brian-nz Posted December 9, 2013 Report Share Posted December 9, 2013 Hi All Had a moment yesterday when the left hand vertical link snapped inside the trunnion. Quite scary but fortunately only going about 30kph. The chassis being face planted on the road. I have taken the vertical link off and notice that the trunnion is extremely tight. Is this what caused the breakage. Should the trunnion pivot freely. It seemed they might have seized Regards Brian Quote Link to post Share on other sites
littlejim Posted December 9, 2013 Report Share Posted December 9, 2013 Suspect your heart rate equalled mine, when the front right wing nut came off the wheel , and ran up the road in front of me. Hope not too much got busted. Quote Link to post Share on other sites
TR 2100 Posted December 9, 2013 Report Share Posted December 9, 2013 I recall that in the very early days of TR2 development, this kind of problem was found - and corrected. Can't remember exactly what the mod was, but the trunnion MUST move freely. If the vertical link has been screwed in too tight, maybe to compensate for some wear, that could well lead to breakage of the vertical link. The new Moss vertical arm is manufactured slightly oversize to compensate for some wear, so caution is required when fitting these. Quote Link to post Share on other sites
RogerH Posted December 9, 2013 Report Share Posted December 9, 2013 Hi Brian, at the top of the threaded section there should be a seal. This stops water and muck getting in to the trunnion. After many years water does get in and can create corrosion. This will weaken the threaded section and the snap. Have you got a pic of the offending iten plus the crack face. Roger Quote Link to post Share on other sites
brian-nz Posted December 9, 2013 Author Report Share Posted December 9, 2013 Thanks Guys Looks like the trunnion has seized up which is likely cause of problem. Should be able to drill out the snapped part of the vertical link. Would not wanted to be doing any higher speed. Brian Quote Link to post Share on other sites
Don Elliott Posted December 9, 2013 Report Share Posted December 9, 2013 Was there any warning ? Did you find it stiff during turns for the past few hundred miles ? Quote Link to post Share on other sites
Peter Cobbold Posted December 9, 2013 Report Share Posted December 9, 2013 (edited) Hi Brian, at the top of the threaded section there should be a seal. This stops water and muck getting in to the trunnion. After many years water does get in and can create corrosion. This will weaken the threaded section and the snap. Have you got a pic of the offending iten plus the crack face. Roger Rod Ker in a Triumph World article described as common the corrosion-induced failure at the top of the thread above the seal ( IIRC) on Herald types. OK, so TRs are more substantial but.....as Roger says, check for rust. Edited December 9, 2013 by Peter Cobbold Quote Link to post Share on other sites
brian-nz Posted December 10, 2013 Author Report Share Posted December 10, 2013 Hi Don No there was no warning. The steering had been stiff but after adjusting the steering idler it seemed okay. The trunnion was new only two years old but car had been sitting for that 2 years while body work was being carried out. The vertical link however was not new and may have suffered from previous damage. Corrosion I don't think was a factor in this case. Brian Quote Link to post Share on other sites
ianc Posted December 10, 2013 Report Share Posted December 10, 2013 Be very careful when drilling out the remaining part of the vertical link as you must not damage the thread in the trunnion. Many years ago, I purchased a TR on which the steering got tighter and lock in one direction was being reduced. I dismantled the suspension but was unable to unscrew the vertical link from the trunnion, even after applying heat. As one's life depends on these items remaining together, I purchased both vertical link and trunnion. Regular lubrication of the trunnion/vertical link is VITAL. Whether you use oil or, as most of us do, moly grease (I use Castrol LM for everything), doesn't matter - it's lubricating regularly and frequently that matters. A messy job, but quite satisfying once it's done, and it gives one the opportunity to inspect for wear of suspension items, bearings and brake pads. Ian Cornish Quote Link to post Share on other sites
Alec Pringle Posted December 10, 2013 Report Share Posted December 10, 2013 Classic illustration of the importance of an annual MoT inspection. Any MoT tester worth his or her salt will check the suspension and steering of any classic carefully, a tester is accustomed to stiff trunnions and suchlike - and will note any concerns as 'advisories', even if they are not 'fail' items. The average classic car owner is simply not competent to assess the mechanical condition of his or her prized machine, and that includes a good 90% (at least) of TR owners. I wouldn't even think about omitting the MoT just because it isn't mandatory on pre-1960 cars, thanks a bunch, I'll pay my £30 and have the car independently checked. If a vertical link fails, then there must have been a significant problem present for some time, whether that was corrosion, previous impact damage, whatever - presumably not noticed by the diy maintenance regime ? Cheers Alec Quote Link to post Share on other sites
wjr85 Posted December 10, 2013 Report Share Posted December 10, 2013 (edited) Couldn't agree more with Alec on this one. John Edited December 10, 2013 by wjr85 Quote Link to post Share on other sites
vivdownunder Posted December 10, 2013 Report Share Posted December 10, 2013 Hi Brian, My last vertical link incident happened some years back when a mate's RH side let go. Lo and behold he has a head on with a wife's close friend and writes off her car. What odds in a city of nearly 4 million ?. Fortunately no serious injuries and the mate's TR3 was rebuilt to a very high standard. Anyhow the broken parts and LH vertical link went to a metalurgical laboratory for crack testing and analysis. Their summary was that the link had broken immediately above the trunnion thread, most likely as a result of a past hit (examination of the RH spring tower revealed prior accident damage). Apparently it could be many years before such a crack translated to a snapped link. Many of our owners then had both vertical links crack tested and cracks were found in two or three cars, all showing at the top of the trunnion thread. When getting vertical links crack tested, it's worthwhile to have the stub axles crack tested too, They've also been known to break, again most likely as a result of a crack developing after a hit. Viv Quote Link to post Share on other sites
brian-nz Posted December 10, 2013 Author Report Share Posted December 10, 2013 (edited) Hi Viv As it happens the break has occurred at the top of the vertical link thread. I had noticed that the car had suffered some sort of accident damage as the shock was a different make from the other side and also there is a small indent in the chassis behind the turret. I did not think to get link checked, my mistake. Disappointing as car has only been on the road for 3 months and summer is here. Would rather be in the car than under it. New link ordered and will get other one checked once left hand side back together. Brian Edited December 11, 2013 by brian-nz Quote Link to post Share on other sites
vivdownunder Posted December 11, 2013 Report Share Posted December 11, 2013 Hi Brian, Looking on the bright side, you are fortunate it didn't happen at highway speed. The sudden effect at 100kph with no steering, no brakes (hose ripped out), and the front corner of the chassis dropping onto the tarmac would be horrifying. That's why for some years now I've been advocating crack testing of the vertical links and stub axles as an essential part of a front suspension rebuild. We actually took it a step further and examined our club's stock of new vertical links. Some had a manufacturing fault with a crack showing in the top radius at the ball joint eye. Hopefully the resultant improvement in quality control by the maker has led to a safer product for all. Viv. Quote Link to post Share on other sites
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