Thanks for your offer to help, but I have solved the problem and boy am I confused. First vehicle I have ever seen that would not overheat with the water pump completely dead.
New water pump is installed and heating like a big dog.
For those reading here is the blow by blow:
1. Flushed out the old heater core that was removed.
2. Actually it was just fine.
3. Disconnected both hoses at the firewall.
4. Connected the hoses to the old core laying on the fender of the truck.
5. Started the motor and at 200 degrees on the intrument cluster. Zero zilch heat on the hoses or on the heater core. Okdokye I am on a roll now.
6. Remove radiator cap. After engine shutdown.
7. Disconnect both hoses from core.
8. Use water hose and flush water into hose 1.
9. Success. Water flows out the radiator cap.
10. Force water down the hose connected to top of water pump.
11. Success 2. Water flows from the cap again.
12. Fill radiator to brim and start motor.
13. Water flowing from either hose. Whopping Zero.
14. Now here is a 1/2 inch hose connected direct to the top of the water pump and zero water flow.
15. Hell even the slighest rotation of the vane of the water pump should have blown water all over the place.
16. I would never have suspected this as I have never seen a motor run with a completely dead water pump and run below 200 degrees. A first for me.
17. Change water pump. Heats like a big dog.
Has anyone ever seen this. Hell there was not thermostat so I put a new one there also. And a new serpentine belt to make it all look pretty.
If someone had said water pump while the engine was cooling just fine, I would have said Bull.
Hopefully this will help some other soul out there in the future.
Now the darn horn does not work. Must have broken a wire during the major dash rip off to replace the non bad heater core. Anyone need a good use heater core. Actually the removed unit looks relatively new. I suspect someone had replaced in the past trying to fix the heater problem with no success. So both cores are good now.
So no longer will I automatically suspect a leaking heater core when the core has been bypassed or capped off as this one was.
Thanks for the help. But I just saw your input tonight.
One final note: I purchased the one month access to the data on this truck so I guess I will not look up the schematics and parts lay out and get to work on the darn horn. Hopefully some of you nice folks will read this and comment. That will give me an email reminder that a comment has been made and I will return to tell you which wire I pinched or broke during the dash removal for the core change that I did not need. Oh well. Its done. Almost once I figure out this freaking horn thingy.
Thursday, November 22nd, 2018 AT 8:22 AM