Electric fuel pumps

[Graham]

Carrying on from the discussion, what is the difference between a transil and a capacitor? Can a larger transil be used in the distributor in place of a capacitor? If so, it could make electronic ignition unneccessary. I have no idea, but a few of you out there may be able to enlighten me. Graham TC3107 Buckingham Sent from my iPad

[Peter Cole]

Graham, The simple answer is no! In the case of the pump the stored energy in its coil is a problem. Without some means of containing it it will cause a spark across the pump contact each time they open. In doing so each spark will erode a tiny part of the contact material and the contacts will quickly deteriorate. In the 1930s when SU designed our 'Type L' pump they originally used a second winding of resistance wire wound over the main coil to damp the stored energy. This wasn't a particularly effective spark suppressor. Later they tried a capacitor, then a diode which rendered the pump polarity sensitive and finally a voltage dependant resistor. None of these devices work well. Burlen Fuel Systems, who now own the SU name, finally stole my application of a Transil which is a very effective, non-polarity sensitive, arc suppressor which significantly increases the life of the contacts. In the ignition coil stored energy is used to convert the 12 volt battery voltage to around 500V, which is further increased by the turns ratio of the coil to around 20,000 volts to supply each plugs in turn via the rotor arm. The capacitor in the ignition circuit essentially slows the rise of the ignition voltage whilst the points open, so that once they are open sufficiently wide they cannot be bridged by a spark. A Transil in this application would prevent the production of the necessary high voltage as it would absorb all of the energy store in the coil at the end of the dwell period and there would be no spark. Similarly if the capacitor is defective all of the stored energy in the coil will be dissipated in an arc across the points the instant they open. Eric Worpe, of this list has studied the ignition capacitor in great detail. If your capacitor has LUCAS stamped on it, and it is a genuine Lucas part, it is probably 50 years old now and beyond its useful life. If it is a modern repro with LUCAS stamped on it it is probably a poor quality, unreliable component from China. Eric has sourced a modern capacitor that will significantly enhance the reliability of your ignition circuit. I hope this helps RegardsPeter

On Tue, 19 Jun 2018 at 20:10, Graham graham47tc@btinternet.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote: [u][/u] Carrying on from the discussion, what is the difference between a transil and a capacitor? Can a larger transil be used in the distributor in place of a capacitor? If so, it could make electronic ignition unneccessary. I have no idea, but a few of you out there may be able to enlighten me. Graham TC3107 Buckingham Sent from my iPad

[Joe Curto]

Here in USA a fellow well versed in T series cars  in New Hampshire who  has sourced a manufacturer of ignition Capacitors and has made them to spec and improving quality , he also makes Vacuum advances for later Lucas distributors  He also does all Lucas and  T series distributor  rebuilding  . If any interest  let me know and I will pass on his info Joe Curto 718-762-7878 www.joecurto.com -----Original Message----- From: Peter Cole pcoleuk@gmail.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> To: Graham graham47tc@btinternet.com> Cc: MG-TABC List mg-tabc@yahoogroups.com> Sent: Tue, Jun 19, 2018 4:17 pm Subject: Re: [mg-tabc] Electric fuel pumps   Graham, The simple answer is no!  In the case of the pump the stored energy in its coil is a problem..  Without some means of containing it it will cause a spark across the pump contact each time they open.  In doing so each spark will erode a tiny part of the contact material and the contacts will quickly deteriorate.  In the 1930s when SU designed our 'Type L' pump they originally used a second winding of resistance wire wound over the main coil to damp the stored energy.  This wasn't a particularly effective spark suppressor.  Later they tried a capacitor, then a diode which rendered the pump polarity sensitive and finally a voltage dependant resistor.  None of these devices work well.  Burlen Fuel Systems, who now own the SU name, finally stole my application of a Transil which is a very effective, non-polarity sensitive, arc suppressor which significantly increases the life of the contacts. In the ignition coil stored energy is used to convert the 12 volt battery voltage to around 500V, which is further increased by the turns ratio of the coil to around 20,000 volts to supply each plugs in turn via the rotor arm.  The capacitor in the ignition circuit essentially slows the rise of the ignition voltage whilst the points open, so that once they are open sufficiently wide they cannot be bridged by a spark.  A Transil in this application would prevent the production of the necessary high voltage as it would absorb all of the energy store in the coil at the end of the dwell period and there would be no spark.  Similarly if the capacitor is defective all of the stored energy in the coil will be dissipated in an arc across the points the instant they open. Eric Worpe, of this list has studied the ignition capacitor in great detail.  If your capacitor has LUCAS stamped on it, and it is a genuine Lucas part, it is probably 50 years old now and beyond its useful life.  If it  is a modern repro with LUCAS stamped on it it is probably a poor quality, unreliable component from China.  Eric has sourced a modern capacitor that will significantly enhance the reliability of your ignition circuit. I hope this helps Regards Peter

