"Burping technique" Clarification

[TortolaTim]

"As for the air block, it's called "BURPING" and all you need to do is take the 3/8 inch hose off the bottom of the thermostat.  Pour distilled water or antifreeze or the 50/50 mix into that hose with a funnel until water comes out of the bottom of the thermostat.  Loosen the hose clamp and pull the hose off.  Hold that hose up above the thermostat and pour the stuff into it until the water comes out of the bottom of the thermostat - the nipple that you just removed the hose from.  Once that happens, just put the hose back on the nipple under the thermostat housing and tighten up the hose clamp.  Put some Lanocote on the nipple to make it easier to remove the hose the next time. That gets the air out of the loop of hose that goes to the hot water heater and avoids overheating at startup and does not require that you rev the engine while the thermostat petcock is open.  You won't need to open the thermostat petcock at all."

I'm planning on replacing some hoses before haulout, and decided to change the coolant out as well. I just want to make sure I have a complete grasp of this burping technique. First drain/flush/replace coolant from manifold radiator cap, THEN burp the air out.....
Dumb question, but this entire burping process is done with the engine RUNNING?, and the additional AF you add will circulate through the system and then come out the bottom of the thermostat, correct? Once there is uninterrupted flow from there, the air should be  evacuated and then you can re-attach the hose?

[KWKloeber]

Tim

That "filling" is done with the engine off, you're simply adding coolant to the WH hose loop => to the top of the pump => to the engine block -- until coolant fills up to the bottom of the TStat housing.

"Burping" is actually with the engine running (mentioned in the old post) where you do "burp" out air that is left in the system by revving the engine to force it thru the system and and letting it escape out of the thermostat petcock.   On the 30 we have another method (same engine, different WH location) -- remove the coolant pressure cap (on a COLD engine,) rev the engine (which draws down the coolant level) and add coolant until it's topped off.  That forces air to and out of the pressure cap neck, which you replace with coolant.  But if you fill thru the WH loop you shouldn't need to do the other(s) -- they're just additional options in case you still have air in the system.

ken

[Stu Jackson]

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First drain/flush/replace coolant from manifold radiator cap, THEN burp the air out.....
Dumb question, but this entire burping process is done with the engine RUNNING?, and the additional AF you add will circulate through the system and then come out the bottom of the thermostat, correct? Once there is uninterrupted flow from there, the air should be  evacuated and then you can re-attach the hose?

Engine off.  Fill the WH loop, close up hose.  Then start engine.  Yes, the entire purpose of this method is to eliminate all the air in the system.