hi all,i just removed the flywheel of my 740 turbo 1990 and i somehow forgot to mark its position.I know this plays a factor because the sensor that is there is used to control the ignition and that the positin of the flywheel makes a difference.My engine is out so i turned it to the TDC and i was wondering if anyone knows how i should place it back in at that point.Thanks

This is already covered in the 700/900 FAQ, click here to go to that section of the FAQ. The picture was taken in my garage, and the engine is at number 1 TDC.

The text from Swedishbricks is:
"Turn the engine to #1 TDC (timing marks in line on crank pulley to pointer on timing belt cover), then install the flywheel so that the two rivet-like pins that are on flywheel inboard of ring gear about 1+ inch are on the exhaust side of block roughly at 2 o'clock and 3:30 while the engine is at TDC. You might find that at this position you will see a faintly stamped arrow pointing at the crank sensor. Not all flywheels had this arrow for the first couple of years, so you might not find it on yours. One bolt hole in either direction puts them way out of this orientation. The spot on edge of flywheel where the holed surface is interrupted will be mostly lined up with starter when it is correct. "

I think you have to assume that you're looking at the flywheel end of the engine here, ie looking forward. That way the exhaust side would be on the right, and "2:00 and 3:30" would be roughly over by the exhaust manifold.
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Rob Bareiss, New London CT ::: '86 244DL- 215K, 87 244DL- 230K, 88 744GLE- 198K, 91 244 180K

The odd hole (closed) should be at 90° BEFORE TDC. When you are facing the back of the block and the crank is at TDC, the non-hole should be at 9:00, near the starter opening.

Solved thanks to swedishbricks.com


http://www.swedishbricks.com/700900FAQ/Engine-Mechanical1.html#Flywheel%20Position%20on%20Re-installation

Beware the confusing text provided in that posting. It doesn't say which way you should be viewing the engine when it refers to 2:00 and 3:30.

Look at the Engine-Mecanical section in the BrickBoard 700_900_FAQs and you'll see a photo posted. The closed hole goes where I said...by the starter opening. I had forgotten about the pins, one of which is visible through the starter opening at TDC.

If this were for an enigine getting a new rear main seal and the front was together, I'd also add that camshaft position has no effect on flywheel placement so you don't need to remove the timing belt cover to peek at the marks.

Thanks for your help everyone