As title ( not quite but it got you to look)

I've just snapped the lower rear rocker cover bolt after replacing all the seals.
It has snapped off inside the block.
From the searches I've done the proper way would be to remove the engine and try to remove the rest of the bolt.

I need to run the car though so would the bolt hole stay sealed temorarily with gasket sealent or would it get pushed out with the oil/ pressure?

Any help would be appreciated.

 

Is the rocker cover hole open? It might hold with just sealer but it would be a better idea to find a bung of some sort and secure this in with sealer. You could try a larger diameter bolt to get a couple of threads into the cover it' self to block it of.

 

I had one go at the top rear of my o/s rocker cover. Luckily it's not sitting in oil the whole time and silicone sealant was enough, with the broken bolt in place acting as a bung rather than for any mechanical strength.

As long as your other 5 are OK and you can get them to tighten down you should get away with high temp silicone sealant under the bolt head to make a good seal against the oil. It's only ever going to be a temporary repair though. As you rightly suggest it's engine out time really if you want to fix it.