jir Posted February 21, 2011 Report Share Posted February 21, 2011 My car, (63 TR4) has a wiper motor marked "DR3A 12V 75448B". It works as a single speed and no park function, but the wiper switch is two speed (Lucas original) and has also the two speed wiring loom. The motor case has three wires (green, white, brown) and only works if green is +12V and the others grounded both (?). The car has been converted to negative earth and alternator by a previous owner. Somewhere in the Net (The Triumph Experience - Triumphs List Archive) I found a thread about wiper motor DR3A as special option in the TR4. http://www.triumphexperience.com/archive/tr4_wiper_motor_equipment/509442 But this is the only reference about what seems to be an odd option. Has anybody, in the forum, a cue about that? Regards Quote Link to post Share on other sites
ianc Posted February 21, 2011 Report Share Posted February 21, 2011 According to Ian Gibson's article in TR Action 218 (April 2007): "the two-speed option for the TR4 was DR3A Part No. 75448 - the TR4A was fitted with the two-speed DR3A Part No. 75668 as standard fitment". The Green wire is the supply to the motor, as you have stated. To get Low Speed operation, both the White and the Brown must be grounded via the switch (as you have stated). To get High Speed operation, only ONE of those two should be grounded. However, I cannot tell you which it should be because your wire colours differ from the diagram which I have here! If you ground the wrong wire for any length of time, I am informed that you will cook the motor! I would suggest that you ground just one of the two for a very short time and see what happens - if the motor runs at high speed, that's fine. If it doesn't, try the other. Once you have decided which of the two has to be grounded in BOTH High and Low Speed and which has to be grounded solely in Low Speed, make sure that you connect to the switch correctly! You may need to use a multimeter on the switch to decide what happens in each of its 3 positions. I cannot say whether the switch sequence goes OFF-LOW-HIGH or OFF-HIGH-LOW. Mine is the former, but I have an entirely different motor (of a type not fitted to TRs) and a switch with 13 connectors. I have heard that some cars go to HIGH first - the latter sequence. Ian Cornish Quote Link to post Share on other sites
Ade-TR4 Posted February 22, 2011 Report Share Posted February 22, 2011 Hi I found it easy to think of the wiper switch like a headlight switch in terms of wiring. Position one - Side lights only/ Wiper speed fast. Position two - Side lights & main/ Wiper speed slow. You need to earth the casing to get the auto-park function too. Cheers Ade Quote Link to post Share on other sites
BlueTR3A-5EKT Posted February 23, 2011 Report Share Posted February 23, 2011 My car, (63 TR4) has a wiper motor marked "DR3A 12V 75448B". It works as a single speed and no park function, but the wiper switch is two speed (Lucas original) and has also the two speed wiring loom. The motor case has three wires (green, white, brown) and only works if green is +12V and the others grounded both (?). The car has been converted to negative earth and alternator by a previous owner. Somewhere in the Net (The Triumph Experience - Triumphs List Archive) I found a thread about wiper motor DR3A as special option in the TR4. http://www.triumphex...quipment/509442 But this is the only reference about what seems to be an odd option. Has anybody, in the forum, a cue about that? Regards I do not see what I would call a self park mechanism or switch in either of your photos. Ian is right on the wiring. Green is ignition controlled live feed and the other two go back to the switch and then to earth as selected. Connect both (white & brown) to earth and you get low speed. Connect only one and you get standard speed. Which one I also can not say as the colours do not match my diags. You need to earth the casing to get the self park to work. PM me if you want a complete Lucas 75568 2 speed wiper motor built with NOS parts from TR4A/250/5. Peter W Quote Link to post Share on other sites
jir Posted February 26, 2011 Author Report Share Posted February 26, 2011 Quick test today gives the following results. Green +12V white earthed ----- No action. Green +12V brown earthed ----- No action. Green +12V white & brown BOTH earthed ----- motor running, don't know if fast or slow (but maybe is fast). Earthing the casing doesn't help And there is not self park switch as I see in many pictures and spares catalogs. Next step: Open the casing and diagnose armature, brushes, wiring... Regards Jose I. Quote Link to post Share on other sites
johnny250 Posted February 27, 2011 Report Share Posted February 27, 2011 Quick test today gives the following results. Green +12V white earthed ----- No action. Green +12V brown earthed ----- No action. Green +12V white & brown BOTH earthed ----- motor running, don't know if fast or slow (but maybe is fast). Earthing the casing doesn't help And there is not self park switch as I see in many pictures and spares catalogs. Next step: Open the casing and diagnose armature, brushes, wiring... Regards Jose I. Or leave it fast and fit a simple wiper delay unit?? john Quote Link to post Share on other sites
Dazzer Posted February 27, 2011 Report Share Posted February 27, 2011 All the motors have a park mechanism, just take off the silver gear plate (as per your photo) there will (or should be) a brass/copper spring loaded contact which can sit in two positions. It might have broken its locater contact or be fitted incorrectly. Cheers Darren Quote Link to post Share on other sites
BlueTR3A-5EKT Posted February 27, 2011 Report Share Posted February 27, 2011 (edited) All the motors have a park mechanism, just take off the silver gear plate (as per your photo) there will (or should be) a brass/copper spring loaded contact which can sit in two positions. It might have broken its locater contact or be fitted incorrectly. Cheers Darren The photo shews the gearbox cover to be an all pressed in one aluminium thing not the two piece steel arrangement found on the more common type. The round steel part of the two piece arrangement with a wire attached being the adjustable parking switch. The last wiper motor of this style with an aluminium gearbox lid that I repaired was allegedly from an 'ex works Mini Cooper S', and that did not have self park either. The owner advised me that it enabled the wipers to be positioned wherever the occupants fancied - very Abingdon ...... Other parking devices include a screw and spring arrangement into the end of the gearbox next to the rack outlet. OR the reversing motor. The motor photographed has insufficient wires to be like the Jag/Rolls arrangement that reverses when the switch is set to 'park' and parks the wipers off the screen. Strip the motor and post some photos so we can do a repair by internet..... What was original on 4VC? or any other real works TR4 s. Peter W PS - CRT Type wiper motor from TR2/3 did not self park either. Edited February 27, 2011 by BlueTR3A-5EKT Quote Link to post Share on other sites
ianc Posted February 27, 2011 Report Share Posted February 27, 2011 4VC has a switch with 13 terminals; there are 5 wires from switch to motor and the motor additionally has an earth and a 12V feed. The motor is 2-speed, with the sequence OFF/LOW/HIGH on the switch. The motor reverses to park the blades at the bottom of the screen when the switch is moved from LOW to OFF. I seem to remember, Pete, that you told me this unit was probably used on a Jaguar. Ian Cornish Quote Link to post Share on other sites
stuart Posted February 27, 2011 Report Share Posted February 27, 2011 4VC has a switch with 13 terminals; there are 5 wires from switch to motor and the motor additionally has an earth and a 12V feed. The motor is 2-speed, with the sequence OFF/LOW/HIGH on the switch. The motor reverses to park the blades at the bottom of the screen when the switch is moved from LOW to OFF. I seem to remember, Pete, that you told me this unit was probably used on a Jaguar. Ian Cornish Jaguar MK2/S type I suspect. The wipers almost do a little dance backwards and forwards before parking. Stuart Quote Link to post Share on other sites
ianc Posted March 1, 2011 Report Share Posted March 1, 2011 Stuart, Yes, depending in which direction the wipers were travelling when I switch OFF, they can indeed do a little dance when heading for the park position at the bottom of the screen! Thanks for the information concerning the likely provenance - useful should the motor fail. Ian Cornish Quote Link to post Share on other sites
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