On Tue, 19 Jun 2018 at 20:10, Graham graham47tc@btinternet.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote: [u][/u]   Carrying on from the discussion, what is the difference between a transil and a capacitor? Can a larger transil be used in the distributor in place of a capacitor? If so, it could make electronic ignition unneccessary. I have no idea, but a few of you out there may be able to enlighten me. Graham TC3107 Buckingham Sent from my iPad

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[RICHARD HOWELL]

I have a Boyer Branden inductive discharge unit wired to the Distributor . It does away with the Capacitor , stops the points from burning and a small light flashes as the spark flashes  I suspect I am cheating but seems really good . Perhaps as part of this discussion somebody could tell me how it works Thanks Richard Howell TC 1575 Sent from my iPad

On 20 Jun 2018, at 15:03, Joe Curto joecurto@aol.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote:

  Here in USA a fellow well versed in T series cars  in New Hampshire who  has sourced a manufacturer of ignition Capacitors and has made them to spec and improving quality , he also makes Vacuum advances for later Lucas distributors  He also does all Lucas and  T series distributor  rebuilding  . If any interest  let me know and I will pass on his info Joe Curto 718-762-7878 www.joecurto.com -----Original Message----- From: Peter Cole pcoleuk@gmail.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> To: Graham graham47tc@btinternet.com> Cc: MG-TABC List mg-tabc@yahoogroups.com> Sent: Tue, Jun 19, 2018 4:17 pm Subject: Re: [mg-tabc] Electric fuel pumps   Graham, The simple answer is no!  In the case of the pump the stored energy in its coil is a problem..  Without some means of containing it it will cause a spark across the pump contact each time they open.  In doing so each spark will erode a tiny part of the contact material and the contacts will quickly deteriorate.  In the 1930s when SU designed our 'Type L' pump they originally used a second winding of resistance wire wound over the main coil to damp the stored energy.  This wasn't a particularly effective spark suppressor.  Later they tried a capacitor, then a diode which rendered the pump polarity sensitive and finally a voltage dependant resistor.  None of these devices work well.  Burlen Fuel Systems, who now own the SU name, finally stole my application of a Transil which is a very effective, non-polarity sensitive, arc suppressor which significantly increases the life of the contacts. In the ignition coil stored energy is used to convert the 12 volt battery voltage to around 500V, which is further increased by the turns ratio of the coil to around 20,000 volts to supply each plugs in turn via the rotor arm.  The capacitor in the ignition circuit essentially slows the rise of the ignition voltage whilst the points open, so that once they are open sufficiently wide they cannot be bridged by a spark.  A Transil in this application would prevent the production of the necessary high voltage as it would absorb all of the energy store in the coil at the end of the dwell period and there would be no spark.  Similarly if the capacitor is defective all of the stored energy in the coil will be dissipated in an arc across the points the instant they open. Eric Worpe, of this list has studied the ignition capacitor in great detail.  If your capacitor has LUCAS stamped on it, and it is a genuine Lucas part, it is probably 50 years old now and beyond its useful life.  If it  is a modern repro with LUCAS stamped on it it is probably a poor quality, unreliable component from China.  Eric has sourced a modern capacitor that will significantly enhance the reliability of your ignition circuit. I hope this helps Regards Peter On Tue, 19 Jun 2018 at 20:10, Graham graham47tc@btinternet.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote: [u][/u]   Carrying on from the discussion, what is the difference between a transil and a capacitor? Can a larger transil be used in the distributor in place of a capacitor? If so, it could make electronic ignition unneccessary. I have no idea, but a few of you out there may be able to enlighten me. Graham TC3107 Buckingham Sent from my iPad

[Tweed]

Hi Richard, I have a Boyer Bransden KIT00070 unit in TC 0632 and cannot praise it enough.  The previous owner of my previous TC, 2259, had fitted one to that and the points were still good after 40 odd thousand miles.  What makes them 'better' or longer lasting than some of the more conventional types available I don't know but they do.       There are a lot of dodgy condensers etc out there these days and if there is a way round of not having to take a gamble on ending up with one I wouldn't consider it 'cheating' .. it's using your loaf.   Boyer Bransden Electronics Ltd     Boyer Bransden Electronics Ltd

   

On Thursday, 21 June 2018, 23:20:48 BST, Richard Howell greenhaven20@yahoo.co.uk [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote:

