| Author | Message | ||
     John Beech Grand Master Username: jbeech Post Number: 411 Registered: 10-2016 |
Yesterday I experienced a FTP (Failure To Proceed - the term still gives me a giggle). Anyway, the engine turned over just fine but wouldn't fire. Removed the coil wire and no spark - until - switch-off whereupon it would spark once. My suspicion is the recently installed Pertronix electronic module has failed . . . and while this sucks, it couldn't have happened in a more convenient location because I had just moved her from one bay of the garage to another the other day and when I went to start the engine to move her back yesterday, she wouldn't start. Thus, I was in the shop with tools at hand versus being stuck on the side of the road. Could have been a lot worse!  - Pertronix electronic module installed in SRX6816 Anyway, removing the Pertronix and reinstalling the dual points saw Tootsie immediately firing with the first turn of the key - as usual.  - The points on SRX6816 gapped to 0.014"-0.016" per the manual, page M10 Next, I'll contact Pertronix and see if they will replace this under warranty, or whether I have farted away $200. Regardless, I am a bit disappointed. Maybe this will teach me about fixing what ain't broke! Especially because I drive all of 2000-3000 miles per year so maintenance wouldn't be onerous no matter what. By the way, the electrical system manual (page M10 manual M) indicates Tootsie's distributor should be fitted with vacuum advance. Thing is, Tootsie doesn't have the vacuum canister and likakge and thus, she appears to be mechanical advance, only. Are there parts missing, or is this correct?  - Vacuum advance is MIA on this Lucas 20D8 dual point distributor. -- John, color me perplexed. | ||
| Geoff Wootton Grand Master Username: dounraey Post Number: 1743 Registered: 5-2012 |
Hi John I had the same problem with my Powerspark unit and reverted back to points. I have since been running the car this way (although I have a new Powerspark ready to fit). With a similar annual mileage to you I am coming to the opinion it is better to run on points. The big advantage is points give plenty of forewarning of failure viz rough running of the engine. Electronic units most often just suddenly stop working, leaving you stranded. Have you refitted the 9v coil and ballast resister? I carried on using the 12v coil/no ballast resister setup with the mind to fit new Powerspark unit once I'd blown up the points. The thing is, two years on and the points are still ok. My car, a 74 SY1 (SRX18501) does not have vacuum advance. The chassis number booklet lists vacuum advance as added in June 1976 from chassis number 22572. Geoff | ||
| Geoff Wootton Grand Master Username: dounraey Post Number: 1744 Registered: 5-2012 |
I've just realized yours is the twin point model. The added difficulty in setting them up may be a good reason to go back to an electronic unit. I know Hubert fitted a Powerspark unit in place of his twin points for this very reason and has never looked back. My car has the single point distributor. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 1423 Registered: 9-2004 |
When the contacts are set up correctly and dwell set to allow for shaft movement the engine will run sweet. Triumph Stag and the Daimler Dart run well on the twin contact set up. In most cases one will get home with contacts, any failings are rare, use a radio suppressor etc in place of a condenser to get you home. Maybe the failing was causing your engine misfire all along. | ||
| ross kowalski Grand Master Username: cdfpw Post Number: 493 Registered: 11-2015 |
John, Nice photos. In defense of solid state point replacements they are WAY better when running super hot coils or working with uber high RPMs. Not that a RR has either! | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 1426 Registered: 9-2004 |
Progress over the years by OMEs is outstanding in this department. Not so IMO with aftermarket fitment. Seen to many failures that make repairs almost impossible to get the vehicles up and running in a short time, with standard OME parts you know what is on the car and can in most cases be readily obtained. | ||
| John G. Frequent User Username: john116 Post Number: 58 Registered: 4-2012 |
I've had multiple after market electronic ignition parts fail to the point where I've removed them all and gone back to points on all my cars that had points originally. Much more reliable it seems. | ||
| ross kowalski Grand Master Username: cdfpw Post Number: 494 Registered: 11-2015 |
Patrick L, I would replace an aging Lucas electronic ignition with points without hesitation. Of course, I'd also remove one set of points from that dual point unit as well. I wouldn't recommend a point retrofit for every owner / car and is completely because I maintain my own vehicles. | ||
| John Beech Grand Master Username: jbeech Post Number: 412 Registered: 10-2016 |
