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TR2/3/3A Windscreen Wiper Stroke TR3A

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Quelch

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Does anyone know if there is any way to adjust the stroke of the windscreen wipers on a TR3A. On mine the stroke is too long, resulting in the wipers going over the chrome of the windscreen surround.
Any suggestions would be appreciated.
 
Are you sure the wiper motor is the correct one. There is no adjustment. Motor turns a plastic gear that moves the cable a certain distance. Can't remember if a TR4 is bigger or not. Only adjustment is the wiper park.

Marv
 
Is it going over the chrome in only one direction?? Or both sides of the sweep?? If in only one direction, remove the wiper arms and re-locate. Also, the wipers have a "park" adjustment. It's the round dome with a wire coming out of it. Loosen the three screws, and you can rotate it to set the park position.

As far as over rotating in both directions, I don't know of any adjustment. Maybe the very early (TR2) motors had more sweep, but IIRC, they didn't have a park mechanism. Do you have the right length wiper blades on??
 
THanks, it's over rotating in the opposite direction from park, I'll try and adjust the park as you suggested. Is it on the motor itself?
 
I think that you have to re-orient the wiper arms on the spindles. At least that's what it sounds like. In other words, the wipers aren't going to the full down position. Is that correct?? Operate the wipers, then turn them off. If they stop before they get down, just take the arms off and position them on the spindles in the down position. If you have to adjust the down position a little after this, look for the round dome with the wire coming out of it on the wiper motor assembly. If you loosen the three screws holding it down, you can rotate it and adjust the park position.
 
Just to echo the above, the sweep distance is set by the big gear inside the motor. The gear should be stamped with the sweep angle. There were a variety of them made (same motor used on many different cars), so it is possible that someone has installed the wrong gear.

The park switch only controls at what point in the sweep the arms stop when you turn off the switch. It has no effect on how far (or where) the arms sweep while the switch is on.
 
I have played with the wipers on tr3s before, and I have never got them correct. They either go down too far and pass by the chrome bottom piece or the stop to soon before they get to the bottom of the glass. A guy once told me that they are not actually wipers, but cheap jewelry.
 
I had mine working pretty good on the 3A before it got wrecked. If you can't get the arms to stay on the spindles in just the right orientation, it may help to remove the rack and turn the spindles by a few teeth.

Another thing that made the wipers work much better IMO was to replace the solid blades with the flexible blades. (Came from a MGA, I think.) Then you can actually replace the inserts from time to time, by buying plastic replacements and cutting them to length.

But so far I haven't bothered doing anything with them on the "new" TR3. The motor is in pieces laying in the parts bin and I'm probably going to have to pull the wheelboxes back out to get them to turn freely as they should.
 
I still hold to the belief that the only purpose of the TR3 wipers is to pass the state inspection!

John
 
Thought I remembered this thread ... just had to find it! Trying to sort out the wipers on my 56 TR3 (no park mechanism). At the "park" side they are fine, but they run over the chrome as described by Quelch, and adjusting the arms on the spindle does not allow enough adjustment to correct this (they are attached with a barrel type compression nut). I was wondering if in fact they should be parking on the other side. Car is 56 LDH and I have wipers oriented so they point to left when sitting in driver's seat. Is that correct? Seems to me I've seen wipers parked facing to the right on pictures of some other cars. Comments and suggestions most welcome, although other than for passing safety check I don't think I will use them often. Cheers, Mike
 
" Also notice the dimple on the outside of the round cover (picture below). The dimple indicates the park position of crank pin. For LHD the cable needs to be fully extended to park the wiper arms on the left, so the dimple points toward the cable tube. For RHD the cable needs to be fully retracted to park the wiper arms on the right, so the dimple points away the cable tube. If you should choose to rel ocate the wiper motor to the opposite side of the car for convenience of servicing, the park position of the cable will be opposite. The above info obtained from this link https://mgaguru.com/mgtech/electric/et217.htm
 
Thanks. That is a great site for reference, unfortunately, my early TR3 has a non-park motor that does not have the round cover. Cheers, Mike

 
We've had some debate about that on another forum. I believe that, for the early TRs, the wipers were designed to come down parallel to the windshield frame on the RH side for LHD cars, and LH side for RHD cars. Of course with no automatic parking, you can leave them wherever you wish, but flat against the frame seems like the place to park them to me.

As I said before, there is no adjustment for sweep, except for changing parts. The sweep angle for a TR3 is given as 130 degrees, which you may be able to find marked somewhere on the big gear inside the motor. Or maybe the Lucas part number, which I think should be 738908.

Here's the diagram for the arm angle, from the Lucas 400e catalog. The LHD arms are P/N 742147, which is listed as 9.5" long with a 15 degree LH "crank" (angle).

untitled-3.jpg
 
Can you post a pic of your wiper motor so that I can tell what type you have?

I believe the correct one will be a DR3A with a 130 degree wheel. People often fit DR3A from other vehicles assuming they are all the same.
Mostly saloons use a 150 degree wheel. Its 120 degrees for a 4/4A and 115 for a TR6 BTW.

I recon these for UK TR guys and spare/correct parts are available over here.

Try this link for the original Lucas part-manuals:

https://www.vitessesteve.co.uk/LucasStuff/LucasStuff1.htm

With a bit of luck you will be able to find correct p/n for the motor and check it against yours.

Wear in the wire-rack that joins the motor to the wheel-boxes or wear in the wheel boxes will make it look like the motor over-sweeps.

It a good idea to take the wipers off and tape on two pointers made of drinking straws. This avoids nasty accidents to paint-work while you are messing with this.

Al.
 
Thanks Randall and Al for the input. Randall looks like big gear is 738908, but if you are right then I have wipers pointed in wrong direction at park. Do you recall where the other discussion took place? I did search several other forums before posting here. Al, motor is model CRT. Cheers, Mike



 
mgedit said:
Do you recall where the other discussion took place? I did search several other forums before posting here. Al, motor is model CRT. Cheers, Mike
Click to expand...
Hmm, seems like it was the TRA forum, but I can't find the thread. Likely it was thread drift from some other topic. At any rate, it caused me to look up the details in the Lucas master catalog, where I found the details about the wiper arms.

Alan, the CRT15 as Mike shows would be correct for TR3 up to roughly mid 1956 (TS12567, July 1956 according to Bill Piggott). The entire wiper system changed at that point, including the motor, motor location, mounting bracket, wiring, wheel boxes and arms. Later TR3 (like my late 56) used DR2 (unless they had the optional 2-speed wipers, apparently quite rare). I don't think the DR3A was introduced until the TR4.

View attachment 27406
 
Thanks Randall. Just had a look at the wiper arms with the information you provided and it seems I have the crank RH type (think 15 degrees, but could be 10 degrees ... hard to measure) as came with the car. Assume these arms are for parking on right side when looking from front of car (so on driver side of LHD car). To park on left side (passenger side for LHD car), I believe I would need the crank LH type arms. No way the RH type will park properly on passenger side. As set up now they park fine (although not quite parallel to chrome) but run over the chrome on the other end of the sweep. I think I can live with current setup (assuming I really never need to use the wipers), but would be nice to find some LH type arms to test fit those to see if those work better parking on other side.

My parts book list two different wipers depending on whether L.H.S. or R.H.S. (I assume this means right hand steering or left hand steering) up to serial number 12567.

Is this the other thread you were thinking about? https://triumphregister.lefora.com/2011/06/05/triumph-tr2-windscreen-wipers-parked-differently-f/

Cheers, Mike




 
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