Agree with hofferwood. If your going to use the die to add threads the shoulder (unthreaded area) will need to be turned down. Measure the diameter of shoulder, measure the threads. The die won't cut the larger diameter shoulder down, I believe.
Crank Nose Threads & Thick Washer Question
- Thread starter PurpleBeeper
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PurpleBeeper
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Thanks guys!!! Yep, bottoming tap and an extra 1/2” to work with makes me feel more confident I can fix it. THANK YOU ALL!!!
I use the 1/4" rope method in either #6 or #1 (depends on my mood) to tighten the balancer.
As mentioned if you can tighten it to 135 ft/lbs your worries are over.
As mentioned if you can tighten it to 135 ft/lbs your worries are over.
PurpleBeeper
Well-Known Member
Please tell me what this is. Thanks!
PurpleBeeper
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This makes sense, but I'm thinking I might just add a 2nd washer (?). I have to get the pieces in my hands & measure everything to be sure
hofferwood
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Roll #1 to around to around bdc you want it to be coming up (#1) to compression (both valves closing) pull the spark plug and stuff about a foot or two of 1/4" rope inside the cyl (DON'T LOSE THE END). Then you can torque the bolt--------it stops the motor from turning.
Back it off, and pull the rope out.-----------or leave it in, up to you
Say turn engine so #1 piston is down in the cylinder on intake stroke and when you raise #1 piston on compression to TDC BOTH VALVES ARE CLOSED. Don't want a bent valve! feed 3 or 4 feet of rope into #1 and leave a few feet outside to pull the rope out. Turn engine using damper bolt. Rope will jam and stop engine from turning torque damper bolt.
When I was typing saw another post was added. Figured it was the same answer.Roll #1 to around to around bdc you want it to be coming up (#1) to compression (both valves closing) pull the spark plug and stuff about a foot or two of 1/4" rope inside the cyl (DON'T LOSE THE END). Then you can torque the bolt--------it stops the motor from turning.
Back it off, and pull the rope out.-----------or leave it in, up to you
hofferwood
Well-Known Member
You splain it more better-----When I was typing saw another post was added. Figured it was the same answer.
PurpleBeeper
Well-Known Member
I took some rough measurements on another OEM crankshaft. The hole is about 1-3/4” deep with about the last 1/4” not threaded. Also, the first about 3/16” of the hole is beveled and not threaded. Looking down into the hole to the last unthreaded 1/4”, do I need to drill that to 11/16” first, then finish tapping the hole, or can I just the tap in there as it is? It does look like it sticks up higher than the threads. And if I do have to drill first, how do I drill straight and not screw up the other threads? I’m working on the crank inside the motor in the car, so it’s a little tight to work on there. The OEM 440 bolt sticks out about 1” past the fat washer. If I trim down a small block bolt (2”), I can cut it to stick out 1-1/2” past the fat washer and use the crank hole as is (extra 1/2” thread engagement) or try to drill/tap the entire hole and get 3/4” extra thread engagement on a small block bolt trimmed to 1-3/4”. Thoughts?
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What does the inside of the damaged crank look like? How far down are the threads damaged?
Doug
Doug
PurpleBeeper
Well-Known Member
FIXED! I ended up using a small block bolt & 3 factory thick washers. I ran a 3/4-16 bottoming tap into the hole, cleaned the hole out with carb cleaner and used a liberal amount of red loctite. Worked like a charm
PurpleBeeper
Well-Known Member
First 2 threads trashed inside the crank. The tap pulled out a lot of metal, but it was mainly bolt, not cranks (Thank the Lord). The fix worked great
PurpleBeeper
Well-Known Member
Here is the OEM bolt
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