Flywheel Markings

[Scooter]

Hi,

The flywheel on my BN4 has one major timing mark with two smaller timing marks on either side. I know the center mark represents TDC, but I'm not quite sure what degree location the other two represent. All of the flywheel images shown in my workshop manuals show only mark (TDC), but not all three. Would these other two marks represent 6 degrees either way?

Thanks,

Scooter

 

[John Turney]

Scooter,

If your engine has been previously rebuilt, those marks were probably put there by the (a) previous rebuilder. I didn't notice any on mine, but I have a 3000 engine.

John, BN4

 

[Dave Russell]

Scooter,

See if this thread will help.
https://www.britishcarforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=1&t=000526

I don't know the exact outside diameter of your front pulley but this will give you the values for any pulley.

Assume a pulley diameter of 6". (Use your actual diameter. )

multiply 6" by 3.14 to get the pulley circumference, = 18.84"

Divide 360 degrees by the circumference of 18.84" = 19.11 degrees per inch of circumference

Measure the distance between your pulley marks. Assume .5 inch between marks. (Use your actual distance.)

Multiply the distance between marks by the previous 19.11 degrees per inch.
.5 inches times 19.11 degrees per inch = 9.6 degrees between the marks.

You can calculate any mark distance & put marks on your pulley anywhere that you want them.

Addendum: I guess that I can't read so well. Just realized that you were asking about flywheel, not pulley. The same principles apply except it is harder to find the flywheel diameter. Sorry!
D

[ 06-03-2003: Message edited by: Dave Russell ]</p>