Yanmar 3YM30 valve clearance adjustment

[PTB]

In the service manual section on checking valve clearances it says ' the crankshaft shall be turned clockwise as seen from the gear case side'. The normal engine rotation, I'm pretty sure, is counterclockwise from drive end, which, unless I'm being stupid, is clockwise when looking aft at the engine from the cabin. So, does one turn the crank backwards to check valve clearances ? Not good on impellor for instance? Thanks Phil

 

[earlybird]

Doesn't it mean the timing gear case at the front of the engine?

 

[RichardS]

Doesn't it mean the timing gear case at the front of the engine?

I'm sure that is right. It would say "gearbox" or "drive shaft" if it meant that.

Richard

 

[VicS]

In the service manual section on checking valve clearances it says ' the crankshaft shall be turned clockwise as seen from the gear case side'. The normal engine rotation, I'm pretty sure, is counterclockwise from drive end, which, unless I'm being stupid, is clockwise when looking aft at the engine from the cabin. So, does one turn the crank backwards to check valve clearances ? Not good on impellor for instance? Thanks Phil

If I had not checked the manuals for myself I would have said you'd got it wrong........... but that is what the manual says!

It wont worry the pump impeller. If the vanes flip over they will flip back again

Puzzled though. If RichardS comes this way he will explain. He is the Yanmar man hereabouts

EDIT I see he already has

 

[Laysula]

The reason for turning a diesel engine backwards is to ensure that it doesn't accidentally start. If you turn it forwards make sure that the engine stop is pulled out.

 

[VicS]

I'm sure that is right. It would say "gearbox" or "drive shaft" if it meant that.

Richard

Yes. When they mean the ( transmission) gear box they call it the " gear box" but they refer to the timing gear case as the "gear case"

diagram attached is snipped from the service manual

 

[PTB]

Thanks all ... problem solved !! P