zogabu Posted January 2, 2011 Report Share Posted January 2, 2011 I wish to all TR enthusiasts a happy new year and a lot of fun with their classic. On my side, I am presently replacing all the suspension bushes that are in a rather poor condition. I chose to fit superpro product, after reading many topics on this forum. I start with the left side, keeping the right side intact, as reference to avoid mixing parts at reassembly time. I have faced what seems to be a well known problem: dismounting the trunnion that is completely seized on the pivot bolt. I succeed to remove it by cutting the bolt both side of the trunnion, drilling a large hole (about 10mm diameter) at the center, using a vice and a butane torch, the trunnion finally surrenders. (see sketch). I guess the same story will happen again on the right side. At least I know how to proceed. Now, my dilemma: Trunnion is a very critical part and any failure may have heavy consequences. I am not sure that the way I used to dismount it has not change something in the metal structure. Therefore I have purchased new parts at Moss that are supposed to be original equipment. The trunnions that I have received are looking good, dimensions are ok but there is no marking at all (see picture original trunnion at left, new one at right). Does anyone has experience of Moss trunnions ? Shall I reused the original trunnion ? Thanks a lot for your kind advise. Guy Quote Link to post Share on other sites
RobinTR6 Posted January 2, 2011 Report Share Posted January 2, 2011 I think you'll find that the threads are handed....so only fit one side. Robin Quote Link to post Share on other sites
zogabu Posted January 2, 2011 Author Report Share Posted January 2, 2011 I think you'll find that the threads are handed....so only fit one side. Robin Robin, I know left trunnion is different than right one, but this was not my question. Shall I install again the original trunnion, that could have been damaged during dismounting, or install the new ones that I got from Moss for which I have a doubt about quality ? Regards. Guy Quote Link to post Share on other sites
RobinTR6 Posted January 2, 2011 Report Share Posted January 2, 2011 Apologies. I'd assume that if the suspension was worn and the trunions seized on, given they are brass and soft I'd go for the new ones. Others may have already used the Moss replacements so lets see what they opine. I have replaced mine with TRGB ones but I suspect that they will from the same supplier as Moss. Regards Robin Quote Link to post Share on other sites
RogerH Posted January 2, 2011 Report Share Posted January 2, 2011 Hi Guy, the removal of the seized bolt should have done no damage. The heat from the butane lamp would dissipate fairly easily through the mass of the trunnion and vice. The Trunnion has no special hardness/tempering characteristics that the heat would affect. How does the old trunnion feel on the thread. It will probably screw on easily but you don't want too much play up and down. The new one may not even screw on properly ( I think some are turning up that have poorly cut threads). Also is there a problem with the base plate in the bottom not sealing very well. Assuming that the old one feels nice when screwed into position I would go with that. Don't forget to lubricate well during assembly. Grease is the norm but some are using thick oil (EP140 etc). Roger Quote Link to post Share on other sites
TR NIALL Posted January 2, 2011 Report Share Posted January 2, 2011 (edited) Guy,on reassembly i would use EP90 Gear Oil and not Grease,if using the new Trunnion inspect the bottom of same as when these new ones are cast they only use a blank washer type bottom that will leak Oil as they are sealed badly,these need to be sealed by soldering,if your old ones are the solid cast type you will notice the difference on both types,which ones you use is your choice, im sure you can make a better judgement after close inspection of both types. Edited January 2, 2011 by TR NIALL Quote Link to post Share on other sites
stuart Posted January 2, 2011 Report Share Posted January 2, 2011 I fitted one of the new Moss ones last year on my 4a after the Isle of Wight roads had "eaten" one of mine and I was actually impressed with the fit as the thread was perfect. Though Nialls suggestion of soldering the bottom plate in is a good one as they will leak oil otherwise. Stuart. Quote Link to post Share on other sites
Davidw Posted January 2, 2011 Report Share Posted January 2, 2011 I found that coating the base plate & surrounding area with araldite also acts as a very effective seal. Quote Link to post Share on other sites
zogabu Posted January 2, 2011 Author Report Share Posted January 2, 2011 Thanks for all the advises. The vertical link is presently at the paint shop. Once it will be back, I will check the play with both the old trunnion and the new one.Then, I will make the decision. both new and old ones have a steel bottom plate. Not easy to know whether old ones were leaking or not, as everything is more or less oily in this area. Further question : how to weld brass to steel ? Regards. Guy Quote Link to post Share on other sites
stuart Posted January 2, 2011 Report Share Posted January 2, 2011 Further question : how to weld brass to steel ? Regards. Guy You dont. Solder them up instead. Stuart. Quote Link to post Share on other sites
