Tohatsu 30hp 2 stroke reassembly

I'm new here and I'd be grateful for a simple bit of advice. I've been chasing a problem on a 30hp 2 stroke and after a compression test showed a 30psi difference between the cylinders I decided to open up the engine to investigate.

I'm looking at reassembly and putting the crankshaft back into the crankcase. The manual says "All main bearing knocks (21) are seated against thecrankcase mating flange of the cylinder block for properalignment with the crankcase." I can see the knocks although it's not a term I'm familiar with (Prior to this I wouldn't have wanted a knock in a bearing) and I can align them with the notches in the crankcase. However there is also a pin in the seal that is in the centre of the crankshaft and there is no notch for that. It isn't mentioned in the manual. There are three potential holes that the pin could fit in (2 in the cylinder block and one in the crank cover) . My question is which is the correct hole to use. I am fairly sure I know which was used before as there are some witness marks from the knurling on the seal but that looks to me as though one cylinder would have a greater crankcase volume than the other. I don't know whether this has been taken to bits before so I'd like to confirm the correct position for the pin.

I'm attaching a picture showing the pin I'm talking about. Where does it fit?

Any advice will be gratefully received.

Russell

Never had one of those oldies apart, but the spring pin just keeps the labyrinth packing from spinning. I would engage it in the block.

Hi Paul

Thanks. That's what I did.

I had another look at it with a friend and we concluded I must have it right because the other holes were larger than they need to be to locate the pin in the seal. However it is very difficult to assemble because the hole and pin are both under the crankshaft when you are trying to locate them.

Russell