Fuel Pump?

[stretchit2]

Today I was driving along at about 70 miles an hour, when I noticed the car started to miss. It felt like she was starving for fuel. Before long she quit running completely. I pulled off to the side of the road, and when I tried to restart her, I noticed the familiar tick tick tick of the fuel pump was not there. Once home, I pulled the rear seat out to expose the fuel pump, I then turned on the ignition and she fired right up.
Less than a year ago I had a new SU solid state fuel pump installed and she has been running trouble free since then. Is it possible the pump has gone bad or could it be something else? Quite frankly I'm a little afraid to take her out for a test drive for fear of getting stuck. I would appreciate any advice on how I might troubleshoot the problem.
Cheers
Jeff

 

[BigGreen]

The pump comes in two or more types, one with points, one electronic
Points sometimes wear, like the ones in the distributor
Look for the filters they may be clogged up
Also some rust from the tank can block the intake

Hans

 

[Randy Forbes]

Check too, that the tank is still vented via the gas cap. If that gets plugged, the pump will eventually pull more vacuum than it can overcome.

Sucking up debris and blocking the pickup tube is more probable.

 

[andrea]

I SUBMIT TO BCF members ONE new SIMPLE MOD to SU pump
https://ttypes.org/ttt2/pdf/TTT2-Issue9.pdf
see page 10 and more articles on SU pump mod on the previous
issue August 2011
it consist on a single NEW semiconductor called TRANSIL
that avoid spark from the points, it will be mounted into the SU pump simply unscrew two screw
- I have ordered and received
two of this - one for my AH 100/6 in restoration
and one for my MG TD at the moment i haven't any extensive
period of driving on my MG but the costs and mod is so
ease and cheap that I can suggest the MOD that is also less invasive that electronic MOD and more simple to fit
Cheers
Andrea
no financial interest on Transil Mod

 

[big6]

What type of pump gasoline are you using? I have experienced the same symptoms you describe with my TR6 due to E10 gasoline containing 10% or less ethanol. (According to the decal on the pump) The first clue was rust particles in the fuel filter. The next were leaks at the rubber fuel lines connected between the metal lines and soft rubber lines that would collapse under vacuum and finally small particles of rubber in the fuel filter and float fuel valve. My older electric fuel pump and fuel pressure regulator diaphragm failed. (I am running triple Stromberg carbs)

The rust comes from the ethanol (water) attacking the metal tank from areas that the zinc plating is missing. The older fuel lines were attacked by the ethanol as well.

I installed a glass fuel line filter so I can see any accumulated rust sediment. The rubber fuel lines were replaced with the ethanol approved fuel lines. The electric fuel pump and pressure regulator were replaced with the later ethanol updated models. Finally on the TR6 the hot idle compensator seals swelled needing later style ethanol tolerant seals. I have had gross jets for the past 18 years so the float needle was not an issue.

The TR6 seems to run without fuel starvation now but not sure if I have changed all carburetor parts that are not ethanol tolerant. Time will tell.

I was at the auto parts store and noticed that Stabil has an additive to counter the effects of 10% or less ethanol E10 gasoline. If your fuel with 10% ethanol is older than 2 – 3 months your engine will run lean due to water dilution. This can happen even with using Stabil or other brand fuel additives. With older fuel in your tank you may also need to install an octane booster. https://www.fuel-testers.com/e10_safe_gas_additives.html
This seems to be a good article found about the gasoline issues…

I have also experienced the same issues with my Ryobi weed eater and Stihl chain saw…

 

[RAC68]

Hi Andrea,

I read with interest about the Transil diode modification to the SU pump. Having previously transistorized the SU’s triggering points via the approach extended by Dave DuBois over 20 years ago, I have experienced tungsten point failure resulting from not passing enough voltage to burn off forming oxidation (the reason Dave hasn’t backed the modification for the past 15 years). Applying a Transil diode may be a very effective alternative for extending point longevity while still applying sufficient voltage to clean the naturally forming oxidation when tungsten points are unused for any period.

Also, I have never been comfortable with the solid state approach that SU has taken in which the circuitry functions on a timing basis and not on the travel of the diaphragm as with points. Additionally, there seems to be no power protection circuitry included and failures seem to have been the result. I like the Transil approach as it has none of these issues.

All the best,
Ray (64BJ8P1)

 

[Bob_Spidell]

Hi Andrea,
...

Also, I have never been comfortable with the solid state approach that SU has taken in which the circuitry functions on a timing basis and not on the travel of the diaphragm as with points. Additionally, there seems to be no power protection circuitry included and failures seem to have been the result. I like the Transil approach as it has none of these issues.

All the best,
Ray (64BJ8P1)

The two SU retrofit kits and two solid-state pumps I've bought use a magnet pushed back-and-forth by the diaphragm shaft to trigger a Hall Effect switch; an electronic equivalent of the points and throwover mechanism of the original pumps (Pertronix Ignitors also use magnets and Hall Effect switches). They're definitely controlled by the travel of the diaphragm. The kits didn't work out well, one of the SU-supplied SS pumps has powered my BJ8 reliably for many years but the other isn't behaving well in our BN2, but there may be issues in the fuel tank or lines. Can't say if there's any overvoltage protection but they are polarity sensitive.

Never heard of a 'transil' before; according to Wikipedia it's a pair of Zener diodes in series oppositely biased for polarity insensitivity (think 'transil' might be a trade name). A Zener diode--aka 'avalanche' or 'breakdown' diode--will allow some voltage before shorting, so your theory about the transil doing a better job of cleaning the points makes sense to me.

 

[57_BN4]

they are called TVS or transient voltage supressors. Not all are bi-directional though. https://newzealand.rs-online.com/web/p/tvs/5438400/

 

[stretchit2]

To my fellow Healey Owners,
First of all thanks to everyone for their prompt replies and expert advice.
Now for my findings........

It wasn't fuel after all. I changed my fuel filters, changed my gas cap, and it ran fine at first, but at speed it would hesitate and then eventually it would stall, and it felt like and sounded like it was starved for fuel. I then surrendered and called a mechanic friend of mine who is somewhat of a Healey genious. I explained the symptons and he recommended that I disconnect the white/black wire that goes from the battery disconnect switch to the coil, to check and see if that switch had gone bad. Started the car, took it out onthe freeway, got her up to speed and she ran like a top. He told me that he has seen that happen quite often. I won't soon forget.

Thanks again for all the help, Merry Chritmas and Happy Holidays to all,

Jeff

 

[pkmh]

Interesting result there stretchchit2 regarding the cutoff.

I have been experiencing similar issues with stalling in the past. But am in the process of revamping the entire fuel system, including a new gas tank, new fuel pump, blowing out the existing fuel line not to mention numerous other tasks performed thus far.

I reconnected my cutoff switch before my stalling issues started up again, but I will rather hold off blaming my cutoff just yet. But that seems to be yet another possible cob in the equation.

In my case, I should soon be finished with my fuel system rebuild and take it from there. I will certainly keep your results with the cut off in mind if my problem should still persist.

I only hope what I am doing will be my result of stalling. I'm running out of possible causes!

Thanks for that.