Total Rebuild of a 1979 Dodge Class C

About fuel pump, I would first get a new mechanical pump as a leak internally could flood the crankcase and do much damage. I have electric pumps on each tank in addition to mechanical one, My grandson playing radio had ignition on and also turned on rear elec. pump which filled the crankcase so when I tried to start it it sounded like maybe the timing chain had slipped. I would start and run for a few seconds then stop. I messed with timing, changed distributors and in the process broke three starter cases at which point I pulled the timing chain and although it wasn't warn I replaced it. Also found the front seal around the V. damper was cracked open, the rubber part, That led me to believe the problem was old but the ecectric pumps, I only use before starting or climbing steep long hills which might cause vapor lock, the overfilled oil wasn't obvious but did rupture the front seal that allowed eccess to leak out until the time my grandson had it filled and thinned with fuel so it didn't run.
After new timing chain, front seal and replaced mechanical, I still use elec. pump the same way but no more problems.
Mickey