172 timing issues

[Icemanian99]

Good evening chaps. Hope all is well?
Wondering if any 1 could help please?
I am having problems with the timing on my 172 51 plate. Timed up the cams ok with the bar but it's just the crank I am having trouble with....
Tdc the silver smaller pin will go into the location hole through the block but the bigger pin will only go in and screw into the hole when on the down stroke of the piston . The fly wheel is locked when using the smaller pin but will turn when using the bigger pin. There is a cut out on the crank at 1 o'clock which auto data says to use but that isn't tdc and the larger pin fits in but doesn't lock the crank grrrr!!!! Confused
Cheers Ian

 

[bloke]

screw in pin is for the k4m engine.

 

[bloke]

also the autodata guide is wrong, can't remember what part but it's wrong anyway.

 

[Icemanian99]

also the autodata guide is wrong, can't remember what part but it's wrong anyway.

Time the crank up tdc with the smaller pin? Don't think it's the k4m engine. How would I find out? Thanking you for your help kind sir

 

[bloke]

it's the f4r, slip in pin. make sure it'sin the locking hole not the balance drilling that's right next to it.

 

[barnesautos]

There's a mark on the flywheel , you need to get the mark inline with zero mark on the gearbox . Only then "you" will know it's spot on.
You did well to be cautious.

TDC mark is to the left of the crank position sensor , has its own window.