AC Mechanical Fuel Pump Kits

[Alan Stanley]

Has anyone recently installed a new diaphram into the mechanical fuel pump?
Do you know if it was NOS (unused old stock)or a recently manufactured item?
Is it suitable for modern unleaded fuels and maybe alcohol blends?
Where did you obtain the kit and approximate price?

Comments welcome

[robert lintott]

I think I bought a kit from " The Carburettor Hospital Ltd" tel 01702 203 286, in Rochfiord Essex . They have a website carburettorspecialist.com or carburettor hospital.co.uk ( do not look right!) . They seem to have a vast stock and were very helpful Bob Lintott

[Forumadmin]

I always carry a tested spare pump in all my Jowetts. It is the one part that seems to stop cars dead. I also recently was sent a repair kit by a member. I will have a look at the box. It looks like old old new stock or ne old old stock, however you look at it . The packaging is worth more than the contents to some people!

[robert lintott]

The fuel supply has been the source of unreliablity on all three Javelins I have owned. It is particularly a problem starting . the carburettor bowls empty on standing for more than a few days, churning the starter to fill them is a toss up between flattening the battery and starting the engine . Hence using the pump lever or spraying fuel down the air intakes . i am sure that if Jowett had survived they would have installed an electric pump at the tank , as I may do. and is the Jupiter system?

I know the purists will say originality matters, but not if the design can be improved ? Bob

[Alan Stanley]

You can also just fit a choke or bonnet bowden cable to the lever on the mechanical pump to prime it with a few strokes from inside the carwithout opening the bonnet.

As for electric pumps I am currently dumping the SU on my Jupiter with its points and trialling a modern diaphram electric pointless pump, but at the back of my mind are more comfortable with the mechanical pump as on my javelin

[Forumadmin]

We fiited a modern electric pump of supposedly good quality for the Monte rally. It packed up. Never again wil lwe use such modern stuff. It may be that the electric charging system is not smooth enough and blows the electronics.

[jowettgeoff]

Like Keith, I Also had nightmares with SU electric pumps. Having converted my rally Jav for reliability (hah ), I had problems on one of the Pirelli Marathons at the top of a mountain pass somewhere in Italy (according to Frank, my navigator!). I had an old one for spares in the boot, so proceeded to try and mend it, but managed to lose the small contact spring in the gutter. Eventually we managed to cobble together a working one, but 30 minutes had been lost, which gave us a time penalty, thus losing our chance of prize. I subsequently fitted two 'high performance' ones under the rear of the car, with a changeover switch on the dash. But if ever the car is stood idle for a few weeks, these refuse to work without a hefty tap from a small hammer (Oh how I wish I hadn't fitted them UNDER the car!). Meanwhile, the mechanical pump on my regular Javelin has performed faultlessly for more than 25 years. In defence of the SUs however, I have to say that the one on my Jup is probably more than 20 years old, and never misses a beat. Mike Smailes successfully used a solid-state pump on his former Jup. I do have an electronic one on the shelf which ticks just like an SU, so that'll go on the rally Jav when I get round to it.

[Keith Clements]

Just to clarify, John Blanckley and I had problems with a 'solid state' electronic pump, not the SU or contact breaker type. So I am wary of fitting new technology.

I have had to renew the points on my SU (twice) but have not renewed anything else over 40 years of use of my Jupiter. I did fit a capacitor (see http://jowett.net/forum/viewtopic.php?f=1&t=1980) on the second fit which was supposed to reduce contact burn. Amy did have a problem with the SU when she let the car run out of petrol when on her way to a wedding. Subsquent investigation showed that the pump was OK and that an air lock may have been the problem. We had similar problem with the SC on commissioning where we had to presurize the tank to force air out of the line and prime the pump. This was done with a rag helping to seal the filler into which we gave a short blast with an air line.

However, I do carry a spare petrol pump and on the European trip with enough pipe to run from the tank to the engine just in case we needed to bypass the system due to poor petrol , blocked or broken pipe or failed pump. The pump was also tested before leaving, unlike one owner on the Jupitour who carried a rusted spare.

[jowettgeoff]

Pressurising the petrol tank sounds fun. Hope you got Amy to do it while you sheltered a few streets away