So I change my heater core, fairly simple process... but on the top hose I used a cap from a hair spray bottle to keep fluid from spilling everywhere . I forgot about the stupid cap and after changing heater core attached hoses back to core forgetting about cap... effectively plugging off hose. I then ran the car for a few minutes checking for leaks in the hose then shut it off. I didn’t drive the car any where.... An hour later realized the stupid blunder I made, pulled the hose clamp off, removed the plug and reconnected. I started the car and it seems to run fine. I haven’t driven it anywhere. I’m not a mechanic, but did I royally screw anything up by running the motor with a plugged hose for 3-5min?
Min

Read This post, and check that your thermostat doesn't now look like this...

Thanks Patrick, thermostat was fine, think I got lucky. Fiero running well!

quote Originally posted by branger: ...thermostat was fine, think I got lucky.

Yeah, it probably would've taken more than a few minutes of running to have possibly done any damage.

quote Originally posted by branger: I then ran the car for a few minutes...

Thanks Patrick, thermostat was fine, think I got lucky. Fiero running well!

The Water Pump will get very high loads trying pump like this.
See my Cave, Heater
Bent Tstant is only one part that may fail for blocked heater loop.
If you have a plastic impeller then can easily damage the pump and cause low/no flow and overheating.
The Alt and WP belt doesn't like this and even w/o making noise can damage the belt same as either having bad bearings or slipping belt. See my Cave, Serpent Belt

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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

I think that a centrifugal pump has the hydrodynamic advantage of variable valving of the outflow regardless of the impeller speed.
If the outlet valve is closed, the impeller just spins the fluid around inside the housing. No relief flow is necessary.
As the outlet valve opens, some fluid exits the outlet until full flow is achieved at full open valve.

My 1929 Ford Model A has no heater circuit; a common design in the era.
When the thermostat is closed, the impeller spins coolant around in the water pump cavity.

Thanks for the feedback... I think I got lucky, as the thermostat is not bent and it blows heat well, so hopefully the water pump and impeller are also fine.