Thread: Series 2a gearbox ID

Originally Posted by Land-lord

Hi.

Can anyone advise how I can identify a s2a gearbox please?

Differences between the 2 and 1 - when compared to the 2a?

THanks

There were progressive changes that did not occur at either the change 1 to 2 or 2 to 2a, so there is no real answer to your question. The key is the gearbox number suffix, and there are significant changes with each of these changes. All of the changes seem to have been improvements, so you would want to look for the highest letter you can find!

John

John,

How do I locate the gearbox serial # from above or below?

The gbox is currently hooked up to engine in normal position.

What numbers indicate a 2a box?

THanks

Originally Posted by Land-lord

John,

How do I locate the gearbox serial # from above or below?

The gbox is currently hooked up to engine in normal position.

What numbers indicate a 2a box?

THanks

To see the gearbox number you will need to remove the transmission tunnel cover, although you might manage with a mirror from below if it is clean. A 2a box is any one with a letter suffix to the number.

John

Thanks Jd.

I have now located the gbox number - thanks.

It reads "90..... A"

Is this a series 2a or 3?

THe reason I ask, because most of the s2a boxes I see being referred to start with "2"..

ANy help appreciated..

Originally Posted by Land-lord

Thanks Jd.

I have now located the gbox number - thanks.

It reads "90..... A"

Is this a series 2a or 3?

THe reason I ask, because most of the s2a boxes I see being referred to start with "2"..

ANy help appreciated..

I can't find a reference to the actual numbers, but I know the S3 boxes started the letters again, in other words, start from A, but according to my reference the S3 boxes usually have the number on the actual transfer case not the gearbox, on the sloping bit of the flange that joins to the gearbox, with the number running down rather than horizontally and on the gearbox itself. (The use of the word "usually" suggests this may not be quite definitive)

However, unless the front cover and bell housing has been swapped (which is possible) it is easy to tell a S3 box from an S1,2,2a box - the S3 has the clutch slave cylinder on the left side and operating directly on the fork, where the S1,2,2a has the slave cylinder on a bracket on the right side, operating a cross shaft that in turn operates the fork.

John

box number = 90141780 A

Can you confirm now?

Did the S3 transfer case also have a 41mm int. shaft?

Number is horizontal..

what number range did the s3 gbox start from and what series number range did the s2a end?

is this blister you mentioned before cast into bell housing? If it is then I can see soemthing poking out LHS cast into housing...

Originally Posted by Land-lord

Number is horizontal..

what number range did the s3 gbox start from and what series number range did the s2a end?

is this blister you mentioned before cast into bell housing? If it is then I can see soemthing poking out LHS cast into housing...

I can't tell you what the number sequences are - they are not given in the parts books, generally only talks about the letter suffix, although the S3 parts book does give a couple of numbers, showing that there are at least two sequences for the S3 box, one starting with 36, the other with 90. I have not found any indication of numbers in the S2a parts book, but I think all the boxes I have start with 2 - but that doesn't mean there are not other sequences.

The attached picture shows the distinctive mount for the slave cylinder on the S3 box - this does not exist on the S2a box, but instead has a hole in the bell housing on the opposite side through which is a shaft from the slave cylinder to the release mechanism.

John