  I have a Boyer Branden inductive discharge unit wired to the Distributor . It does away with the Capacitor , stops the points from burning and a small light flashes as the spark flashes  I suspect I am cheating but seems really good . Perhaps as part of this discussion somebody could tell me how it works Thanks Richard Howell TC 1575 Sent from my iPad On 20 Jun 2018, at 15:03, Joe Curto joecurto@aol.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote:   Here in USA a fellow well versed in T series cars  in New Hampshire who  has sourced a manufacturer of ignition Capacitors and has made them to spec and improving quality , he also makes Vacuum advances for later Lucas distributors  He also does all Lucas and  T series distributor  rebuilding  . If any interest  let me know and I will pass on his info Joe Curto 718-762-7878 www.joecurto.com -----Original Message----- From: Peter Cole pcoleuk@gmail.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> To: Graham graham47tc@btinternet.com> Cc: MG-TABC List mg-tabc@yahoogroups.com> Sent: Tue, Jun 19, 2018 4:17 pm Subject: Re: [mg-tabc] Electric fuel pumps   Graham, The simple answer is no!  In the case of the pump the stored energy in its coil is a problem..  Without some means of containing it it will cause a spark across the pump contact each time they open.  In doing so each spark will erode a tiny part of the contact material and the contacts will quickly deteriorate.  In the 1930s when SU designed our 'Type L' pump they originally used a second winding of resistance wire wound over the main coil to damp the stored energy.  This wasn't a particularly effective spark suppressor.  Later they tried a capacitor, then a diode which rendered the pump polarity sensitive and finally a voltage dependant resistor.  None of these devices work well.  Burlen Fuel Systems, who now own the SU name, finally stole my application of a Transil which is a very effective, non-polarity sensitive, arc suppressor which significantly increases the life of the contacts. In the ignition coil stored energy is used to convert the 12 volt battery voltage to around 500V, which is further increased by the turns ratio of the coil to around 20,000 volts to supply each plugs in turn via the rotor arm.  The capacitor in the ignition circuit essentially slows the rise of the ignition voltage whilst the points open, so that once they are open sufficiently wide they cannot be bridged by a spark.  A Transil in this application would prevent the production of the necessary high voltage as it would absorb all of the energy store in the coil at the end of the dwell period and there would be no spark.  Similarly if the capacitor is defective all of the stored energy in the coil will be dissipated in an arc across the points the instant they open. Eric Worpe, of this list has studied the ignition capacitor in great detail.  If your capacitor has LUCAS stamped on it, and it is a genuine Lucas part, it is probably 50 years old now and beyond its useful life.  If it  is a modern repro with LUCAS stamped on it it is probably a poor quality, unreliable component from China.  Eric has sourced a modern capacitor that will significantly enhance the reliability of your ignition circuit. I hope this helps Regards Peter On Tue, 19 Jun 2018 at 20:10, Graham graham47tc@btinternet.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote: [u][/u]   Carrying on from the discussion, what is the difference between a transil and a capacitor? Can a larger transil be used in the distributor in place of a capacitor? If so, it could make electronic ignition unneccessary. I have no idea, but a few of you out there may be able to enlighten me. Graham TC3107 Buckingham Sent from my iPad

[Michael Leckstein]

I purchased an M type from England over 10 years ago. It had and still has a ETI 200 ignition I have no idea how it works, but the unit is hidden under the dash on the firewall and has a toggle switch for electronic or regular ignition. The unit works with a regular set of points which never seem to wear out and the car starts and runs just great. These units appear on EBay UK every once in a while. Anybody familiar with them?

 

Mike

 

[b]From:[/b] mg-tabc@yahoogroups.com [mailto:mg-tabc@yahoogroups.com] [b]On Behalf Of [/b]Tweed lizandtweed@yahoo.co.uk [mg-tabc] [b]Sent:[/b] Friday, June 22, 2018 5:39 PM [b]To:[/b] Joe Curto; Richard Howell [b]Cc:[/b] pcoleuk@gmail.com; graham47tc@btinternet.com; mg-tabc@yahoogroups.com [b]Subject:[/b] Re: [mg-tabc] Electric fuel pumps

 

Hi Richard, I have a Boyer Bransden KIT00070 unit in TC 0632 and cannot praise it enough.  The previous owner of my previous TC, 2259, had fitted one to that and the points were still good after 40 odd thousand miles.  What makes them 'better' or longer lasting than some of the more conventional types available I don't know but they do.      

 

There are a lot of dodgy condensers etc out there these days and if there is a way round of not having to take a gamble on ending up with one I wouldn't consider it 'cheating' .. it's using your loaf.  

 

Boyer Bransden Electronics Ltd