Classic cars forum & vehicle restoration.

[Ray White]

I have an old (possibly original) 12 volt, positive earth SU fuel pump that was fitted to the car. It was working O.K. but I will not want to rely on it... so what should I do?

I could get a rebuild kit from Holden and refurbish the pump and fit my new transil...

... OR

I could buy a new electronic SU pump but I have heard of reliability issues with new pumps. Some apparently fail after quite a short time. Is this really the case?

What is the best way to go?

[ukdave2002]

Hi Ray

Firstly the SU fuel pumps are not polarity sensitive, unless they have a diode fitted (the diode prolongs the life of the points, but can be removed or reversed in the event of a polarity change)

The electronic pumps do nothing more than replace the points and if the electronics fail you are stuck!

There is a rebuild video on this link (bottom of the page):

http://morrisregisterspares.co.uk/?product=epk700-service-kit-su-fuel-pumps

I'd rebuild the original

Dave

[alastairq]

I have used the Facet solid state pumps for decades, without failure.

Not original to look at, but fitted to all the vehicles I used in competition....where reliability/repairability was almost paramount.
Whilst SU pump look nice and guccily vintage...I find them bulky[especially where space is at a premium?].
But, hey, that's just me!

BTW, on an SU pump, is one not stuck if the points fail too?


If getting home again under one's own steam is an issue..then why not fit a schrader valve into the fuel filler..then if the pump fails, one can use the obligatory air pump which one ought to be carrying, to slightly pressurise the tank....that'll push some fuel through nicely too.
_________________
Dellow Mk2, 1951 built, reg 1952.
Fiat 126 BIS
Cannon special [1996 registered. Built in 1950's]
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Ford Pop chassis, Ashley 1172 bodyshell, in pieces.

[Ray White]

Thank you Dave and Alastair. Two perfectly reasonable views that differ but perfectly sum up my dilemma.

Since seeing my business crumble to ruins I seem to have lost my self confidence. I am now nervous about changing the MG too much. While a new / different pump would be one answer, there are aesthetic reasons for keeping the original SU.

As we now have a very small income my wife and I are agreed that economies need to be made. So, I thank you Alastair for your input but on this occasion I will go with Dave's suggestion that I rebuild the pump that I already have.

That is a really good video of a SU pump rebuild and I will follow it closely. I have even been given permission by the Boss to use the dining table (so long as I cover it)!!

[Ray White]

First problem. I have removed the plastic cap and the first thing I noticed was that the points are different. The pump I have (probably 1949) has A single points set. All the rebuild kits I have seen have a twin points set up.

What do I do ?

[DM]

[alastairq]

I really only wanted to make the point that solid state electronics need not be unreliable.....mind, I will say that a Facet pump is one heck of a sight cheaper than the equivalent SU....
I too, have an SU or two kicking around in a box somewhere...with nothing I can think of to use them on? Oh well, maybe time will tell?
I am sorry to read your business has collopsed....
Still the only way is up???
_________________
Dellow Mk2, 1951 built, reg 1952.
Fiat 126 BIS
Cannon special [1996 registered. Built in 1950's]
----------------------------------------------
Ford Pop chassis, Ashley 1172 bodyshell, in pieces.

[ukdave2002]

Ray ; all the new SU points are dual and a direct replacement for the single points; it aids reliability.

We (MR spares) virtually had to virtually give away the last single contact point that we had, as the dual points were only a few pennies more!

Personally I stick with the original SU, they are simple to fix and set up and only need a bit of attention every 20,000 miles or a points clean if the vehicle is left standing.

The Facet pumps Alastair mentions get great reviews and you could buy one for not much more than the cost of an SU rebuild kit! but you wold miss the reassuring tick of an SU !

Dave

[Rick]

[Ray White]

[Ray White]

[lowdrag]

Having owned Jaguars for nigh on 40 years I have always carried a spare SU pump and, on many occasions, helped someone out who had come to France and broken down. All I have asked is that they send me a replacement, which they have always done, and the latest on the shelf can be fitted to either negative or positive earth cars I see. But in most cases a quick rub with an emery board or such will get it ticking again. Assuming you have first tried hitting it with a spanner that is . But it does seem that the modern electronic ones are very reliable, although 20 years ago the first ones were certainly not. I have an electronic immersed one in mine right now.

[norustplease]

[/quote]

I remember reading about Facet pumps when I had my P5B years ago, there were comments floating around online about them being quite noisy?

RJ[/quote]

Facet pumps are quite noisy if not fitted with some kind of resilient mounting. My Traction had an SU pump (new) fitted to replace a Facet (no mechanical pump) which I deemed too noisy, it being rigidly fitted to the chassis. The SU, however, let me down on several occassions for no apparent reason and so I refitted a new Facet on rubber mounts. There is a little noise when the ignition is initally switched on, but that subsides to almost nothing when the pump has filled up the system. This is quite useful, especially when the car has been sat for a couple of weeks, because you then know that it is time to press the button to start the car, and don't waste essential battery power churning the engine over to pump fuel though the system as you would with a mech pump.
_________________
1953 Citroen Traction
1964 Volvo PV544
1957 Austin A55 Mk 1
Boring Tucson SUV

[Penman]

Hi
If by any remote chance it proves not possible to refurb your SU, you can always leave it in place as a straight through filter, and dummy wires attached but without it's mechanical parts, valves, diaphragm etc , and then fit another pump out of sight along the fuel line.
_________________
Bristols should always come in pairs.

Any 2 from:-
Straight 6
V8 V10

[Ray White]