I broke in my newly rebuilt 340 last week with no problems, and did not run it again until tonight. I broke it in with no thermostat installed, but replaced it afterwards.

Tonight I shut the motor down after a few minutes of running, and shortly after shutting it off I noticed a hissing noise and steam coming from rear passenger side exhaust manifold. Coolant appears to be coming from around the second bolt from rear on passenger side, or the bolt just to the right of the rear outer stud.

Is this bolt exposed to the water jacket?

All four outer studs were sealed with Rector-seal so I don't think it's coming from there, but I don't believe any of the other bolts were. I am hoping that all I have to do is drain the fluid down and reseal all bolts. Do all small-block exhaust bolts contact the water jacket? Also, it seems that water only leaks after engine is shut off and pressure builds...

Any thoughts on this?

Thanks!

Brian