I'm uncertain regarding what's tricky about setting dual points. Would someone please explain? Meanwhile, I am buffaloed regarding the manual (M - Electrical System) and why on page M10 it shows the dual-point distributor and mentions this as being for cars prior to #8742 (Tootsie is SRX6816) because it shows the vacuum advance unit on the distributor. Similarly, it shows the single point distributor (35D8), and once again shows there to be a vacuum unit. Basically, there is no instance/description of any distributors 'not' being fitted with a vacuum unit. Beyond a vacuum unit, what am I missing? Last thing. I contacted Martin Jay (Distributor Doctor) about purchasing one of his red rotor buttons plus a new distributor cap. I mentioned the issue about the missing vacuum advance and he requested a serial number for the distributor. I've no clue where the number is and while I'll remove the distributor if needs be, if someone can guide me regarding its location, perhaps I can spy the number with the inspection camera, instead. This, because my back's killing me right now and thus, I don't want to even 'try' looking for it until I know where I need to look. Thoughts? | ||
| Geoff Wootton Grand Master Username: dounraey Post Number: 1745 Registered: 5-2012 |
Hi John I have no idea why the manual, section M, shows a distributor with the vacuum unit. One can only guess at these things. However the parts manual shows a distributor without the vacuum advance.  The picture below is an enlargement of the bottom right of the above diagram to show the serial numbers it applies to:  This final pic shows the position of the model and serial numbers on my car. However, this is for a later distributor but since both are made by Lucas they may have used the same site for the numbers. It's worth checking there first. The other thing to note is the numbers may be very faded and difficult to see. I took many pics and sharpened the images to finally get one that showed the numbers.  | ||
| John Beech Grand Master Username: jbeech Post Number: 413 Registered: 10-2016 |
Fantastic, Geoff, many thanks! | ||
| h_kelly Prolific User Username: h_kelly Post Number: 221 Registered: 3-2012 |
Hi Ross, you mentioned you would remove one set of points from that dual unit, can you enlightenment me how this can be done?. Can you keep the same distributor and simply replace a single set of points off a 35 D distributor ?. Many thanks | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 1430 Registered: 9-2004 |
The listing for the shadow distributor type for 1965-1959 is shown as Lucas 20D8. This unit is shown to have VAC advance. Total cent+vac is shown at 43-47 degrees. 1971 is all change on many types, no vac. | ||
| ross kowalski Grand Master Username: cdfpw Post Number: 499 Registered: 11-2015 |
H_kelly, I would remove the wire bridging between the two sets of points, remove the second set of points, and regap the remaining set of points to get the proper dwell. It's possible, though highly unlikely, the point cam lobe profile would prevent this Dual points were added to make points last longer with hot coils and high rpm, and arguably improved reliability. A Royce does not need two sets of points. Patrick L often makes a very correct point on ideas like this, if you muck about and make your car a one off there will be a learning curve for mechanics and future custodians of the car. So, caution there. I do my own work and thoroughly enjoy simple elegant engineering. Would I have done this? Ask me where my weakener system is. QED | ||
| h_kelly Prolific User Username: h_kelly Post Number: 222 Registered: 3-2012 |
Thanks for getting back to me Ross, I think I'll leave well enough alone for now, it sounds a little beyond my capabilities. Appreciate your detailed insight. Many thanks Hk | ||
| John Beech Grand Master Username: jbeech Post Number: 417 Registered: 10-2016 |
Patrick, a 20D8 for 1965-1969 and they're fitted with vacuum advance, eh? Guess I'm going to have to get a number off this distributor to resolve this mystery. I really cannot imagine anyone removing the vacuum advance. I suspect Distributor Doctor will be of great help. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 1432 Registered: 9-2004 |
John, something tells me that the fitment of some after market electronic systems had the vac advance removed! Some data for your car 65-69:   | ||
| John Beech Grand Master Username: jbeech Post Number: 418 Registered: 10-2016 |
Thanks for the data Patrick. What's the source? Anyway, I presume the column that's been scratched out is for some other model. Anyway, it sure looks like I'm going to need to source some bits to return my distributor to proper operation. Bet the added advance will perk things up a little, too. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 1441 Registered: 9-2004 |
John the source of technical data is from SUN technical data manuals. USA company and owned to-day by Snap-on. IMO the best. Well worn but still of use with other later year books up to the Snap-on data scanners and the like. Ignition timing I would say set up with V Power gas, fine tune on a hot motor up hill at low torque for to eliminate any pinking or pinging in USA. All data is with the cooperation and authenticated by the manufactures with new or amended data that IMO makes some of the Shadows workshop manual data incorrect.   | ||
| John Beech Grand Master Username: jbeech Post Number: 424 Registered: 10-2016 |
Patrick L, Fantastic, thank you. I have been snowed under with work matters and family visiting and thus, absent from here. On the flip side, the AC system in the new office within my building is finally connected and working - yippee! Sadly, this happens 3 months into a miserably hot summer but as the saying goes; better late than never. Anyway, as soon as I catch up I will turn my attention back to Tootsie (but fear this may take us to Christmas). Is what it is. -- John, who is loving life with grandsons and will miss them dearly when they depart on Friday |
