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MGB 66 mgb trans noise

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The rear bearing is a press fit onto the main shaft. A block of wood and a hammer on the rear extensoin is how i remove it. You did remove shift tower and the interlock part under the 6 bolts under the tin cover right? After thats removed the shift fork in there can drop out of the way. If you did not do that the shift forks would probably try to pull all the gears rearward when you try to remove the extension. ????? bob
 
I think that's what's happening. Not enough HAMMER.
 
Guess I was too gentle. Used blocks of wood between the main section and rear section for a little pressure and used a hammer on the output shaft. She came apart. Onc thing I did notice is the dowel on the main bearing is bend downward in the direction of the main shaft?? The hole for the dowel in the case is also oblong. Doesn't look right to me but apparently worked. I still have not been able to find any evidence of why the grinding when switching into second. The syncro is not that worn on the teeth, but it appears the inside may be pretty well worn. I read somewhere that you should be able to fit a .020 feeler between hub and syncro and feel little or no resistance. Is this accurate?? The 3 springs for the balls measure at .444-.45". Are these ok for service? Thanks for all the help.
 
The I.D. of the ring is what does the work. It "clutches" the cone of the gear to slow rotation. The teeth are only for alignment of the collar gear.

Pleased to hear you got it apart, not so pleased the dowel is bent. Can't imagine how THAT would happen other than abuse while the thing was apart at some point in its life.
 
There is no clearance on the 1st syncro at all. Definitely the problem. Last question. These syncros are brass in color. I am going to be driving this car maybe 2k miles a year at best. Should I be ordering the brass syncro? I'm guessing the iron syncro is not brass colored....
 
It has a dull gray look to it. More like mottled iron than brass/bronze. I'd still get the iron one. It's a LOT of effort to get to the thing!
 
Will it be an issue to install the iron instead of the stock brass that's in there? The Moss catalog states these are NOT interchangeable and MUST be used with their respective gears. I believe I have seen some photos to show differences why you can only use one or the other. I think it had something to do with the type of teeth on the hub/gear.
 
I got mine from VB or an outfit long gone (Special Interest Car Parts). I don't know about the Moss parts, Bob likely has more recent info.
 
Sorry, i'm old school. I replaced a steel syncro in a MGA that was rebuilt by another fellow and it would grind going into 2nd. Not having a good history on it I replaced 2nd gear with a used one and put a new brass 2nd syncro in it. That way I knew I had a combo that would work. Brass syncros last a long time if you just pause a second between gears. Its not just a straight shot from first to second... Bob
 
Thanks for all the help fellas. I am going to order the brass just to eliminate any guesswork. This MG is not going to be driven hard or often, so it should last for quite some time. Merry Xmas guys and thanks again.
 
I'm sure it'll be fine. The scintered iron ring was a BMC "field fix" back-when for replacing the brass one 'cause the brass ones were abused by uninitiated operators. Jag E-Types suffer'd the same condition. A "step-shift" or "stutter shift" eliminates the problem. Actually it's only about a half-second pause in neutral position before going to second, as Bob describes.
 
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