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Early electronic SU fuel pump failure ?

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Ed_K

Ed_K

Jedi Knight
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I wrote the subject line as a question on purpose.
...
I installed one of those electronic, negative ground, SU fuel pumps 18 months ago. It failed in my driveway before leaving for a drive on Friday.
The supplier should replace it for free since it is less than two years old but it is an electronic pump and I was expecting that it would last a lot longer than 18 months.
Mechanically the pump is fine; no debris inside, moving the arm up with a screwdriver while covering the intake results in a vacuum so I know the electronics have failed.
Has anyone else had a similar experience with this electronic SU fuel pump ? Without points, I expected this to last for years with trouble free operation, not just 18 months ?

Did anyone else have a similar experience with this type of pump ?

Ed
 
No ED,
No such rotten luck with the pump. Mine has been in since they first came out with the NEG Gnd unit and is still going strong.---Fwiw--Keoke
 
Hi Ed,

The one saving grace of the mechanical fuel pump is that you usually can find and replace the failed part. Since a relatively inexpensive component is usually the culprit when an electronic gadget fails, there must be a way to identify and replace the, usually very inexpensive, faulty circuit element in your pump.

To the general group, where would you take an electronic gadget to be diagnosed and fixed? Is there someone on the list that has that expertise? That’s how the BJ8’s electronic tack was diagnosed and a commonly deteriorating part was identified for all to easily and cheaply replace.

Good luck and all the best,
Ray (64BJ8P1)
 
To the general group, where would you take an electronic gadget to be diagnosed and fixed?

Well Ray, it depends on the type gadget. For example.
Radios go to the radio repair shop.
Electronic ignitions go back to the vendor.
Fuel pumps in warranty go back to the vendor.
Fuel pumps out of warranty go in the trash bin
& get replaced with new.

ONE last thought: There is no elctro mechanical device such as a relay or an original points type fuel pump that has the reiability of it's modern all electronic counterpart.---Fwiw--Keoke-- :hammer:
 
Ed, Go here, Dave DuBois is an authority on SU pumps, among other things and always willing to offer information relating to a problem! PJ

https://homepages.donobi.net/sufuelpumps/
SU Fuel Pumps & More Document
 
Thanks for that link.
He has a lot of useful information there.
I have bookmarked the link for future reference.

:thumbsup:

Ed
 
Hi Ed,

Did some asking and a knowledgeable friend informed me that the printed circuit would be very difficult to repair. He did inform me that, in a number of pumps he worked on that sat for a period, the diaphragm would stiffen and require readjustment to perform. He indicated that, in many cases, this was the only thin wrong with many pumps that were trashed. Where the electronics were bad, he indicated that he had success in changing the pump to work with a points-base head. In any case, don’t follow Keoke’s advice and trash the unit, as it can always be useful for parts.

All the best,
Ray (64BJ8P1)
 
I am not trashing it.
The pump was still under the 24 month warranty and is taking a cross country trip via usps to the left coast for replacement with a new one at no cost to me from our usual supplier.
...
It was an electronic component failure. I did not unsolder anything as I did not want to take a chance on the warranty not being honored but when 12 volts was applied on my workbench, nothing moved and it did not draw any current. The plunger moved freely and if I covered the inlet hole with my thumb and then worked the plunger with a screwdriver a few times, it would draw a good vacuum against my thumb. I noticed a lot of condensation on the printed circuit board. That moisture probably led to the component failure. We have high humidity around here most of the time.
...
I think I will convert my original points pump to solid state and install it as a backup as others have done. It is already paid for. I may as well use it.

Ed
 
In any case, don’t follow Keoke’s advice and trash the unit, as it can always be useful for parts.

Now there you go misquotin Keoke.---
grin.gif


Keoke did not say nothin about "Trash the unit". He said they go in the trash bin. Now if you want to rescue some parts off it later it's right there in the trash bin OK---Keoke-- :laugh:
 
I've used the 'DuBois' circuit modification on several pumps and they are all working after 4 years. Two Healey's, two MGB's, a MGA, a Lotus Elan. One of the Healey pumps I bought at Carlisle for parts, by chance I hooked it up - no go, but would work if I bypassed the points. So I took it apart the points were shot, German make - no parts available, so I filed & polished the old points reinstalled with the DuBois transistor and it's been in my Healey for 4 years - working fine. I used to carry a spare and even considered installing a inline backup but haven't had to.
Regards, Bob
 
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