m807ppp Posted May 14, 2015 Share Posted May 14, 2015 Is there a fall proof way of checking trunnions on a 1978 spitfire, ie checking for movement, I've had my spitfire for two months, and am inclined to just replace them regardless of condition then I know these are ok, or else i'am tempted to check for movement, and if there is none fill with ep90 Quote Link to comment Share on other sites More sharing options...
heraldcoupe Posted May 14, 2015 Share Posted May 14, 2015 It's not the trunnion itself which usually fails, it's the vertical link which breaks at the point where it exits the trunnion. Wear is easy enough to detect, but rust spots giving rise to stress fractures won't be detected without stripping down the link.Cheers,Bill. Quote Link to comment Share on other sites More sharing options...
Nick Jones Posted May 15, 2015 Share Posted May 15, 2015 Wear can be checked by raising the front of the car so the front wheels are 1" or so above the ground then using a bar (jack handle) between the tyre and the ground to lever the wheel upwards. Watch the meeting between trunnion and vertical link (where the rubber sealing ring is) for movement. There should be none visible. I also repeat the exercise while gripping the joint area with my spare hand so I can also feel for movement. This should be barely detectable. If there is excessive movement then it is usually cured by renewing the brass trunnion. The vertical link can be inspected at the same time. The critical area is the very top of the treading section which is where any cracks/breakage tend to occur. Corrosion at this point is a reason to renew the link IMO.Note that in my experience your average modern MoT man is unable to detect worn trunnions, especially if he uses one of those mechanical suspension testers. I have discovered a very tired trunnion right after passing an MoT....... so don't assume recent MoT = ok trunnions!Nick Quote Link to comment Share on other sites More sharing options...
Velocita Rosso Posted May 15, 2015 Share Posted May 15, 2015 Nick_Jones wrote:Wear can be checked by raising the front of the car so the front wheels are 1" or so above the ground then using a bar (jack handle) between the tyre and the ground to lever the wheel upwards. Watch the meeting between trunnion and vertical link (where the rubber sealing ring is) for movement. There should be none visible. I also repeat the exercise while gripping the joint area with my spare hand so I can also feel for movement. This should be barely detectable. If there is excessive movement then it is usually cured by renewing the brass trunnion. The vertical link can be inspected at the same time. The critical area is the very top of the treading section which is where any cracks/breakage tend to occur. Corrosion at this point is a reason to renew the link IMO.Note that in my experience your average modern MoT man is unable to detect worn trunnions, especially if he uses one of those mechanical suspension testers. I have discovered a very tired trunnion right after passing an MoT....... so don't assume recent MoT = ok trunnions!NickIn other words its knowing your TR onions.... :B Quote Link to comment Share on other sites More sharing options...
DougBGT6 Posted May 15, 2015 Share Posted May 15, 2015 My MOT man failed my car for slack trunions, when I took it back he tested them exactly as described. He'd been an apprentice in a Triumph dealership and says he looks forward to seeing my car. He knows a little too much about Triumphs for my liking! Quote Link to comment Share on other sites More sharing options...
m807ppp Posted May 15, 2015 Author Share Posted May 15, 2015 I've checked for movement and it virtually undetectable, a very slight hardly noticeable movement, so am I right in thinking this is ok. Quote Link to comment Share on other sites More sharing options...
Nick Jones Posted May 15, 2015 Share Posted May 15, 2015 Ok for wear. Could still be rusty but if it's all fairly oily there it suggests someone's been oiling them (as does their not being knackered) and they'll likely be fine.Nick Quote Link to comment Share on other sites More sharing options...
m807ppp Posted May 16, 2015 Author Share Posted May 16, 2015 I have decided to change trunnions as they are full of grease, and I know no history about them, Quote Link to comment Share on other sites More sharing options...
Paudman Posted May 17, 2015 Share Posted May 17, 2015 You don’t need the history; just clean them and inspect them… especially when as Bill says it’s the vertical link that wears and snaps. No amount of new trunnions will cure or compensate for wear on the link at this point, although I suppose a new set of good(!) trunnions will at least put your mind at rest regarding that area of the suspension units. If the link is in any way suspect, replace. Quote Link to comment Share on other sites More sharing options...
