Roller bearing thrust release

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Oldmogman
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Roller bearing thrust release

Post by Oldmogman »

Has anyone fitted a roller bearing thrust release? What are they like?

I think I heard there might be an issue with the way it aligns in the clutch fork, but I would have throught that since the thrust bearing is free to swivel in the u-shaped cups of the clutch fork, there wouldn't be a problem?


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philthehill
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Re: Roller bearing thrust release

Post by philthehill »

The problem with the roller release bearing is that it is not concentric to the clutch cover release plate when moving through its operational arc. This means that the steel roller bearing skids on the release plate of the clutch cover which can lead to excessive wear.
To get over the problem the release arm pivot hole can be slightly elongated. This allows the roller release bearing to be drawn concentrically to the release plate of the clutch cover so eliminating the skidding.
I have had adopt a similar solution for the concentric roller release bearing mechanism fitted to the Ford gearbox installed in my Minor.
I have a steel release arm pivot bracket with elongated pivot bolt hole fitted inside the adapter gearbox bell housing.
The benefit of using the carbon thrust is that it is able to adapt to the non concentric function and skid at ease. The problem is that not all currently available carbon thrusts are up to the right quality and are prone to fail.

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svenedin
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Re: Roller bearing thrust release

Post by svenedin »

In a standard set up (engine and gearbox) the original carbon thrust bearing is actually very good. It lasts a long time providing care is taken with use of the clutch. Never sit at traffic lights with the foot on the clutch or drive along riding the clutch pedal. Always take the car out of gear, release the clutch and put the handbrake on when waiting at traffic lights. The carbon thrust will outlive a clutch if care is taken with driving. Unfortunately, the new carbon thrust bearings are often not of satisfactory quality according to many reports.

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
Oldmogman
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Re: Roller bearing thrust release

Post by Oldmogman »

Thanks guys, good to know.

In that case, would anyone know which are the better brands of new carbon thrust bearings and who sells them? EMS, perhaps?
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King Kenny
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Re: Roller bearing thrust release

Post by King Kenny »

EMS are a good as any. I have never worn one out in 46 years of driving my Traveller.
1969 Traveller in Almond green. Owned since 1979.
kevin s
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Re: Roller bearing thrust release

Post by kevin s »

I have a concentric slave with a roller bearing, a fair bit of work but lovely light progressive clutch.
kevin s
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Re: Roller bearing thrust release

Post by kevin s »

in fact I've got at least one brand new carbon bearing which is no use to me if you want it.
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