (look like a large fuel filter with wires) have run reliably (and quietly) for 100,000+ miles. Be sure you get the low pressure model (2.5 to 4.5 psi). These will commonly (not always) come with a small filter included. The intake filter should be used to honor warranty requirements. If you have a dirty fuel tank you may want to use a larger filter.


Barney Gaylord

Yes, this one is the Airtex like the one on your site Barney, and installed with the little filter it comes with.
Originally the tank was pretty rusty inside and full of particles but I have cleaned that now, and just get some minute grains in the floatbowls from time to time.

It is indeed the low pressure pump 2.5 - 4.5psi.
I had too look at the Airtex specs and references to find the right ref no.

I am counting on the time proven reliability of this pump based on Barney's experience. However I am not sure if I will reach the 100k miles... But will try to... ;)
Gonzalo Ramos

This thread was discussed between 20/09/2010 and 30/09/2010

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