Resolved: 1963 75hp Flywheel Nut Tightening

[yorab]

Hello. I need to tighten down my flywheel nut to spec which is 70-85 ft-lbs. When I removed it, I used a box end wrench. I put a couple of grade 8 bolts into the threaded holes and wedged a heavy prybar between those bolts while I used the wrench to loosen the nut. Now I need to replace the nut. I can't use the threaded holes because I now need to use a torque wrench and a socket. The socket gets in the way.

I have a strap wrench but it isn't big enough. I tried to use a ratchet strap around the flywheel to keep it from turning while I tightened the nut, but I couldn't get the torque up to spec. The strap kept slipping. I'm thinking of getting a spanner wrench from Sears tomorrow since there is a Sears just up the road. Would a spanner wrench work in those holes in the side of the flywheel? Here's a link to one of their spanner wrenches:

http://www.sears.com/shc/s/p_10153_12605_SPM223959438P?prdNo=5&blockNo=5&blockType=G5

 

[yorab]

Re: 1963 75hp Flywheel Nut Tightening

Re: 1963 75hp Flywheel Nut Tightening

Here's the flywheel with and without the socket:

 

[dew2]

Re: 1963 75hp Flywheel Nut Tightening

Re: 1963 75hp Flywheel Nut Tightening

I sometomes use a leather belt wraped around the flywheel and clamped with a visegrips,Then use the visegrips as you would a strapwrench handle for leverage and keeping the leather tight.

 

[AlTn]

Re: 1963 75hp Flywheel Nut Tightening

Re: 1963 75hp Flywheel Nut Tightening

Yo..google...matco tools flywheel turner..someone posted a pic and link to one that looked like this,but was cheaper...

 

[yorab]

Re: 1963 75hp Flywheel Nut Tightening

Re: 1963 75hp Flywheel Nut Tightening

I did a bit more research on the topic and it looks like people have used the ratchet strap with success. They wrapped it around the flywheel gear 2-3 times whereas I only wrapped it once. I'll try to wrap it more and see what happens. If not, I'll try to hunt down that flywheel turner. I just need to get something working today, so I'm not sure how successful I'll be at finding the turner on a Sunday.

 

[Cofe]

Re: 1963 75hp Flywheel Nut Tightening

Re: 1963 75hp Flywheel Nut Tightening

I use a old automotive serpentine belt with a pair of vise grips.

 

[lindy46]

Re: 1963 75hp Flywheel Nut Tightening

Re: 1963 75hp Flywheel Nut Tightening

Nylon ratchet strap works great.

 

[Chris1956]

Re: 1963 75hp Flywheel Nut Tightening

Re: 1963 75hp Flywheel Nut Tightening

I used a heavy square shank screwdriver between the ring gear and the block. There was a casting that held the tip of the driver and the ring gear grabbed the shank.

BTW - isn't that nut supposed to be tighter than that? I thought more like 105 ftlbs. Make sure you have it right, or it will shear the woodruff key, and can damage the crank and flywheel.

 

[yorab]

Re: 1963 75hp Flywheel Nut Tightening

Re: 1963 75hp Flywheel Nut Tightening

Success! I wrapped the strap around 3 turns and it didn't slip. It was pretty easy when the strap wasn't slipping. I was able to easily tighten to spec. I double checked the spec for my motor and the OMC service manual says 70-85 ft-lbs. I tightened to 80 ft-lbs. Thanks for the advice.