Crank pulley bolt needs torqued to 200 ft lbs, and medium loc-tite is a good idea.
Highly recommend renting a torque wrench if you don't have one that goes that high.
If the bolt backs out, it'll cause more problems.
Hard to hold pulley in place to torque with oil pan on too.
Needs a block of wood between a crank journal and the block to keep it from turning.

 

+1, YES get a torque wrench!!! And re: the crankshaft seal
ERR6490 get a CORTECO > RovahFarm for all your new Land Rover Parts and Accessories I think L8 sells this brand too. > https://www.lucky8llc.com/

IF you want to buy a T wrench (the price is way right) try a TEKTON.
For giggles I had a NEW one tested/calibrated along with my Snap-On QD3R250A ($350.00) > https://store.snapon.com/US-Torque-I...--P874542.aspx and was shocked at how accurate it was.

Now I am NOT saying this T wrench is 100% on par with Snap-On quality, but for $59.00 it works very well.
> https://www.tekton.com/1-2-inch-driv...e-wrench-24340

 

Or move the breaker bar/pipe to the other frame rail & bump the starter again. There is a bit more stuff in the way like the steering box and arm, but a few blocks of wood, and a bump of the starter and you’re back in business. Also 200LB torque is recommended, but the engine is spinning in the direction of the bolt tightening so technically it shouldn’t just fall out/off you don’t get it to 200LB of torque. I know I certainly don’t put my clutch fans back on as tight as they were from the factory & I’ve never had one fly off.

 

I would agree with you, but I have seen it happen.
I had an 01 4Runner, 3.4V6
Replaced timing belt (super easy job).
Crank bolt needed 150'lbs.
I tightened it with a 1/2" drive breaker bar, and prybar in flexplate teeth. I got it tight too. But, I got side tracked and forgot to torque it(I always use torque wrenches).
Drove it 2-3 days, heard a knock, opened hood with it running, crank pulley was wobbling.
The bolt had backed almost completely out, and managed to somehow bugger the threads in the crank.
My Dad was able to fix it properly, but it was a
careless mistake I will not make again.
If you ever need to see some impossible sh*t break on a car, just call me. My mere presence overwhelms them and gremlins show up and wreak havoc, lol.

 

Yep I agree anything is possible.

 

Just a smidgen of blue locktite will help keep the crank bolt where it belongs....once properly tighten.

EDIT: I usually clean up the crank surface with a piece of 200 grit crocus/emery cloth before installation, and if you can see/feel a groove on the crank surface...sometimes I'll try to position the seal in a different location, in or out, if allow-able...to get seal mating surface on a fresh surface of the crank shaft. Sometimes just being left out farther a mm or two, or in, can make all the difference in the world. Usually, the seal will only go in so far...and that's the position they used at factory.

Brian.