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Harmonic Balancer / pully nut

bobbo

bobbo

Donation Time
Will be installing the Harmonic balancer back to the engine, but need to know the best way to get the tapered nut tight. what size socket should I use? Have been tapping a 1-1/4 socket on snug, but it just not quite the right fit. I was able to remove the nut with the 1-1/4 socket, but I don't think it's the right tool to assemble.
Thanks Bob
 
bobbo said:
Will be installing the Harmonic balancer back to the engine, but need to know the best way to get the tapered nut tight. what size socket should I use? Have been tapping a 1-1/4 socket on snug, but it just not quite the right fit. I was able to remove the nut with the 1-1/4 socket, but I don't think it's the right tool to assemble.
Thanks Bob
Click to expand...
Balancer (crank) bolts are 1 5/16".
 
From one of my previous posts:

The pipe-style starting nuts can be torqued with a 1-5/16" deep socket... PROTO Tools makes the proper item:

PROTO 1-5⁄16" size … 29 / 32" deep … 3/4" drive … Proto #5542

It can be found from many suppliers… here’s one:

https://www.amazon.com/Stanley-Proto-J5542-4-Inch-16-Inch/dp/B00018AJSY

I'm almost certain nobody else makes a socket with the sufficient depth... I did a *lot* of research to find this Proto item, and I've actually used it for the job, so it's a sure thing.
 
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Again (how many times I mentioned this) throw that hand crank pulley bolt away and get serious with using a grade 8, 1" length 3/4" dia. bolt, and tighten it to 100lb-ft. Then the harmonic pulley is tight on the crankshaft.
Jan
 
jumpinjan said:
Again (how many times I mentioned this) throw that hand crank pulley bolt away and get serious with using a grade 8, 1" length 3/4" dia. bolt, and tighten it to 100lb-ft. Then the harmonic pulley is tight on the crankshaft.
Jan
Click to expand...

I did just that after losing the original bolt and crank pully while driving. Much better replacing the bolt then losing the pully and replacing it with another $200+ pully.
 
jumpinjan said:
Again (how many times I mentioned this) throw that hand crank pulley bolt away and get serious with using a grade 8, 1" length 3/4" dia. bolt, and tighten it to 100lb-ft. Then the harmonic pulley is tight on the crankshaft.
Jan
Click to expand...
Hmm. I’m curious, Jan… have you seen actual failures of the starting nut resulting in damage or loss of the harmonic balancer? I had a starting nut on my car from new and it was a real bugger to get off. I reinstalled it when I rebuilt my engine (after balancing it along with the crank, etc.) and it seems to be holding fine.
 
Examples of the crank nut loosening are numerous. Whether the nut loosens first or the balancer develops a crack in the keyway first I don't know. Regardless, the nut can completely back off, allowing the balancer to exit as well. If you're lucky, the balancer won't bugger up the end of the crankshaft as it departs.

After my balancer cracked a couple of decades ago, I put an SS balancer on, with the crank nut and tightened the heck out of it. No problems since.

Just a note on the nut size. The reason a 1-1/4 socket is too tight and a 1-5/16's is a little loose is that its a Whitworth size.
 
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puff4 said:
Hmm. I’m curious, Jan… have you seen actual failures of the starting nut resulting in damage or loss of the harmonic balancer?
Click to expand...
Oh absolutely, I find the key way cracked (and sometimes damage to the crank key & grove). Some of the engines I rebuild (probably most of them) do NOT have the hand-crank-pulley-bolt tight enough. It needs the proper 8-grade bolt to tighten to 100 lb-ft....Why? That pulley, that people call the "harmonic balancer", isn't a correct name for it, what it does is a torsional absorber, or torsional damper. Those names aren't quit right either, but it does "dampen" the torsional vibrations in the crankshaft to some extent. It needs a firm grip on the crankshaft.
Jan
 
Seem to have a little damage on one of the threads on my bolt. So I'll take Jan's advice and go for a gr. 8 bolt 1 inch. Just a question on the thread of that.
If the original is Whitworth, do they have a different thread?
 
Jan - how do you keep the engine from turning when you are putting 100 lb-ft of torque on that bolt?
 
Put the transmission in 1st gear, apply the emergency brake, block the rear wheels. if it still moves the car, have someone press on the brake pedal.
Otherwise, you can take the dust cover off of the bell housing and block the flywheel teeth to prevent the engine turning while you torque the bolt.
 
bobbo said:
Seem to have a little damage on one of the threads on my bolt. So I'll take Jan's advice and go for a gr. 8 bolt 1 inch. Just a question on the thread of that.
If the original is Whitworth, do they have a different thread?
Click to expand...

The nut size is Whitworth. Don't know about the thread.
 
If the nut size is Whitworth, one could only imagine the thread is also Whitworth. Checking with Mr. Google, Whitworth threads are cut at 55 degrees and radiused top and bottom.
Different than what is standard today.
Maybe just clean up the one damaged thread and put it back, especially now I have the 1-5/16 socket.
 
Back in the 70's when I owned my first 65 Series IV (early), that crazy Hand Crack starter nut on the front of the crankshaft used to come loose routinely. When Loose and floppy a bit, it would "ring" and was audible when driving the car. Come to a stop at a light, and it would rattle and ring and I could hear it. The Pulley/Dampener itself never came loose but that nut would.
 
Two questions that I hope aren't too dumb:
I have not seen otherwise but is the thread right hand? (Right to tighten) Just checking...
Is it acceptable to remove the nut with an air wrench? (Not tighten, just remove)
 
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