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MG MGB Technical - Flywheel Balance

As part of my 3-sync to 4-sync transmission swap, I'll be replacing the engine backplate and flywheel. Are there typically balance marks on the flywheel and crankshaft that should be matched up? Thanks. -G.
Glenn G

Not "balance marks" as such, but there is a 1/4 mark on the OD which should line up with the crank throws for those cylinders, IE straight up at TDC, Crank should also be marked to match. At some point these may have been deleted, or some engines may have dowel pins that restrict flywheel positioning. Can't remember.

FRM
FR Millmore

Just to avoid confusion, I believe when FRM says "OD" he means Outside Diameter rather than overdrive.

Charley
C R Huff

No, no balance marks - early flywheels go in one of two positions on the crank - as FRM says the TDC mark on the flywheel is 1/4.

Out of the factory both cranks and flywheels were only roughly balanced.

It is very rare for the crank and flywheel to be balanced as a unit - normally the crank is balanced first and then the flywheel added and balanced.
Chris at Octarine Services

Thank you for the comments. I found the 1/4 mark on the edge of the flywheel and made sure it was on top with pistons 1 and 4 at TDC. -G.
Glenn G

This thread was discussed between 28/03/2012 and 04/04/2012

MG MGB Technical index

This thread is from the archive. The Live MG MGB Technical BBS is active now.