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TR2/3/3A Re: TR3 Bump stops and check straps.

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K

karls59tr

Obi Wan
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Re: TR3 Bump stops and check straps.

The bump stop is not located under the check strap but beside it. When the car hits a bump the the rubber bump stop contacts the underbody. When the car hits a pot hole the check strap prevents the axle from going down. The check strap is not bent over at an angle but stands straight up and down.
 
Re: TR3 Bump stops and check straps.

Are we talking about the same car?? On a TR3, there is no way the axle can come down against the strap, the strap doesn't run under the axle at all.

And as I said before, on my car, the axle hits the strap going up even if the strap isn't located over the buffer, well before the buffer hits the body. Which is a Good Thing since the buffer would quickly beat a hole in the flimsy sheet metal with the way I drive.

I remain convinced this is the correct configuration
attachment.php
 
Re: TR3 Bump stops and check straps.

Me too. Otherwise there would be no need for a rubber pad on the top of the bump stop -- and a big hit would be metal on metal (axle & strap).
 
Re: TR3 Bump stops and check straps.

Is anybody on this forum a member of the VTR? They could ask VTR technical consultant for their opinion on the correct location.:joyous:
 
Re: TR3 Bump stops and check straps.

The arrangement on a TR4 may provde a clue as it is less ambiguous. The strap is mounted to the top of the frame (instead of the side with a twist like the TR3) so there is no question of a bend. It is directly over the frame and directly over the rubber bump stop.

As you can see on mine (strap, bump stop & wires are original) it really works and is needed. Without that alignment the axle would slam into the metal strap on a big bump:

Bump%20Stop_zpsymcrhc2w.jpg


Right side of the car jacked up & wheel off - that is why the rubber buffer is resting on the frame.

Took the photo today as I was cleaning up after a long drive on graded roads along the border. Lots of dust and (apparently) lots of bump stop to strap contact on the washboards.
 
Re: TR3 Bump stops and check straps.

Well I guess what confused me was why the check strap on the TR3 would have to be bent over to serve it's function? I was thinking why didn't they mount the strap on top of the frame? So it seems that Triumph went ahead and did that on the Tr4. There are many TR3's here where the bump stop is not mounted under the strap and quite a few British car guys here telling me that that is normal? I think there is a picture of Chef Tush's rear axle on one of his viideos and it appears to me that the check straps are bent way over. Is that correct?
 
Re: TR3 Bump stops and check straps.

First, I totally agree with Randall as to the positioning of the strap. I say that with the experience of restoring two TR4's and one TR3. Out of those three cars one did have the straps almost vertical, in which case it would not function as needed. The other two cars had the straps bent properly.

George your picture of your TR4--What is the commission number? I have experience with three TR4's of commission numbers below 21000 and they were all like the TR3. None of them were like yours. Is yours a TR4A with solid axle?
That must have been a very rough ride you took to show that much use on those straps.
Charley
 
Re: TR3 Bump stops and check straps.

My TR4 is CT36536 - a September 1964 build date so a fairly late one. I don't think I have ever noted a production change for that part but it would seem to have happened somewhere along the way. I seem to recall there were other (minor) changes somewhere in the late 20000s (a spring spacer for one).

Yeah, the road was rough in spots and very dusty.

John%20Slaughter_zpsm0oj413h.jpg
 
Re: TR3 Bump stops and check straps.

I did notice the spring spacer, which made me jump to the TR4A guess. I am not aware of the change date for the rear spring. Just another subtle change.
Charley
 
Re: TR3 Bump stops and check straps.

I positioned my axle buffers in the Center of the frame as it seemed to make more sence to me, plus I have three tr3's that have the same arrangement. I have seen some that positioned the buffers more towards the outside of the frame rails.
Regardless, I positioned my straps in a fashion so that if the axle does ride up, it will contact the buffer and not the sheet metal of the car.

Cheers
Tush
 
Re: TR3 Bump stops and check straps.

A quick peek at the TR4 SPC shows the strap change at the same time as the blocks were added, CT23383.
 
Re: TR3 Bump stops and check straps.

My apologies Tush. I must have been looking at a different picture when I made my comment about the check straps being bent over on your 3. I viewed your rear axle video and it appears that that is not the case. In fact I believe where you have the rubber buffers and straps mounted is the correct location.
Karl
 
Re: TR3 Bump stops and check straps.

Having had the pleasure of "body working" 2 frames, I would recommend placing the bumper closer to the outside of the frame rather than the center. The frame is only 16 gage steel, so continually wacking it it the middle could eventually dent it. Not a big deal structurally...but something to consider.
 
Re: TR3 Bump stops and check straps.

I have been straitening those straps for years. I think this time, I will leave these straps bent and move the bumper to the outside.
 
Re: TR3 Bump stops and check straps.

TR3driver said:
Are we talking about the same car?? On a TR3, there is no way the axle can come down against the strap, the strap doesn't run under the axle at all.

And as I said before, on my car, the axle hits the strap going up even if the strap isn't located over the buffer, well before the buffer hits the body. Which is a Good Thing since the buffer would quickly beat a hole in the flimsy sheet metal with the way I drive.

I remain convinced this is the correct configuration
attachment.php
Click to expand...
Well I did get the part about the axle coming down on the strap wrong but I still believe the original setup was with the buffer beside and inboard of the check strap.
 
Re: TR3 Bump stops and check straps.

So, what do you think the strap is for, if the axle never touches it?? Some engineer was just bored and decided a strap looked good there?
 
Re: TR3 Bump stops and check straps.

Randall It turns out you were right all along. My apologies. I contacted Bill Redinger at VTR and he confirms the orientation you describe. There are a lot of TR3's I have seen where the buffers are located beside and inboard so it could be a case of previous owners not mounting them correctly when replaced. Keep up the good work supplying the forum with the correct info.:eagerness:
 
Re: TR3 Bump stops and check straps.

Something I learned about the buffers on this rebuild. When I temporally remove the buffer and let the axle go up to and rest on the frame, the access for the shock link bolt is much better.
 
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