duster75

Well it all started last week my fan decided to shear off at the nut, taking radiator out and shroud. Its been cold and I had no choice but to run her 12 miles to home never got over 200 on guage. Put new radiator in and now have no heat, have tried everything I can think of to get air out, parked on hill nose up /down ect. did not know about bleeder screw in head till after running several miles.Blend door is working. So I ordered the "golden cummin's thermostat" from scheids will put it in tonight and check old one out on stove. Cannot belive the $97 price, its not like a "normal" everyday gas thermostats but $97 WOW. The truck will actually produce more heat switched to AC and the temp dial on hot.

Dieselbuilder

Undo the lines to your heater core then turn the heat on full and push water through with a hose one way then the other most of the time its ether air locker or the core has built up sludge in it and the garden hose should free it up

SIXSLUG

Ford owns "cummings"....

duster75

Well glad we have spellcheck here. Anyway put new stat in and no heat still.can't believe core would be plugged since before above happened she'd boil you out of cab.Guess flushing will be next move. Going to be in 30's next couple days.

Busboy

Before flushing make absolutely sure that the coolant level in the engine is completely full and bled. If still no heat try partially removing the return line from the core to bleed coolant through. (the inlet is the one from the head.) Be careful removing the lines from the core as it's easy to break the core pipes. It sounds like the heater core is air locked.

SIXSLUG

Ha ha! Old joke around here...

I parked my truck pointing downhill on a pretty good slope and let it idle for a long while. I think this helped burp the heater core as I had read about the difficulty of getting an airlock out of it before I flushed and cleaned the radiator back when I bought it and removed/relocated the puke bottle.


The innards of my cooling system were spotless, I'm not sure where all teh sediment and stuff is coming from on others trucks...

duster75

Thanks busboy how do I know block is bled? Have pulled bleed screw several times on head and no air just green. If I "milk" heater hoses heat will get better. Both pipes on core are hot. But little heat in cab. Parked on hill again with no major results

duster75

Sixslug I comprendo my bad. I've tried uphill,downhill (my luck lately) can't get it back to where it was. Starting to wonder if some employee building carquest's radiators dropped a turd in mine

SIXSLUG

That's why I go to NAPA! I know where they live!!Ha ha.

I know its cold out, but can you disconnect the heater hoses and run a garden hose through it and see if you have flow through the core?

duster75

Well I ran the her hard today ( still no fan on and fully covered rad.) With minimal results.whenI got home parked her nose down on hill temp 190. And let her idle.I'll be dammed but I got heat like it used too be. Letting her cool off now we'll see if it sticks. Did not make much of a change on overflow bottle level thats got me wondering if its a fluq.

torquefan

You need to try parking it with the nose pointing uphill. The air wants to move to the highest point, so you want the heater core to be lower than the radiator cap. Once the air bubble moves to the top of the radiator it will vent out and you can fill the void with coolant.

Another method that has worked really well for me on many vehicles is to fill the system with coolant, then open a connection slightly at a high point (like a heater hose). Now I attach a pressure tester to the radiator filler neck and pump it slowly until the pressure has pushed coolant into the heater core. Once the core is full, you can put the connection back together, remove the pressure tester, and top up the rad again. Works every time.

SIXSLUG

An idea I had was to cut a dime sized hole in a racquet ball and then stick the needle from my sports ball pump in it. Place it into the radiator fill hole and press down while pumping pump.

You want the upper heater hose off the engine and pump til primed. Hillbilly, but if you need to get going and are tired of messing around.....

torquefan

Sounds like a great idea. Same thing I do with the pressure tester, without having to buy a pressure tester.

duster75

Well finally had a nice day.Tore it down flushed heater core with air and hot water,(fill core and hose up and push out with 20psi air both ways) minimal junk in core.Pulled thermostat filled block and rad. threw thermostat opening.Filled core and hoses as full as I could get them with funnel. Buttoned everything up and..... HAVE HEAT. Doesn't seem as good as before but it was -4 yesterdays high and truck never got to 190 on gauge.Hopefully this problem is behind me.