PaulAA Posted May 19, 2014 Report Share Posted May 19, 2014 Dear Sages The issue of lower wishbone failure has cropped up in a couple of recent threads and a swift search of the forum yielded references from those who had either knowledge or experience of the event, but nothing specific in the way of detail. I wondered if, for the benefit of the naive, inexperienced and blind amongst us (I score in all three categories, by the way), a few words, or even a gruesome picture, could be shared on what to look for and where, together with what precautions and preventions might be taken to avert disaster. Apologies if I have missed the relevant thread - a reprimand and link will be equally fine. Immense gratitude will ensue. Paul Quote Link to post Share on other sites
RogerH Posted May 19, 2014 Report Share Posted May 19, 2014 Hi Paul, have a look here http://www.tr-register.co.uk/forums/index.php?/topic/20708-lower-wishbone-bracket-collapse/?hl=%2Blower+%2Bwishbone+%2Bfailure It is for TR4/4A for the 6 chassis is similar. The lower wishbone bracket is held on with one stud. This can pull through/snap/ do odd things. Replacement with the double stud variety is recommended. Whilst worrying about the wishbones also look at the vertical link where it joins the trunnion - is it perfectly clean or are there traces of corrosion Roger Quote Link to post Share on other sites
stuart Posted May 19, 2014 Report Share Posted May 19, 2014 The lower front inner wishbone mounting boxes can also tear away from the chassis if they havent been re-enforced. There is a kit of 4 plates available from all the usual suspects to help prevent this. The later cars did have one extra plate added but earlier ones like 4a`s didnt. Stuart. Quote Link to post Share on other sites
stuart Posted May 19, 2014 Report Share Posted May 19, 2014 Hi Paul, have a look here http://www.tr-register.co.uk/forums/index.php?/topic/20708-lower-wishbone-bracket-collapse/?hl=%2Blower+%2Bwishbone+%2Bfailure It is for TR4/4A for the 6 chassis is similar. The lower wishbone bracket is held on with one stud. This can pull through/snap/ do odd things. Replacement with the double stud variety is recommended. Roger Only the 4a`s have the single bolt fixings TR5 on they were changed to 2 bolt by the factory. Stuart. Quote Link to post Share on other sites
stuart Posted May 19, 2014 Report Share Posted May 19, 2014 With thanks to TR4 Tony who has just reminded me that there is also an extra re-enforcing plate to fit inside the wishbone boxes the stop the studs pulling through if you use big sticky tyres and do throw the car about a bit. Part number 139580R. Though if you are also running a lot of neg camber you will need the longer stud version of the inner bracket available I believe from Revingtons. Stuart. Quote Link to post Share on other sites
PaulAA Posted May 19, 2014 Author Report Share Posted May 19, 2014 Deep gratitude, chaps. About to descend to the garage and look for repairs and/or cracks. A google search also yielded the following link to the forum - would this be the beast? With thanks to TR4 Tony who has just reminded me that there is also an extra re-enforcing plate to fit inside the wishbone boxes the stop the studs pulling through if you use big sticky tyres and do throw the car about a bit. Part number 139580R. Though if you are also running a lot of neg camber you will need the longer stud version of the inner bracket available I believe from Revingtons. Stuart. Hopefully not applicable, seeing as I am still some way short of the hooligan class. Paul Quote Link to post Share on other sites
Britishbest Posted March 24, 2017 Report Share Posted March 24, 2017 umph! Another bit (x4) needed, mine has single stud. Arse. Quote Link to post Share on other sites
RogerH Posted March 24, 2017 Report Share Posted March 24, 2017 You must change to the twin stud fixing. A single stud WILL fail. Roger Quote Link to post Share on other sites
Britishbest Posted March 24, 2017 Report Share Posted March 24, 2017 Roger thanks. It just occurred to me I can weld another bolt into what I have and there we go 2 stud mount. Quote Link to post Share on other sites
RogerH Posted March 24, 2017 Report Share Posted March 24, 2017 Make sure the head of the bolt that you weld in does not cause a problem. The normal ones in there have a flat head. Roger Quote Link to post Share on other sites
