MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG Midget and Sprite Technical - Gearbox parts availability

Looks like I have bad 3rd gear synchro in my 73 1275. Looks like Moss and VB do not have these parts. Are they ones that can be sourced elsewhere or am I going to have to look at other options. I know a place in DC that sells refurbished gearboxes but wanted to look at cheaper options first. Trying to look at what alternatives I have.
Thanks,
Allan
Allan Jacks

Allan -
I think you are looking at the wrong parts, though my Moss book is old. You need "synchro ring" aka "baulk ring", not the synchro hubs which <should> be fine. 2,3, 4 all use the same ring. Moss 461-970. Also need to examine the layshaft and its bearings, as these are the weak points of the box, and bad ones will eat very expensive & rare gears.
Somebody more up to date than I ought to be able to tell you where to get good ones - esp the layshaft - there have been serious issues with quality over the years.

FRM
FR Millmore

Hi Allan,

I have some gear box spares so may be able to help you out, but are you sure Moss dosen't sell it? Which part number are you in need of?

James Eastwood

FRM,
Thanks for your info.
I see that Quantum Mechanics has a rebuild kit
http://www.quantumechanics.com/categories.php?op=newindex&catid=6
I am going to have find somebody in the area that has some experience with these as this is something that I am definitely not comfortable with.
Allan
Allan Jacks

Allan-
That should do ya! Might consider just taking the box to John rather than search for unknown persons.
Or call these guys:
http://www.motorcar-garage.com/
Pretty close to you and definitely good guys. Ed is a frequent contributor on the MGE Magnette board, who has done an amazing install of a 5 speed in a Magnette, and does stuff like make poly suspension bushes for all the Magnette guys. Pete was at 7 Enterprises (greatest Mini parts place ever) in the old days when they were in Virginia.

FRM
FR Millmore

Moss do not price the 3rs gear itself (22G1121, don't have immediate access to other supplier's availability) so if the problem includes the sintering on the gear face it could be difficult to resolve

Layshafts - we struck and gave upo on the quality issues. They are now induction hardened instead of case hardened with a resulting hardness which varies from 59 to 51 rockwell, against the original 61. As a result wear rates can be excessive. Same problem with MGB.

Our solution has been to get some made here, case hardened to 61 rockwell. Not cheap unfortunately but at least they are fit for purpose.
Paul Walbran

Gents,

I had a quick search on the internet and there were referances to the Morris Minor. However I couldn't find a parts diagram to confirm the gear is also used in the Minor.

The Morris Minor does have a different gear set with lower 1st, 2nd and 3rd gears. However I know that the input gear ratio to the layshaft is also different, and it may jsut be possible that the 3rd gear itself is common with the Spridgets, hence the web referances?

In which case getting a Morris Minor box might be a less expensive route (I just sold one for £30 on eBay, I have another but wasn't thinking to split).

Regards James
James Eastwood

22G1121 is unique to the midget mk3, Sprite mk4 box.
early Minor + Frogeye is 22A140
Sprite Mk2 is AEA3304
Sprite mk3 is AEA3032
All info is public domain and easily accessible, just takes a bit of searching and reading.
David Smith

As far as I know the Minor gears are a different ratio, not just in the input shaft but also the other gears. Cartainly there is a wider gap between the gears.
You also need to watch out for helix angle.
In my opinion, fitting a Minor box is a last resort even if it is a lot cheaper. The ratios are nowhere near as good.
Paul Walbran

Remember also that the quality of the new stuff as mentioned by PW above, is simply not there anymore.

A lot of the Mini autotest guys would rather use second hand first gears as they have been work hardened through use, the new ones tend to last a very short period before exploding.

Same applies to all the remanufactured box parts for our wee cars.
PeterJMoore

Foget the Morris Minor box, it's totally different inside with ratios, gear angles and bearings all totally different.

Try Peter May for good quality gearbox parts or Hardy Engineering. Both in the UK but worth the effort...

Mark.
M T Boldry

This thread was discussed between 05/06/2011 and 08/06/2011

MG Midget and Sprite Technical index

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