[Healeys] su pumps again

[josef-eckert at t-online.de]

The rubber comes first to the petrol and the plastic foil is opposit on the magnet side of the pump.
Josef Eckert


-----Original-Nachricht-----
Betreff: Re: AW: [Healeys] su pumps again
Datum: 2016-11-23T10:37:26+0100
Von: "Oudesluys" <coudesluijs at chello.nl>
An: "josef-eckert at t-online.de" <josef-eckert at t-online.de>, "Austin Healeys List" <austinhealeyslist at gmail.com>

As the rubber in OE diaphragms is protected and separated from the 
petrol by a special plastic foil membrane, you should not have to worry 
about modern fuels.
Kees Oudesluijs


Op 23-11-2016 om 7:10 schreef josef-eckert at t-online.de:
> I know SC Parts or LIMORA in Germany still have a batch of NOS tripple layer replacement diaphragms in stock. They are still in the original "BMC" package. I can´t guarantee these are better than the actual replacements available at Burlen, as modern fuels can be more aggressive to these materials.
>
> Josef Eckert
> Konigswinter/Germany
>
>
>
> -----Original-Nachricht-----
> Betreff: Re: [Healeys] su pumps again
> Datum: 2016-11-22T23:53:40+0100
> Von: "Austin Healeys List" <austinhealeyslist at gmail.com>
> An: "Oudesluys" <coudesluijs at chello.nl>
>
> My car had a generic 'modern' plastic pump which worked fine but isn't
> quite kosher so I got a new SU pump from Burlen and that is where I
> discovered the diaphragm issue. It really does let quite a bit of
> petrol smell through- enough for me to take it apart and look for the
> leak. Burlen sent a replacement diaphragm which is, of course, no
> better.
>
> If you have a used 60 year old triple layer diaphragm for sale I'd be
> interested in upgrading my new one!
>
> The best design I have seen is an Italian copy that had a single layer
> clear plastic diaphragm and also a plastic toggle inside the points
> which is so much simpler than the mousetrap. Been in a Bn2 for longer
> than I have been alive and only needed a replacement inlet fibre
> sealing washer to stop a leak.
>
> Andy.
>
> On 11/23/16, Oudesluys <coudesluijs at chello.nl> wrote:
>> I have not come across the single layer diaphragms. I have seen offered
>> on ebay new dual layer ones from China and the UK. So far I have had
>> enough scrap pumps of the wrong type to provide enough good triple layer
>> diaphragms for the ones that were fit for a rebuild as the so called
>> High Pressure type I want, AUF301 or W/AZX1307/8 or equivalent, so I
>> have no experience with the modern replacements.
>> The permeation of petrol will probably very, very little if any, so I
>> would not worry about it. Some modern rubbers withstand all fuels and so
>> as long as these are used it will probably be OK. Time will tell. Anyway
>> the pumps cast iron coil housing and the space on top under the bakelite
>> cap over the points assembly is vented.
>> As the old triple layer diaphragms seem to last for ever I would not
>> replace them other then when they have become hard and cracked or when
>> the thin plastic membrane that keeps the petrol away from the rubber is
>> damaged.
>> Kees Oudesluijs
> 
>
>