1970 GT 1.9 Timing marks

[Brohate]

Can some one tell me where the timing marks (pins) are on a 1.9 '70 GT? Maybe I'm blind but couldn't find them and the manuals don't seem to be much help. Thanks.

[markandson]

Cam timing can only be seen with the timing chain cover off. TDC on the flywheel is seen through a hole in the left side of the bell housing, where there is also a pointer. There is also a set of marks on the timing chain cover in line with the distributor shaft, and a mark on the crank pulley. The last set of marks mentioned is where you would use a timing light to determine spark advance.

[kwilford]

Originally Posted by markandson ... and a mark on the crank pulley.

Not on any factory Opel GT 1.9 CIH crank pulley from 1969 to 1973 that I have ever seen. Smart folks cut a groove in the pulley at TDC and paint it white so the timing marks on "most" CIH timing chain (but not all) cases can be used against the TDC mark. Virtually all factory GT's are timed using the pointer on the engine back plate and the ball embedded in the flywheel. You have to point the timing light under the intake manifold towards the rear of the engine and look for the oblong hole in the rear engine plate, which is where the pointer is. See the attached FSM photo (or look at your own FSM, or buy one )