Clutch thrust bearing "upgrade"

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Philip Tibbitts
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Clutch thrust bearing "upgrade"

Post by Philip Tibbitts »

Has anyone installed one of the "upgraded" roller bearing clutch thrust bearings, replacing the OE carbon one?

Are they good to use, or do they cause quicker thrust bearing failure?

Moss have been selling them for some time - so how did they get over the non-concentricity running of the bearing surface due to the arc caused by the actuating arm, with induced premature failure ?
Ian F
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Re: Clutch thrust bearing "upgrade"

Post by Ian F »

Philip, I think you have identified what is generally considered to be the main problem with the roller bearing design. For my part, I decided to stick with the original design of carbon bearing - always worked perfectly for me so I didn't see any need for an"upgrade".
I may be a bit resistant to change, but it seems to me that the majority of the "upgrades" offered are principally designed to extract funds from our pockets!

Ian F
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1972 BGT, Blaze, Navy trim, recessed grill
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Vic Butler
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Re: Clutch thrust bearing "upgrade"

Post by Vic Butler »

I've heard that there are misalignment problems with these roller bearing thrust bearings. It seems a good idea but like all good ideas there's always a downside. Stick to the good old carbon thrust bearings, they've been used for decades. If the roller bearing one was better maybe it would have been factory fitted.
I agree with Ian. It's a gimmick to make you part with your money.
1977 Stage 2 MGB GT
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Paul Heffernan
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Re: Clutch thrust bearing "upgrade"

Post by Paul Heffernan »

I'm no expert but this makes sense to me:

https://www.youtube.com/watch?v=4KIdkOW ... e=youtu.be
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Peter Cresswell
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Re: Clutch thrust bearing "upgrade"

Post by Peter Cresswell »

I considered using the roller bearing type when I fitted a new clutch during the engine rebuild, but decided against it on cost as the carbon type came with the AP kit, and I had never had a problem with the carbon type on any car in the past. The problems highlighted above and in the YouTube video set me thinking, as Fords I have had used the roller type. In this case though the carrier is pivoted on one side of the bell housing and has a hole for the input shaft to the gearbox to pass through. The carrier then go through a cutout in the side of the bellhousing for the cable to connect to. The movement then is much less of an arc than the MGB has and the bearing pivots top and bottom so the bearing meets the clutch cover assembly square on. Ford also developed a self centering release bearing.
Pete
1969 MGB Roadster
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Plus 34 other cars since 1965
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