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TR5/TR250 Windshield wiper motor

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David Stong

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Has anyone out there upgraded he windshield wiper motor from TR4/4A/250 to theTR6 unit? The wheel boxes, arms, etc. are all in good shape (I replaced them in the last rebuild), so there's no way I want to dig in under the dash again. Does the newer motor work OK in the older model, and can I just unhook the cable cam and attach it to the new unit?
 
Thanks, Tom. The link helps. Looks as if it is commonly done, so I'm assuming it will work for me. I'll let you know.

DAVE
 
I had the same plan, there are differences in the wiring and the switch that have to be figured out I think the mechanical hook up is the same, you need to fabricate anappropriate and sturdy new mounting point as well, doable, but not the easy swap I was hoping for.
 
I have a TR6 wiper motor on my TR4. But I was not the one to make the change. I do know that you will have a problem with the electrical hook up. The newer unit has a multi port plug. Try to get both sides of that plug if possible.
 
OK. I finally received the new motor,and I see what you mean about the difference in electrical hookups. It appears the TR6 switch has a connection to the voltage regulator, which the TR250 doesn't have. All other connections are the same, so I can just solder blade connections for them. But I would just not connect the voltage regulator, leaving one of the connections at the motor blank. Is that how yours was hooked up? Or do I need to buy a TR6 switch?
 
David,

You could use the 69-72 TR6 switch (same size) but the wiring is significantly different. Hopefully someone who has made the swap can explain how. The 'square' TR4A/250 DR3A wiper motor gets two speeds by using one or two (ie both) field windings. The TR6 'round' motor' has separate low and high speed brushes, and 'off' actually grounds out the low brush to ensure the blades park correctly. Check out Alan's great article in the Technical area.

Although the TR250 switch looks the same it is very different electrically. For whatever reason, the plastic used by Clear Hooters led to a high failure rate, although they probably didn't expect them to be in use 50 years later! Can your original motor be rebuilt?
 
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My TR4 uses the regular switch. One feature that is not hooked up is the stop. So I just turn the switch on and off until I get the wipers in the bottom or off position.
 
Thanks, TRopic6! I found Alan's article, but that appears to be related to TR4A and earlier. But it still explains a lot. My TR250 motor is a bit worn and under powered, so if I can get the new unit to function, I would prefer to use it. If not, I can rebuild it. But knowing that "theTR6 'round' motor' has separate low and high speed brushes, and 'off' actually grounds out the low brush to ensure the blades park correctly" is really helpful. RE: the switch, I've replaced it years ago with a new switch, and from what I can tell, TR6 and TR250 have the same part number. Also, years ago I installed an intermittent switch in the mix. Bottom line: I'm going to have to sit with and electrical meter and TR6 vs TR250 elec diagrams and plot it all out. Ouch. But hey, nothing better to do, right?

DAVE
 
Dave,

The TR4A and TR250 both originally had the same wiper motor (75568), but after 50 years someone may have swapped it out along the way. The TR250 wiper switch is unique and now pretty rare. Maybe you can use the plug part from the TR6 harness and wire it to a TR6 rocker switch. I bet someone has already done it and hopefully can advise of any hidden pitfalls.

Jeff
 
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