Upper rear wishbone arm assembly ( sided "L" and "R" )

[martin cregan]

Hello again, I've searched the forum for the above and can't find a reference but apologies if I've missed it.

 

I am stripping my front suspension and have found the "R" and "L" stampings on the upper rear wishbone arms. My understanding is that when referring to the right and left of our cars , right means Offside and left means nearside.

 

If this is the case should I expect to find the "L" stamp on the uppermost of the nearside upper rear wishbone arm and "R" on the uppermost on the offside suspension ?

 

My reference book states that the front upper wishbone arms are interchangeable but not the rear arms. I think my car's rear upper wishbone arms have been mixed up at some time as the nearside assembly shows "R" uppermost and on the nearside shows "L" uppermost on the offside.

 

I hope I have made the above clear

 

thanks

 

Martin

[ianc]

Offside and Nearside are terms to be avoided as they can be construed differently on the Continent, in the USA and in many other countries.

Left and Right are unambiguous - one sits in the driver's seat, facing forwards, and Left is Left and Right is Right.

 

I'll leave someone else to pronounce on the meaning of the L and R markings on the wishbone arms.

 

Ian Cornish

[martin cregan]

Thanks for clearing that point up Ian, I'll refer to right and Left from now on.

 

Still can't find out why my upper rear wishbone arms are stamped both "R" and "L"

 

Martin

[peejay4A]

As I remember it if the L or R is uppermost, that's the side it goes on.

[BlueTR3A-5EKT]

This is a LH assembly for my money.

 

 

http://www.ebay.co.uk/itm/Triumph-TR6-left-n-s-front-top-suspension-wishbone-assembly-good-used-as-photo-/361086411492

 

 

 

Peter W

[Lebro]

Agree with Peter, but surely the same parts can be assembled the other way round to make it RH ?

 

Bob.

[Drewmotty]

It's to make sure that the short arms are on the rear. It's possible (on a TR4) to assemble the whole front suspension backwards which would reverse the castor angle but then the L would show on the right side and vice versa. I guess that they could have marked them "rear" or just credited motor mechanics with a bit of common sense.

[martin cregan]

Thanks, I agree with Pete, that my first thought was the uppermost marking was "side" appropriate, and yes Bob, I also think they can be used on either side as they are marked both "L" on one side and "R" on the other.

 

The car shook a lot while driving before I took it apart , I'm trying to eliminate all possible causes. The upper fulcrum pin was pointing in the wrong direction on the left hand side aswell as a wrongly positioned upper rear wishbone arm.

 

Cheers

 

Martin

[peejay4A]

Are the trunnions on the correct sides?

[boxofbits]

As you look from the top you want the arm with the most angle to be on the front. This will push back the upright toward the rear to give you castor in the upright. I would assume L means left of car.

 

Pete- I have tried to establish which side the trunnions go on but no one seems to know. Obviously they are left/right thread to suit the upright.

[peejay4A]

Iirc on the 4A both trunnions are threaded the same but they should be marked L and R to ensure the proper castor.

 

Edit. No they're not. See below...

Edited July 30, 2016 by peejay4A

[BlueTR3A-5EKT]

TR4A-250-5-6 trunions are threaded LH and RH.

 

TR2-3-3A-4 are all RH threaded ( and a smaller diameter than the later car ones.)

Edited July 30, 2016 by BlueTR3A-5EKT

[peejay4A]

Typical of me. I knew that 4 and 4A were different. D'OH!

 

Just make sure that the top of the vertical link is toward the rear of the car with respect to the bottom. On both sides of the car. I wonder if you have the same VL/trunnions on both sides.

Edited July 30, 2016 by peejay4A

[martin cregan]

Thanks for the advice, especially now about the about the trunnions.

 

I have just tried to fit a new right trunnion to the right vertical link and it wont fit, however the left trunnion will and vice - versa.

 

How could the car have driven in this condition, I bought the car with an MOT, could this be why there was so much vibration at 40 mph ?

 

Martin

[peejay4A]

If the castor is all to pot I'd think that anything could happen.

[BlueTR3A-5EKT]

Sorry Pete, I came across a bit short in my response about trunion threads.

 

Martin -

OK I have now touched a used TR4A-6 LH V. post and trunion and they are LH threaded, so the RH must be RH threaded, but I think you have worked this out with the replacement trunions.

 

Martin, Do I understand from your post that you have 2 lh V posts on your car? That would explain the curious handling.

 

I have had a scrabble through my TR suspension boxes and the only TR4A-6 V post I have is a reasonable condition but a bit rusty LH one that is missing its stub axle.

 

Did find a TR4 half shaft though - anyone need a spare?, plus lots of assorted NOS suspension bushes for TR2-6. no trunion bolts for TR4A-6 though.

 

Cheers

Peter W

[martin cregan]

Thanks Peter, but it appears that I have a left and right VL but they were fitted to the wrong sides on the car.

 

I've now separated all the components to their respective sides and I will start reassembling.

 

Any tips on getting a new stub axle into the VL, its obviously tight but I can't seem to get it flush where it's bolted to the VL, it looks to be about 1/16th inch short.

 

I thought tightening the bolt to torque would pull it flush but it hasn't moved, maybe a bit of heat to the VL ?

 

Martin

[TR NIALL]

Put the Stub Axle in the Freezer Overnight and Heat the VL.

[martin cregan]

Thanks Niall

[Drewmotty]

TR4 vertical links are not handed (same component both sides). The castor is introduced by the trunnions which are handed. You should selectively fit the he trunnions to the vertical links to give the best fit/least slop ( best done dry)and then grease and fit the matched pairs to the relevant sides as dictated by the trunnions.

If the 3 degree castor is not obvious check that zero castor TR3 trunnions have not been fitted in error.

If you need a big hammer or a bar to get things to fit then look again because something will be wrong.

Have fun.

Andrew W

[martin cregan]

Cheers Andrew, My car is a 4A and I have now established where the mixed up suspension parts go .

 

It was really useful talking on this forum as I had carefully separated and photographed the suspension units as they came off the chassis . It was only following correspondence on this site that I realised that several of my suspension arms were the wrong way around or miss-sided.

 

It's proving to be a steep learning curve and a proper challenge but it's good to know there is help/advice at hand

 

thanks again to all who take the time to contribute

 

Martin

[Drewmotty]

Glad that you're on the right track Martin

It will be useful if you could add your car model and a location to your profile. That way you can be sure of getting relavent information and locals are often able to help out.

[RogerH]

Hi Martin,

regarding the stub axle - should the axle be flush (as mentioned in your previous post).

A small gap would be necessary in order that the nut tightens down and not bottom on the stubby shoulder.

 

If it is not in far enough then you will see that when you assemble the bearings.

 

Roger