08-01-2025, 08:35 PM
(This post was last modified: 08-01-2025, 08:38 PM by Steve Jones.)
Using a four speed release bearing on a three speed gearbox is a common modification. As has been fitted, four speed levers are more suitable for the later bearing than the three speed levers. However, when doing this modification clearances change and as a result, some fettling is required. To decide what's required, always fit the engine and gearbox together on the bench so you can see if sufficient clearance between the release bearing carrier and the levers exits and, if not (usually the case), you can do the required adjustment there and then rather than finding out you have an issue after you've fitted the engine and box into the car. I follow the route that Terry Griffin recommends and it's always worked perfectly. However, even then, sometimes a set of washers is also required as the various posts above detail. Each combination of engine, release bearing/carrier and gearbox seems to be slightly different. Machining some thickness off the rear of the bearing carrier may achieve more clearance (at the possible risk of removing some strength from the carrier which takes a significant load) but why would you when much simpler options are available and are recommended by the many that have successfully fitted a four speed release bearing?
Steve
Steve