Do you have to use the bleeder when refilling a Dodge 4.7 ?

I drained and replaced the antifreeze on my farm pickup - a 2002 Dodge 1500 with a 4.7 this last weekend. I see there is a bleeder plug on top of the engine to release trapped air, but didn't know if it actually had to be used. I am familiar with bleeding the air on a Ford 3.8, but this 4.7 looks like it should bleed itself via the upper radiator hose. It did get hot after I added new antifreeze/water. I did check the thermostat in a pan of boiling water and it opens well. Took 15 miles to top out the temp gauge yesterday when the engine was cold and just started, but driving. I would let it cool down 10 - 15 minute, check the antifreeze level after I got the pressure off and go again. Seems like it only took 5 miles to overheat again after the engine was hot. Did that a couple times before I got home. Sure thought is was the thermostat but as I said it opens well in a pan of boiling water. Seems like it really didn't loose that much coolant each time if any. I don't run it while overheated as I know the 4.7 engine will start to pop out the valve seat inserts if they get hot - that is what an expert engine rebuilder told me. Any ideas????? Do you really have to release any air with the bleeder? Thanks

Can't hurt anything to try it.
Walt

Whay do you think they put it there if not needed they would have saved the money. dud

I"m GUESSING they didn"t put it there just for the fun of it! I don"t know anything about your Dodge, but some years ago owned a Grand Prix and you HAD to use the bleeder every time you replaced the coolant so it wouldn"t surprise me if your Dodge was the same way.

If you haven't figured it out by now---

If there is no coolant in the engine and you try to fill it with the thermostat in place (closed when cold), you'll have only locked air in the block and no warm water to open the thermostat. Don't take long to ruin an engine that way.

Anytime a replace a thermostat, I drill a couple of small (1/8") holes in it to bypass the thermostat.
This has made it much easier to fill the cooling system and reduce the possibility of air locks.

Rich

Crack the bleeder open while its running. Close the bleeder once you have a steady stream of coolant coming out the bleeder.
Spitting from the bleeder is an indication there is air still trapped.

RCP,

I do, too.

D.

Yes.

Yes, use that plug to bleed the system. The thermostat is in the bottom hose on that engine so that pipe plug will get almost all the air out the top. I have a pipe nipple and hose arrangement to a bottle that I use to do this, to avoid getting anti-freeze on the belt, which will make it squeek terribly for a long time. After bleeding, fill and run it for 10 minutes , shut off for 10 minutes, top off, repeat 2 or 3 times. All done. PS - that pipe plug can be in there VERY tight and can round out sometimes, I heat it slightly with a propane torch to soften the pipe sealer.

Was it overheating before ?

If so try leaving the thermostat out. Look for air bubbles from a blown head gasket.

Local guy who parts out Dodges says stay away from any with an engine that ends in .7 they don't last like the ones before that ended in .9