Herald rear trunions..no lubrication?

[Barry Kemp]

Having replaced my front trunions recently  I moved on to the rear ones.I was surprised to find  that there  is no  way to  lubricate them in-situ.

Is this a design fault? 

The set of replacement trunions fit so tightly into the housing that it looks really difficult to get any lubricant around them. This only leaves the metal sleeve that can be lubricated - so why are there rubber seals that fit around the trunion/ between each of the two metal end pieces?

 

 

[Colin Lindsay]

Probably to keep dirt out whilst allowing the joint to swivel around the sleeve; they don't move as much as the front ones do so don't need the same kind of lubrication. The bushes are a firm fit in the housing and rotate around the bolt whilst the metal sleeve prevents direct wear on the rubber. A squirt of copper grease into the metal sleeve will prevent the bolt from sticking to it. 

It's also amazing the number I've seen that are tightened up fully with no mission of ever moving as they were designed to.

[Pete Lewis]

To add , the fronts you are oiling the swivel for steering , not the trunion suspension pivot which is the same as the rear 

Its a dry bush  a, crush tube that rotates in the bush and the nasty tin shrouds and 0 rings seals same front and rear to keep water and road dirt out of the bushes

 

[PeteH]

On 22/02/2018 at 7:19 PM, Colin Lindsay said:

Probably to keep dirt out whilst allowing the joint to swivel around the sleeve; they don't move as much as the front ones do so don't need the same kind of lubrication. The bushes are a firm fit in the housing and rotate around the bolt whilst the metal sleeve prevents direct wear on the rubber. A squirt of copper grease into the metal sleeve will prevent the bolt from sticking to it. 

It's also amazing the number I've seen that are tightened up fully with no mission of ever moving as they were designed to.

The Bolt is tightened onto the Inner Sleeve, If it locks the Trunnion up solid, then I would suggest the machining of the Sleeve lengthwise is incorrect?.

[Pete Lewis]

yes the sleeve/bush must be locked up between the dust cups and  against the upright  the design is as  such the  bush rotates about the sleeve , the sleeve must not rotate about the through bolt 

they are pretty tight to swivel when assembled  the sleeve is a neat fit in the bushes .and its not lubricated  front or rears all are dry  , used to be called self lubricating.

only in as much as the nylon cant pyhically seize on the steel  sleeve.

Pete

[Colin Lindsay]

On 2/26/2018 at 11:22 AM, PeteH said:

The Bolt is tightened onto the Inner Sleeve, If it locks the Trunnion up solid, then I would suggest the machining of the Sleeve lengthwise is incorrect?.

It's the ones that are screwed up so tightly that they flare the ends of the metal tube... some of the 'kits' don't show which tube goes with what, so you do get incorrect fittings from time to time. Not to mention the ones that are rusted solid after thirty-odd years of neglect.

[PeteH]

7 hours ago, Colin Lindsay said:

It's the ones that are screwed up so tightly that they flare the ends of the metal tube... some of the 'kits' don't show which tube goes with what, so you do get incorrect fittings from time to time. Not to mention the ones that are rusted solid after thirty-odd years of neglect.

 

Ah! Yes!. like the ones I had to get very "physical" with. Welded a stud to the bolt head in the end and used tube and washers to draw it out whilst "massaging" the threaded end with a lump hammer!.

[68vitesse]

Fitted polyurethane bushes to the rear trunnions of my Mk1 Vitesse as part of a job changing all possible bushes. In my opinion the crush tube was to long allowing the trunnion to rock, ended up reducing the length to the same as the tube for the spring eye bush.

Used silicone grease on the bush and copper grease on the bolt.

Regards

Paul