I drive an 82 F100 with a 302 in it, and ran into some trouble trying to drain my coolant system in order to remove the intake manifold to replace those gaskets due to a suspected vacuum leak there. ANYHOW, after draining the coolant out of the radiator I went to go drain it from the engine block itself. In my Hayne's manual it said that on V8s that the coolant bolt on the passenger side of the engine would be hidden by the starter. After removing the starter however, I found no such bolt (only a threaded hole, only about an inch or less deep before running into some metal at the back) where I suspected the coolant bolt to be. On the driver side of the engine I found a bolt threaded on the outside with a hex fitting in the middle, that bolt is stuck but I've yet to try any rust remover on it.

My main concern is the bolt that should've been behind the starter and the lack thereof, because if I cannot drain the coolant I do not know what to do. It is also hard for me to even tell what is going on with that hole, and whether the hole was built that way or an old bolt was snapped off almost an inch back into the opening, or if I'm even looking at the right bolt hole to begin with. Attached are some photos, the ones with blue markings on them are from the passenger side where the starter was with the missing bolt, and the ones with orange markings are from the driver's side of the engine that just has the stuck bolt.

Any ideas regarding how the passenger side bolt hole got to be how it is, or ideas regarding how to go on from here if I'm trying to remove the intake manifold but cannot drain the engine block of coolant.

 

The passenger side coolant plug is actually closer to the front of the engine, and you don't have to remove the starter to get to it. It should also have a pipe plug in it, like the driver's side. Sometimes the hole could be plugged up with crud, and no coolant will drain out even after removing the plug. You have to go digging into it with a screwdriver to clear up the crud.

Be careful trying to remove the plugs. Make sure your allen wrench fits correctly into the hex hole before you start torquing. The driver's side plug on mine is hard to get to, and I think the previous owner stripped out the hole, so I've never been able to remove it. If I ever remove the engine again, I will have to drill out the old plug.

Not sure that the empty hole is on your block.

 

That's a blind hole, ignore it. Those allen plugs ? I've never been able to remove one. No need to anyway. What ever coolant gets spilled into the engine will be taken care of by doing an oil change after you're done and should always be done to remove whatever trash gets in the crankcase in doing the gaskets replacement. The rest in the lifter valley ? Paper towels.

 

There is an alternative way to drain if the plugs are stripped/frozen/whatever.

Pull one lower side head bolt an siphon coolant.