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Triumph TR6 - Trunnion pivot bolt
|Re the front suspension, can the lower trunnion pivot bolt be "pressed out" of the trunnion body or is forever part of the trunnion?|
(I have a 4A, but it appears that the front suspension is essentially the same as a 6).
As I recall the bolt is part of the main body behind the brakes..to remove the trunnion it unscrews from the bolt.
I can send you a couple of pix of mine apart a couple of years ago
|Hi Dennis, |
the bolt will press out... do not clobber it with a hammer unless you use a bronze drift or it will swage the bolt and you will have to cut it to remove it. In all likelyhood you will be replacing these bolts and the related bushings before reassembly so just getting them out while leaving the bronze trunion in good shape is key. Only use moderate heat if at all on the trunion but heating and rapidly cooling the bolt may be advantageous to releasing it from the metal sleave that seams to hold fast to the bolt and trunion.
|I must be missing something here but it sounds like there is 2 different things talked about.|
1:The trunion Screws into the vertical link (it is a reverse thread and the trunion and vertical link are left and right). It WILL unscrew from the vertical link with EXTREME ease.
2: the trunion is "sandwiched" between the 2 lower wishbones with a long bolt and a bunch of washers, water seals, and spacers. It is held in place with a slotted nut and cotter pin through the long bolt. It is not torqued down and will only be held in place by rust. There is a replacement kit (2 required) for this stuff as it gets crushed as you install it.
There is nothing "pressed in" down in this area of the front suspension.
The trunion is lubricated with oil not grease.
This suspension goes from TR4A/5/250/6.
|Here is a picture of it all courtesy Rimmer Bros.|
|Part no. 80, the trunion's lower pivot bolt and the largest bolt in the entire suspension sysetm, often will rust tight in place inside the steel bushing, part no. 81, and rusts to the trunion itself. I believe this is the part that is causing Dennis problems in removal. Correct that it does not screw into the trunion but it corrodes to the trunion and is very difficult to remove. This is where the idea of using a press comes into play. If you have access to a lathe it may be worth center drilling the new #80 and cross drilling at the bushing points, tap the 'head end' of the bolt 1/4-28 and install a grease zerk. Makes it easy to keep lub on these rather fragile bushings. Upon re-installment, make copper anti-sieze your friend on the steel bushing #81.|
Now I see the conversation. The words pressed out got me....sorry. I agree it will be rusted in place as I said. The replacement kit comes with this bolt and all the pieces which need replacing anyway so why not just hammer it out?
Definitely agree on the anti-seize.
What gets antiseize and what gets loctite?
|Doug, all major bolts in this area are secured by castle nuts and cotter pins so loctite isn't needed.|
Dennis, I just did this job last week and I found that the brand new trunion pivot bolts No.80 that came in the kit had been drilled incorrectly. The cotter pin hole had been drilled off center making them useless.
So rather than send the kits back and wait for new ones I just used the old bolts. The old bolts if they are in good shape might save you some time if you get one of these bad kits. The poly urethane kits are alittle more expensive but really crisp up the handling.
Your eyes are playing tricks with you. Never mentioned loctite. The bolt Chris talks about, it gets anti-seize. The whole shaft of the bolt not just the thread gets anti-seize. Like Chris said, cotter pin holds the nut so not tight at all. The shaft of the bolt goes through the trunnion, the 2 lower wishbones, and sleeves so you want to prevent seizing together.
Chris, I would still send the bolts back on principle.
|Hey Rick, Chris,|
I understood the antiseize for this appication. My question was more generic in which connectors throughout ought to get antiseize and to which is loctite recommended? I would assume for example, antiseize on the exhaust maniford to downpipe connection and loctite on bell housing bolts, but is there a general principle to follow? Maybe antiseize so that you can subsequently remove the connector more easily and loctite where you cannot use safety wire or other securing, but absolutely do not want the connectors to come loose? Should loctite be used on engine bolts?
Rick, I misplaced my glasses, but since I got "new" eyes (lens replacemnt, catarrat surgey), I don't use 'em too much:)
You answered your own question.
Engine bolts....do you mean inside the engine? An engine expert shoud answer this question.
|Doug, I would use a thread locking liquid only on critical bolts that do not have any other locking means... lock,serated, starred or safety tabbed washers, cotter pins etc. I would not loc-tite engine bolts that have a specific torque setting.... but always clean the internal and external threads and lightly lubricate before torquing. The only part I can think of loc-titing would be the clutch fork pin/bolt. I have never had a torque-critical bolt back off in 30 years of playing this game.|
Anti-sieze is another question, however, and I tend to use this on lower chassis components suject to corrosion and high heat components like the bake calipers, mannifold and exhaust system.
Hope this is useful,
|Wow, lots of great ideas, as usual.|
The offending items have been well soaked in "PB Blaster" and will continue to "marinate" for a few more days. I'll then try using my trusty 2 lb.sledge, buffered with a block of oak, on the ends of the bolts.
If this fails , it's off to my corner garage where we'll try the 10 ton bearing press. If that fails....
BTW, why did TR use brass(bronze?) for the trunnions when everthing else on the front suspension is forged steel or cast iron and weighs a ton?
|Dennis, the bronze of the trunnion is the sacrificial|
part that mates up with three other parts. If it were made out of steel then you would have 4 parts wearing
out instead just one.
You could also try a heating it up with a torch before resorting to the press.
Before I tried heat or a hydralic press, I'd liberally apply "Aerokroil", a marvelous product for releasing frozen connectors. Google AeroKroil on the web. It's manufactured by a lab in Nashville, TN and is quite simply the very best penetrant available. It's said to penetrate 1/1,000,000 of an inch. That's what we'c call a little sucker!!
This thread was discussed between 09/01/2007 and 16/01/2007
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