Alec Pringle Posted January 2, 2011 Report Share Posted January 2, 2011 I wouldn't have any qualms about the Moss trunnions. They're about as good as we're likely to get. Last year in the course of a day at Pete Cox's I met the chap who actually makes the trunnions, an enlightening discussion ensued on the difficulties involved, variables, etc etc. One result being that I sent up a small box of virgin Stanpart nos trunnions of different vintages from my own stock, to be electronically 3-D scanned - Moss have had scanned dozens of the things to try and establish the tolerances and limits of production variations through the years. Significant variations, I might add ! Quite amazing to learn just how many hours and pound notes have gone into researching this particular item, hidden costs that we on the buying end don't even think about. I had no idea of the scale of the efforts that have gone into analysing a whole range of these mundane mechanical components that we all take for granted. Nor had I appreciated just how many assorted pieces of legislation potentially impinge upon the reproduction of classic parts - hearing chapter and verse of what was involved in reproducing TR6 wheels, for example, was quite an eye opener. Bloody nightmare, no wonder the things cost serious money. Cheers, Alec Quote Link to post Share on other sites
TR NIALL Posted January 2, 2011 Report Share Posted January 2, 2011 Hi Alec,do you know if the Moss ones need sealing/soldering at the base,if yes why can the Manufacturer not do this,i find it amazing that one buys a Trunnion and then has to rework it for it to be able to be of any use,it is most annoying to fit the leeking ones only to find that you then have to remove them to seal/solder them. Quote Link to post Share on other sites
Alec Pringle Posted January 2, 2011 Report Share Posted January 2, 2011 Hi Niall, I doubt they need soldering, but I'll refer your comments to Pete Cox and see what he has to say. Cheers, Alec Quote Link to post Share on other sites
Guest ntc Posted January 2, 2011 Report Share Posted January 2, 2011 I wish to all TR enthusiasts a happy new year and a lot of fun with their classic. On my side, I am presently replacing all the suspension bushes that are in a rather poor condition. I chose to fit superpro product, after reading many topics on this forum. I start with the left side, keeping the right side intact, as reference to avoid mixing parts at reassembly time. I have faced what seems to be a well known problem: dismounting the trunnion that is completely seized on the pivot bolt. I succeed to remove it by cutting the bolt both side of the trunnion, drilling a large hole (about 10mm diameter) at the center, using a vice and a butane torch, the trunnion finally surrenders. (see sketch). I guess the same story will happen again on the right side. At least I know how to proceed. Now, my dilemma: Trunnion is a very critical part and any failure may have heavy consequences. I am not sure that the way I used to dismount it has not change something in the metal structure. Therefore I have purchased new parts at Moss that are supposed to be original equipment. The trunnions that I have received are looking good, dimensions are ok but there is no marking at all (see picture original trunnion at left, new one at right). Does anyone has experience of Moss trunnions ? Shall I reused the original trunnion ? Thanks a lot for your kind advise. Guy Guy Test them yourself put them in a vice screw in the vertical link dry and back of 1 turn and judge the movement by levering. The least wins Quote Link to post Share on other sites
AndrewP Posted January 4, 2011 Report Share Posted January 4, 2011 Without hijacking this thread, but this has raised a few questions that I have about trunnions. Firstly, how does one go about checking them and what should you check? Where do they wear and whats considered 'throw away' as opposed to passable.? Secondly, the Moss units have already been mentioned, but has anyone used the sets from some of the other suppliers (Rimmers, SC Parts etc?). Id like to know firstly if my set are OK, and if not, which ones to order, given Rimmers have a single trunnion for 30 quid, as opposed to Moss's at 45 quid (50% more expensive)..are they all created equal? Thanks for any feedback. Cheers Andrew Quote Link to post Share on other sites
stuart Posted January 4, 2011 Report Share Posted January 4, 2011 There has always been some dodgy ones around I cant comment on the others but the new Moss ones are good. Remember you get what you pay for. I have seen cheap ones worn out in 3000 miles. If you can get appreciable up and down movement of the trunnion to the upright and the threads on the upright are good then its time for a new trunnion. Stuart. Quote Link to post Share on other sites
zogabu Posted January 26, 2011 Author Report Share Posted January 26, 2011 Hi all, Some information, as conclusion for this thread: I have received the parts from the paint shop and take some measurement on the vertical link + trunnion assembly with both used and new Moss trunnions. The figures are - End float (up down) : 0,03mm with the used trunnion and 0,02mm with the new one - Radial clearance (measured at the point where the rod lever is attached to the vertical link) : 0,35mm with both the used and the new trunnion. This confirms that the used trunnions are still in good condition and, also, the quality of the Moss trunnions. To save the cost of shipping back trunnions to Moss, I will install the new ones and keep the old ones as spare. I attach a picture of the front suspension, as it is was before and as it is today. Believe me or not, it looks a lot better than my daily Citroen ! Thanks to the assistance that the TR community is providing to newcomers like me. You make us feeling more comfortable with our toy, and I will open a new thread about the camber adjustment. Guy Quote Link to post Share on other sites
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