Crank pulley nut question

smittykid

Senior Member
My 28 pickup has a tool box mounted under the radiator shell thus blocking the crank hole. I purchased one of those 1 3/8 offset wrenches to turn the engine for future timing(if needed) When I went to test fit the wrench on the 1 3/8" nut, I was shocked to see the nut was loose! I have not had any overheating problems. I was on the right side of the truck. The nut would tighten and I could turn the crank nut to the left, but when I pull it toward me, it loosens again. A mechanic told me this is not uncommon and just to tighten it the best I can. I still worries me. Have I got a major problem here or was he right?
 
remove the crank bolt
make sure the end of the crankshaft does not protrude past the crank pulley as you want the bolt to hold the pulley securely.
clean the bolt and crank threads with brake kleen then blow dry
locktite the bolt and reinstall
keep an ear and eye out for leaks or noises from that area...
 
If the threads are worn on the crank bolt then I'd replace it. I've never heard of one stripped, as your's sounds like it is. The pulley is driven by a key in the shaft, so it will turn fine even with a loose bolt, but check the pulley and crank end as Mitch mentioned, and keep a tight bolt in place. If the pulley isn't clamped tight by the bolt it will likely wear to a sloppy fit after years of use. I've never come across a loose or stripped crank bolt.
 
Thanks Mitch & Tom. I'm going to pull the crank bolt out, clean the threads and reinstall with some blue Locktite. I will check the end of the crank as per Mitch. I will report back later.
 
If you put the Truck in high gear with parking brake on you should be able to get the bolt tight with out the engine turning on you.
 
I use a blunt chisel in an air hammer. Just poke it through the spokes on the backside of the pulley, position it in a cranknut slot & BRRRRP-BRRRRP, it's TIGHT! The Dog addresses me as, "cranknut" !
Bill W.
 
Got the bolt out, threads looked pretty good. I cleaned the threads and applied blue Locktite . I haven't tried starting it yet as I want to take it for a spin and it's been raining ever since I replaced the bolt. Thanks to everyone for all your help & suggestions. Smitty
 
Took the old boy out yesterday for a 6 mile jaunt. When I put him back in the garage I checked the crank bolt & it seems to be good and tight. Thanks again to everyone! Smitty:D
 
How do you change the Crankshaft Bolt/Nut?
My early '30 Oval Coupe has a nut that has rounded corners and broken "teeth".

I order a new one from our wonderful parts suppliers.
I plan to torque to 80 ft lbs.

But, I cannot get a wrench on the bolt/nut.

Do I have to loosen and lieft the motor?

Diastole
 
If you can get a 1⅜" socket (preferably a 6 sided socket) on the ratchet nut, use an extension thru the crank hole and an impact wrench to loosen it.

Or do as I (mistakenly) did once, Start the engine after you forget to remove your timing wrench...


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Weld a lever to the nut so that the end rests on the cross member. Hit the starter for a quick second and the nut will be loose. Grind off the welds to remove the lever and then remove the nut with a set of channel locks.

Or use a pipe wrench with the car in high gear and the parking brake set.
 
There are sockets that grab the flats on worn nuts ! not sure if they have larger sockets. I have a set of Metrinch sockets, my other sets of sockets don’t get used !
 
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