graycow Posted June 8, 2014 Report Share Posted June 8, 2014 I have looked through the previous threads and can't see an answer to this, so perhaps someone can put me right. As I understand the wiper racks are the same on pretty much all models, but it looks like when fitting a TR6 motor to an earlier car changing the wheelboxes is also suggested. Is this essential? Is there anything to stop me fitting a TR6 motor to a TR4 rack/wheelbox set up? Does it affect the sweep angle significantly or is there some other subtlety that I have missed that means you have to change the wheelboxes? Graham Quote Link to post Share on other sites
EdwinTiben Posted June 8, 2014 Report Share Posted June 8, 2014 I dont think changing wheelboxes is needed, if a different angle is needed, you can change the wheel for different degrees. Before AlanT upgraded my crt wiper, i used a tr6 wiper with the rest original. I changed the drive gear to 90 degrees. http://www.s-v-c.co.uk/product/14w-wiper-drive-gear/returns/ Quote Link to post Share on other sites
AlanT Posted June 8, 2014 Report Share Posted June 8, 2014 See thats a problem Edwin. You used a 90 degree wheel on a TR2 which does 130 degrees. A 4/4A/5 does 120 degrees. So you'd need an 80 degree wheel. I may be wrong but I don't think they made these. The standard TR6 wheel is 115 degrees. So I think you need TR6 wheel-boxes to match and then you can use a standard wheel. Can I ask why you want to fit a TR6 motor? Of course they are a bit stonger. Quote Link to post Share on other sites
MikeF Posted June 8, 2014 Report Share Posted June 8, 2014 I researched this when I had to replace my 4 wiper motor. The wheelboxes from the 6 are a form fit function replacement for the 4s, are much better designed and are easier to fit. The cable is also the same. Mike Quote Link to post Share on other sites
EdwinTiben Posted June 9, 2014 Report Share Posted June 9, 2014 See Thats why you have to hand over some if the works to the specialists... (null) Quote Link to post Share on other sites
graycow Posted June 9, 2014 Author Report Share Posted June 9, 2014 Can I ask why you want to fit a TR6 motor? Of course they are a bit stonger. The reason was basically to get a faster, two speed (and stronger) motor. Reading between the lines it looks like if I don't change the wheel or wheelboxes, but fit a TR6 motor, I will have too much sweep? I think I may have to change the wheelboxes anyway as I have a sweep of about 70 deg at the moment!! I may try the 180 deg rotate trick first to see if that helps. Graham Quote Link to post Share on other sites
AlanT Posted June 9, 2014 Report Share Posted June 9, 2014 (edited) Fit a new rack first, then turn the boxes. You can do this work easily in an afternoon. Fitting the wheel-boxes is really hard. Its not even easy if you take the whole dash out. Its just the amoun of access that you don't have thats the problem. Check that you do in fact have a 120 gear in the motor. Lots of these have been messed about and have wrong wheels. i've got two-speed DR3A motors if you need. Edited June 9, 2014 by AlanT Quote Link to post Share on other sites
MikeF Posted June 9, 2014 Report Share Posted June 9, 2014 You don't need to take the dash out. The workshop manual spells it out: you do need to remove passenger side glove box, the demist pipes both sides and the speedo + tachometer. Then you need room each side of car to dive under the dash board face up with your bum hanging out the side of the car and have some good light and some dimensionless spanners, you know the story. Turning the rack didn't do it for me as it had already been turned. I resisted the temptation to fix the old wheel boxes which are the same as side screen cars with their much smaller arms and so overworked on Michelotti bigger screen, and probably just as worn as rack for same reasons and replaced them with the 6 parts. I work on the premise there are some parts I never want to see again and these definitely fall into that category Mike Quote Link to post Share on other sites
