Problems with temperature and Gauge?

[mick8703]

My temp gauge was going up and down.When the temp was up I had no heat,when it came back down-heat.Anyways I changed the thermostat and flushed the cooling system.That took care of the bouncing gauge.Here's the thing tho...While I was running it with flush stuff and water,I had toasty heat.Drained it,filled it 50/50 and burped it.The heat is barely luke warm.What's up?Any ideas?
Mick

 

[TPLYNCH]

The flush may have deposited some stuff in the heater core. Try flushing the core by itself and see if it makes a difference.

 

[smiley1]

Make sure you dont have any air trapped in the system.

 

[nascar_intimid]

I would say it needs to be burped more...always fill the rad with the truck running!!!
good luck

 

[TheRookie]

The ford shop manual ( I know this book well) for the sploder says specificaly the heater core will need to be backflushed in the event of a coolant flush. Take BOTH heater hoses off the core and put a hose to them. I did this back and forth till water flowed freely between the 2. You will be amazed and or disgusted with how much crap can come out

 

[nascar_intimid]

thanks for the great advice on backflushing...

 

[mick8703]

I'll try flushing the core.I was kinda thinking that might be it.I did reburp it and always do fill with the truck running,but thanks for the tip anyways.Worst case I guess I'll try replacing the core.
Mick