Torque spec for flywheel bolt on Yamaha 28A outboard

[ar1g3]

Does anyone know to what torque I should torque the flywheel bolt on my Yamaha 28A?

I think it'll be the same for a 25A and a 30A since they're pretty much identical. I can only find an owners manual, not a service manual, and there aren't any torque specs in it.

 

[pvb]

Probably around 75Nm.

 

[ar1g3]

Thanks! I'll put some thread locking compound on just to make sure

 

[VicS]

Thanks! I'll put some thread locking compound on just to make sure

The important thing is not so much to lock the nut but to ensure that the flywheel is tight on the taper so that it is driven by the taper not the key. The key is only for location . If the flywheel is not torqued down properly and it moves on the taper you can shear the key and damage the keyway in both the shaft and the flywheel.

If you cannot find the correct torque ask on one of the outboard engine forums such as iBoats https://forums.iboats.com/forum/engine-repair-and-maintenance/yamaha-suzuki-outboards

 

[ar1g3]

But will 75Nm be enough to secure it on the taper? I guess so, I losely put the nut on there before and now I took the flywheel off again to oil the ignition cam wipers and I had to use a puller to get it off. So 75Nm plus thread locking compound to prevent the nut from coming loose should do the trick, no?

 

[RichardS]

But will 75Nm be enough to secure it on the taper? I guess so, I losely put the nut on there before and now I took the flywheel off again to oil the ignition cam wipers and I had to use a puller to get it off. So 75Nm plus thread locking compound to prevent the nut from coming loose should do the trick, no?

75Nm is very tight and typically of the order used for critical brake calipers on cars so, in the absence of knowing the manufacturers recommendation, I would suggest will be fine.

Richard