mleadbeater Posted June 14, 2014 Report Share Posted June 14, 2014 Hi, if you need to adjust the sweep angle, you can move the position of the crank pin on the pinion plate, the pin can be re-brazed ( after dismantling of course) nearer or further from the centre as required to reduce/increase the stroke. You can work out the required off-set from the centre by measuring the rack stroke as is and then dividing the required increase/decrease by two to determine the amount you need to move the pin. ( hope this makes sense) I have done this on several cars over the years, including my current TR2 rebuild. Hope this helps Mike Quote Link to post Share on other sites
AlanT Posted June 16, 2014 Report Share Posted June 16, 2014 When I move my crank-pins I'm going to MIG them place using this jig: https://www.flickr.com/photos/90670218@N04/14202154441/ Quote Link to post Share on other sites
mleadbeater Posted June 19, 2014 Report Share Posted June 19, 2014 Jig looks good, but would'nt trust my might welding. Mike Quote Link to post Share on other sites
AlanT Posted June 19, 2014 Report Share Posted June 19, 2014 There will be a hole through the wheel disc in the right place and the bottom face of the crank-pin poking through it. This is a pretty easy kind if MIG weld. Quote Link to post Share on other sites
BlueTR3A-5EKT Posted June 19, 2014 Report Share Posted June 19, 2014 Tr4/5 wiper wheel boxes have fewer teeth on the drive gear that the rack drives than the TR 6. So the sweep will change unless you match the motor and drive gear to the wheel box. Quote Link to post Share on other sites
BlueTR3A-5EKT Posted June 19, 2014 Report Share Posted June 19, 2014 (edited) When I move my crank-pins I'm going to MIG them place using this jig: https://www.flickr.com/photos/90670218@N04/14202154441/ Give a man a mill and he is amused for hours....... Simple and sensible tooling to attach the crank pin. Cheers Peter W Edited June 19, 2014 by BlueTR3A-5EKT Quote Link to post Share on other sites
AlanT Posted June 20, 2014 Report Share Posted June 20, 2014 This is 2in thick steel, about 2.5in in diameter. I cut it off a piece 6in long with a hand-saw. Quote Link to post Share on other sites
Horse Posted July 3, 2014 Report Share Posted July 3, 2014 I may be a bit late with this comment but some may find it useful. My 4A's wipers were very sluggish and occasionally stopped altogether. In going through a series of checks and fixes to see if I could improve matters, I found that there was excessive end float with the wiper spindles that was allowing the drive wire to come partially out of engagement with the wiper shaft wheel, so increasing the friction in the wheel box. The spiral on the wire exacerbates this. The back of the wheel box has a "V" shaped tongue in the centre for adjusting the shaft end float by bending this in or out. One still has to gain access to the wheel box to do this, but having made the adjustment to remove virtually all of the end float my wipers are now a lot better and are no longer prone to stopping. And it is easily done seated in the driver's or passenger seat once the glove locker and speedometer and tacho have been removed. Quote Link to post Share on other sites
AlanT Posted July 3, 2014 Report Share Posted July 3, 2014 You are right. I can remember doing this with mine when I had them out. I'd forgotten all about it. Quote Link to post Share on other sites
TRnorm Posted August 31, 2014 Report Share Posted August 31, 2014 I think I'm correct in drawing from this series of posts that if I have nothing in the way of wiper gear (as my TR4 currently has) then I can simply fit the TR6 Motor, TR6 Drive and TR6 Wheelboxes. Is that a correct deduction? Thanks Norman Quote Link to post Share on other sites
stuart Posted August 31, 2014 Report Share Posted August 31, 2014 I think I'm correct in drawing from this series of posts that if I have nothing in the way of wiper gear (as my TR4 currently has) then I can simply fit the TR6 Motor, TR6 Drive and TR6 Wheelboxes. Is that a correct deduction? Thanks Norman Pretty much though you will have to make up a different mount for the motor, not over difficult as its only a bracket on top of the footwell. You will need the clamp and rubber pad for the motor as well and a small change in the wiring to run the two speeds. It is a standard uprate for the rally boys. Stuart. Quote Link to post Share on other sites
TRnorm Posted August 31, 2014 Report Share Posted August 31, 2014 Brilliant Stuart - very many thanks! Norman Quote Link to post Share on other sites
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