02 DTS cold air

dtino said:

OK. Here goes. I have a new water pump that is working great, with help I got to see that it is working. I took the car down and had it flushed out, drove the car for 5 days and worked great. On the evening of the 5th day I stopped to get a wash and the car started to heat up a little bit and the heater blew "cold" air! The car never heated up before. I thought ok the cleaning may have messed up the thermostat, so I put a new one in and still cold air. all hoses hot but the one at the core. I seen that the overflow was not moving, I when and put a new one on. I have heat and the back hoses are now getting warm. BUT, the heat is not hot like it was, I paid to have the total system flushed, that included the core. How to do I get all the air out of the system? If the system is clean then this can be the only problem left, other than replacing the core. Has anyone done this before and knows how to get the air out?
Many Thanks

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I thought ok the cleaning may have messed up the thermostat,
so I put a new one in
I hope you used either an ACDelco or STANT brand T-stat -
and not some el-cheapo house-brand unit -

How to do I get all the air out of the system?
the system is SUPPOSED to be self-purging -
through the PURGE LINE -

the PURGE LINE is the only way of expelling air from the Northstar cooling system -

it is a 3/8 diameter hose that goes from a hollow bolt in the thermostat/waterpump housing area of the engine - and plugs onto a nipple on the side of the SERGE TANK -

with the engine running - there should be a gentle - constant flow of coolant - from the engine - to the serge tank -

if there is no flow - the most likely cause is a blockage in the hollow bolt -

follow the hose towards the engine - with the engine OFF - remove the hose - use a straightened metal coat hanger - or something similar - and poke it into the hollow bolt -

the coat hanger should go in about 2 1/2 inches -

once the hollow bolt is cleared - you can briefly start the engine to verify coolant flow - be sure to use some sort of container to catch the coolant so you don't make a mess -

check the hose and serge tank for blockage -