Bleeding air from Heater Matrix
I have done a full empty of the cooling system, not by choice, hose blew off the thermostat housing.
Replaced hoses, stat etc got the air out according to RAVE. Problem Is I can hear WATER in the heater core so I must have air in there how can I get it out?
Before hose was running at 216, changed out all but Radiator and water pump, now with A/C on 206. Other 4.0 runs at 194 and the two 4.6 run at 194 so I am GUESSING air in the system.
Replaced hoses, stat etc got the air out according to RAVE. Problem Is I can hear WATER in the heater core so I must have air in there how can I get it out?
Before hose was running at 216, changed out all but Radiator and water pump, now with A/C on 206. Other 4.0 runs at 194 and the two 4.6 run at 194 so I am GUESSING air in the system.
bleed the system cold, elevate the recovery tank, pull the plug from the hose and fill the recovery tank until all the air come out of the bleeder screw, takes a bit of time don't close it right away
Tried that but MUST HAVE BEEN to fast looking for results!
The only other option I use is to pressure bleed but you need the pressure bleeding kit. I modified my brake pressure bleed kit to fit a quick release rad test cap and by pressure bleeding it never fails.
Even when you bleed the system properly, there will be some air left behind in heater core,, it will take few cycles of engine warming up & cooling down completely to get rid of all the air in heater,,,
If you want to expedite the cycles, raise front tires by at least a foot, that puts the heater core lower than front of the engine, (any way that is easier, drive on a ramp, or curb, or put something sturdy under tires). Then bleed system with cold engine to get rid of most air, then replace expansion tank cap, turn engine on & let it get to full temp while front is still raised, now turn off engine & let it completely cool off,
This will get red of most of air but not %100, then you can drive around safely, after a few more cycles of heating up & cooling down in next few days you will notice a little more drop in coolant level, it's the sign that all air is out now, just refill tank, & you will be good,
Because of the stupid design of heater core location , it always takes more than a few cycles of heating up & cooling down to get rid of all the air in heater,
If you want to expedite the cycles, raise front tires by at least a foot, that puts the heater core lower than front of the engine, (any way that is easier, drive on a ramp, or curb, or put something sturdy under tires). Then bleed system with cold engine to get rid of most air, then replace expansion tank cap, turn engine on & let it get to full temp while front is still raised, now turn off engine & let it completely cool off,
This will get red of most of air but not %100, then you can drive around safely, after a few more cycles of heating up & cooling down in next few days you will notice a little more drop in coolant level, it's the sign that all air is out now, just refill tank, & you will be good,
Because of the stupid design of heater core location , it always takes more than a few cycles of heating up & cooling down to get rid of all the air in heater,
Ditto on raising the front of the truck up a foot. LR has it as SOP for both the RR and D2 when installing a block heater (electric coil which warms engine for winter starts - replaces soft plugs on side of block.)
I burped the system per the factory (RAV) Each belch of air translated to 3 deg LOWER temp.
Per the UG
Round one, no burp yet = 212 High reading
Round two (one burp) = 209 deg High reading
Round Three (one burp) = 206 deg High reading
Round four (one burp) = 203 deg High reading
I just got back from a 10 mile run and was sitting at 204 NO A/C ambient at 78 deg.
FLIR shows 199 deg at the HEATER hoses and 174 deg at the TOP hose at the Tstat.
Will burp in am see what happens. HAVE NOT elevated the front YET seeing how far this will take it. Target is 194 deg at 60 mph on flat road. which is what the P-38, D1 and LR3 show on their UG.
Would love to post the FLIR pictures but HOW??
Per the UG
Round one, no burp yet = 212 High reading
Round two (one burp) = 209 deg High reading
Round Three (one burp) = 206 deg High reading
Round four (one burp) = 203 deg High reading
I just got back from a 10 mile run and was sitting at 204 NO A/C ambient at 78 deg.
FLIR shows 199 deg at the HEATER hoses and 174 deg at the TOP hose at the Tstat.
Will burp in am see what happens. HAVE NOT elevated the front YET seeing how far this will take it. Target is 194 deg at 60 mph on flat road. which is what the P-38, D1 and LR3 show on their UG.
Would love to post the FLIR pictures but HOW??
Below the submit reply button, there is an 'Additional Option' section which has a button to 'Manage Attachments', you can upload photos that way. Or just link to them if you host them somewhere else (Flickr, Imgur, Picasa, etc).
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