DougBGT6 Posted May 17, 2015 Share Posted May 17, 2015 I've had a vertical link snap, an invigorating experience so say the least! ??) My car's PO thought lubrication was for wimps. As stated check the thread right at the top, any deterioration, ditch it. Regarding grease, grease was once water based and turned to damaging powdery grit so Triumph changed to oil for trunions. Oil is a better lubricant in this application but grease is no longer water based and your PO may not have done any damage using it. Quote Link to comment Share on other sites More sharing options...
john2502 Posted May 17, 2015 Share Posted May 17, 2015 As others have said its the vertical link that really needs the inspection and will show wear.I decided to go trunnionless from Canleys when I did my rebuild so I never had to even think about them again which is nice. Little bit pricey (not loads more than 2 new vertical links though)http://www.canleyclassics.com/suspension-steering-and-brakes/trunnionless-front-suspension-kit/Although well maintained trunnions/VL's will of course work well. Quote Link to comment Share on other sites More sharing options...
Velocita Rosso Posted May 18, 2015 Share Posted May 18, 2015 Having had two VL snaps, one in the `70s and one about 14 years ago, it was still a basis for investing in trunnionless.It was always at the back of mind, when whipping around mountain passess on the 10 CR or on autosolos, that the stress put on that weak area of the suspension would eventually tell in the form of a snapWhen you think about how small a diameter of metal is that holds the front end up , whether lubricated or not, its a bit un nerving.Trunnion less is great,just for piece of mind, allowing you to have a relaxed drive ,knowing you would not have three wheel on your wagon.Not only that, but the conversion allows a far easier manageability on steering....a lot more free turning Quote Link to comment Share on other sites More sharing options...
Paudman Posted May 18, 2015 Share Posted May 18, 2015 It’s interesting in that the threads wear, but the top of the link snaps off! I’ve had both, a link breaking off and a trunnion jumping off the bottom due to having insufficient threads to hold it on.You can see the difference between a newish one and a well-worn one in the photos below, and work out from that how much wear there is in yours. Quote Link to comment Share on other sites More sharing options...
JohnD Posted May 18, 2015 Share Posted May 18, 2015 Is it so surprising? It's the top of the thread that is exposed to water and weather, and where the stress is concentrated.John Quote Link to comment Share on other sites More sharing options...
Velocita Rosso Posted May 18, 2015 Share Posted May 18, 2015 JohnD wrote:Is it so surprising? It's the top of the thread that is exposed to water and weather, and where the stress is concentrated.JohnMany years ago I had an MOT advisory that the tapered top rubber seal was missing,for some unknown reason, and that is where the top of the threads needs grease slapping all around and under the seal to prevent corrosion Quote Link to comment Share on other sites More sharing options...
Casper Posted May 19, 2015 Share Posted May 19, 2015 Quote:grease!!C. Quote Link to comment Share on other sites More sharing options...
Paudman Posted May 21, 2015 Share Posted May 21, 2015 1337 wrote:!!C.Yes, grease - oil would run off…. and it’s the metal around the top we’re protecting here, not the threads of the link which need the fluidity of oil. Quote Link to comment Share on other sites More sharing options...
yorkshire_spam Posted May 21, 2015 Share Posted May 21, 2015 I used Land Rover "one shot" grease in mine, formulated to replace the EP90 in Landy swivel housings. It seemed to be fine, but once the MOT guy reported "a bit of lift in the front trunnions" I just replaced with Canley's kit. Quote Link to comment Share on other sites More sharing options...
Velocita Rosso Posted May 21, 2015 Share Posted May 21, 2015 1337 wrote:!!C.Yes grease...Oil in the v/link.....grease around it and under the rubber sealThen no water can get around the neck or dribble down the threads Quote Link to comment Share on other sites More sharing options...
.thumb.jpeg.b15b81ef10abeea1c3039ae03c4a9f3a.jpeg)
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.