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MG Midget and Sprite Technical - 1500 reverse gear selection

Ever since I have had my car I have had a slight issue with reverse gear selection on the Triumph 1500 single rail box.

To select reverse you lift the lever and pull over to the driver before pushing forward. On my box if I'm not careful I can end up pulling the gear stick right over to the right and beyond reverse. Clearly something is going wrong with the selection mechanism.


Its something I have learnt to live with and I can select reverse by feel. But if my wife tries the gear stick ends up jammed over to the right at a weird angle.


I'll be taking the engine out soon so it will be a good opportunity to sort it out. Has anyone else had this issue ? Archives and Googling doesn't throw up anything.
Chris Madge

it souds like a problem with the reverse lift plate it just bolts on the gear box ,when i first got mine it was missing and selecting reverse was fun
mark heyworth

Weird one. Could be the stop on the gearbox tail under the gear stick. You can access this via the gear stick hole. Whip off the knob and gaitors, take the stick off and take the stop off (one 1/4 inch bolt). It might be badly worn, a bit of weld and dressing will sort this.

But... thinking whilst I type... this should only stop you from getting reverse when you want third. Sounds maybe like the stop plate or other associated bits inside the gearbox itself are worn or missing.

It could have been forgotten by a previous re-builder, as it just sits on the top of the casing before you put the gasket and lid on the box.

http://www.moss-europe.co.uk/shop-by-model/mg/midget/clutch-gearbox-drive-train/gearboxes-components/external-gearbox-midget-1500-1974-79.html

90 is the plate that determines the left/right throw. 85 is a funny shaped thingamabob that works with 90 to define the gearbox "gate".

Malc.
Malcolm Le Chevalier

Thanks Malcolm and Mark, interesting. The last time I took the engine out I lifted the lid off the gear box and that plate #90 was there. I didnt check if its got the reverse lift plate and I didnt investigate anymore before getting the box refurbished. (bearings, seals, and syncros only)

However the problem was there before and after the refurb.

Thinking out aloud here.....
I have a spare gearbox with a knackered layshaft, but its complete and as far as I know works ok. If the gear selection on that box is good, i can swap worn/missing bits when I take the engine out in a few weeks.
Chris Madge

For those with a 1500, I finally got round to looking at this whilst the engine is out of the car.

The stop plate was there and doing its job.

I think I have found the culprit. The longer of the two locating pins (97) which locates the spherical cup (96) down onto the gearbox and also the locates into a groove in a ball at the bottom of the gear stick. The pin was so worn that the gear stick could rotate by 30 degrees.

As you lifted the gear stick up and pulled it over to the right to select reverse the gear stick was twisting anticlockwise. So much so that the end could miss the yoke on the end of the selector shaft to engage reverse. The the lever ended up in a bizarre far right position with no gear engaged.

A replacement pin has stopped the gear stick rotating and reverse gear selection seems a lot more positive.



Chris Madge

Everyday's a school day! :-)
Malcolm Le Chevalier

This thread was discussed between 15/11/2019 and 04/03/2020

MG Midget and Sprite Technical index

This thread is from the archive. The Live MG Midget and Sprite Technical BBS is active now.