Britishbest Posted March 24, 2017 Report Share Posted March 24, 2017 Make sure the head of the bolt that you weld in does not cause a problem. The normal ones in there have a flat head. Roger Will do thanks. £80 clawed back, now allocated towards a chassis repair! Quote Link to post Share on other sites
Waldi Posted March 24, 2017 Report Share Posted March 24, 2017 Welding bolts is not a good idea, bolts typically are made or Cr-Mo material which can harden during welding resulting in cracks. It is not impossible, but better avoided, unless you know how. Regards, Waldi Quote Link to post Share on other sites
Blue cedar Posted March 24, 2017 Report Share Posted March 24, 2017 (The lower front inner wishbone mounting boxes can also tear away from the chassis if they havent been re-enforced. There is a kit of 4 plates available from all the usual suspects to help prevent this. The later cars did have one extra plate added but earlier ones like 4a`s didnt. Stuart.)........ Stuart is that why my 1970 6 has a single support plate on the lower wishbone mounts nearest the bulkhead ? Quote Link to post Share on other sites
stuart Posted March 24, 2017 Report Share Posted March 24, 2017 (The lower front inner wishbone mounting boxes can also tear away from the chassis if they havent been re-enforced. There is a kit of 4 plates available from all the usual suspects to help prevent this. The later cars did have one extra plate added but earlier ones like 4a`s didnt. Stuart. )........ Stuart is that why my 1970 6 has a single support plate on the lower wishbone mounts nearest the bulkhead ? It is, the available re-enforcing kit actually contains 3 plates for each side as it covers 4a as well, you will need to only use two of them. Be aware the front one on the rear box (thats the shorter of the 3 ) needs to be fitted at an angle forward to allow clearance for the inner wishbone mounting bolt. Stuart. Quote Link to post Share on other sites
Waldi Posted March 25, 2017 Report Share Posted March 25, 2017 I had to grind a radius on the back face of the thick plates to ensure the plates were properly seating against the existing brackets. So I recommend to verify this if you install them. Quote Link to post Share on other sites
RobinTR Posted March 25, 2017 Report Share Posted March 25, 2017 Are the thicker plates used just like oversized washers, or is it necessary to weld them to the original wishbone boxes? Stuart mentioned that some applications may need wishbone brackets with longer studs, so just how thick are these strengthening plates? Are they something which anyone could make up with a bit of plate, grinder and pillar drill? Quote Link to post Share on other sites
Britishbest Posted March 25, 2017 Report Share Posted March 25, 2017 All good advice, will look for the re inforcement kit and check on the bolt material.. Quote Link to post Share on other sites
HarveyCoppock Posted March 25, 2017 Report Share Posted March 25, 2017 Are the thicker plates used just like oversized washers, or is it necessary to weld them to the original wishbone boxes? Stuart mentioned that some applications may need wishbone brackets with longer studs, so just how thick are these strengthening plates? Are they something which anyone could make up with a bit of plate, grinder and pillar drill? They just slot neatly in at the back, same shape as the vertical plate. Don't think welding them would achieve much, they stop the nuts and washers pulling through. Think they were about 10 gauge, plated, but you could make them. I didn't need longer studs, but probably depends how many alignment shims you have in. Quote Link to post Share on other sites
stuart Posted March 27, 2017 Report Share Posted March 27, 2017 Are the thicker plates used just like oversized washers, or is it necessary to weld them to the original wishbone boxes? Stuart mentioned that some applications may need wishbone brackets with longer studs, so just how thick are these strengthening plates? Are they something which anyone could make up with a bit of plate, grinder and pillar drill? You will need the longer studded inner brackets to fit these if you have the usual 3 shims fitted. The plates do sometimes need the corners grinding off as the original welding around the inside of the box sometimes wont let them sit in flat. Stuart. Quote Link to post Share on other sites
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