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MG MGB Technical - Crunch engaging reverse

I seem to have a problem when trying to engage reverse in my '77 GT. Sometimes (not very often) it will slip in to reverse nice and easily but most of the time it won't go in first time.
No matter how hard you try and force it it will usually not select, you have to take your foot off the clutch, move the gear stick from side to side, put your foot back on the clutch and try again. This solves it sometimes but it usually still needs a bit of force to get it in and it almost always crunches as it goes in.

I recently changed the gearbox oil which doesn't seem to have helped.

Does this indicate that the reverse gear is ruined or is this 'normal' as some people keep telling me?
K Goldup

No its nothing to do with the gearbox. Its to do with the clutch not freeing up completely. There is no synchromesh on reverse - it is a straight cut gear so to slide in quietly, firstly the gears must not be spinning and second the teeth must line up.

It sounds like you have a little stickiness in the clutch that keeps things spinning when the pedal is down - don't worry about this, its very common and doesn't indicate imminent failure. The baulking is because the teeth are out of line.

What I always did was to briefly select a forward gear (2nd gear is good) before selecting reverse. All the forward gears have synchromesh so that stops the gears and allows silent engagement. Then without lifting the clutch pedal, slip out of forward gear and into reverse. It should go in quietly.
Mike Howlett

Yes, exactly what Mike said. You don't want to select reverse before you have selected a forward gear (like 2nd) first. You have to stop the motion before selecting the gear.

Charley
C R Huff

Sounds like standard gearbox to me, especially BL although I have known it on other makes. Whilst my V8 does seem to take a moment to stop spinning when dipping the clutch and will crunch if pushed into reverse too quickly I have never known this on the 4-cylinder. A pal with a V8 had the same thing so it's not just mine. Baulking is another issue, most of the time it will go into 1st or reverse first time, if it baulks in first a quick half selection of 2nd usually allows 1st to go in. With reverse sometimes a half selection if 1st is required, sometimes a half selection of 2nd then 1st, and sometimes not even that works so it is up with the clutch and back down again. None of these issues are to do with the clutch not releasing fully, if that were happening reverse would crunch much more, and would continually crunch if you ease the lever towards reverse so the 'teeth' are just touching, and forward gears would require a harder shove to get them in. This is a different feeling to baulking.
PaulH Solihull

This thread was discussed between 18/05/2011 and 27/05/2011

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