3rd gear rattle

[speedbox]

A nyone any clues as to why our 65 1098 minor's gearbox has suddenly developed a really nasty rattle in third gear , as soon as you change into third it rattles badly and diminishes gradually as the engine speed increases and is all ok in all the other gears . Sounds a bit ominous doesn't it ? I have two spare gearboxes in the garage but is there any way of checking them out prior to fitting them to the car to minimize any chances of having to take them out again which i really don't fancy too much , any help much appreciated , many thanks Darren

[MoggyTech]

This can still be caused by the little anti rattle 'O' ring on the base of the gearstick, so try that first, as it's an easy fix. Remember than the gearstick is in a unique position in any gear, so just cos it's rattling in third doesn't mean the gearbox is faulty.

If it's not the anti rattle o ring/spring or plunger, it's likely to be a worn or loose selector fork. These can be tightened by draining the oil, and removing the gearbox side cover, after removing the clutch relay shaft. Watch out for the two springs that some out as you remove the cover.

It's unlikely to be the 3rd gear syncro hub, as the oil will kill rattles, assuming the gearbox is filled with 20/50 engine oil to the correct level.

[speedbox]

Many thanks for that sounds like a good start and a cheap place to start before steaming in and replacing the whole gearbox , i shall give it a go thanks again Darren