Size of conrod bearing

[janstolp]

I need new bearings for the conrod for a 1098 cc engine.
Problem is I don't know what size I need to order.
On the shell is marked inside a circle: AL ,another circle with the letter:G and the letters DM
Underneath is the number
12A 630
Can anyone shine a light on these numbers?
Best regards
Jan

[smithskids]

Best to borrow a 0-2" outside micrometer.

[IslipMinor]

Jan,

The correct part number for the big-end shells is 8G2198 for standard diameter shells and /10, /20 etc. for the undersize journals. The shells are common to 948 & 1098 engines in Minor, A35, A40, Mini, Sprite Midget etc.

The safest way to know what you need is to measure the big-end journals - the standard size is 1.625", and the undersizes are -0.010" down to -0.040" (-0.060" is also possible I believe?). The equivalent metric dimensions are 41.28mm standard, then 41.02mm, 40.77mm, 40.51mm and 40.26mm.

[janstolp]

Thank you both for your reactions.I think it is the only safe way to measure the journals.
Luckily there is one in the village who can help me because I don't have one.
regards
Jan

[philthehill]

If the crankshaft bearing is undersize the undersize will be marked on the rear of the bearing i.e. 0.030
If there is no additional number to the part number I would suggest that the bearing/shell/journal is standard.