Which Fuel Pump Should I Choose

[malky1965]

I have just found out that the fuel pump fitted to my V12 OTS is an aftermarket one and I want to replace it with the proper spec but I see that SNG Barratt have the original one with points and also an electronic one, both of which look the same.

My question is, which is better and why?

Regards
Malky

[chrisfell]

Electronic one, no question.
The original used points, which arc and wear and eventually fail.
The new one uses solid state technology which doesn't.
If that was available and cheap when the E-Type was designed it would have been used.

Do not listen to the 'original or nothing' concours tarts, go with the best option for your car, the one that will allow you to get in and turn the key and drive whenever you want, and not whenever the fuel pump decides you can.

[mgcjag]

Hi Malky...totaly agree with Chris...you even get the same ticking sound.....there is also a rubber foam cover that surrounds the original type http://www.sngbarratt.com/CatalogueProd ... 52&a=16601

[MarekH]

Dear Malky,

The actual fuel pumps are the same in each case. The difference between the two is in mechanical and electrical wear as the points operate.

With the old style pump, an electric contact is made and broken and the full curent required to run the pump (both pumps - there are two independent pumps running) is switched at the points. This is a not insignificant current and it causes wearand is subject to corrosion which affects the full current transmitted.

The electronic version is identical, save for the fact that only a tiny current passes through the points and this is then used to switch a large transistor on and off. This opens and closes the passage of the large current needed to operate the pump exactly as before. The advantage here is that the electrical wear and tear at the points is removed and put on the shoulders of the transistor. So long as the transistor is operated well within its design specification limit (and it is chosen with this in mind), then the electrical wear and tear of operating a high current mechanical switch is completely designed away for ever.

As such, the electric version will be better.

Neither pump is fused on your car and both run through the ignition switch. You may like to consider using a fused relay to bypass the ignition switch for such a high current load. The forum has threads covering this already.

kind regards
Marek

[malky1965]

Thanks for the quick replies guys, as usual on the forum they were very informative, so electronic it is then !!!

Thanks Again

Malky

[christopher storey]

Before you buy anything, have a word with Andy Rayner at Hutson's , who has experience of having supplied the electronic ones . If you want a blood chilling sight, he is probably still able to show you the V12 double one which went on fire fortunately without destroying the car. As far as the points type is concerned, the first 500,000 miles of my motoring career between about 1962 and 1970 was propelled exclusively by SU pumps and I never had a failure. Similarly I have 5 cars fitted with them now and apart from one blockage with silicon sealant ( I've no idea where it came from ) they have been 100% reliable. Incidentally, the arcing across the points referred to by marek H is minimised by the capacitor across the points which was incorporated in all of them from about the 1960s onwards