: damm am i hard headed...over heating still

04-27-09, 11:24 AM
yeah its me again...my deville still seems to run hot...and i have done all the forum checks etc.and big thank you for those who answered my first posting.well im gonna do the exhaust in coolant test in a couple of days waiting for new coolant to settle to get a accurate reading.but i noticed that i drive around with heater off for on the average of 25 minutes and it goes one notch above half turn on heater and it goes to normal and has never spit out coolant or air bubbles from coolant jar and i can pretty much drive any where with heat on..when this problem started or at least when i noticed the problem i was on my way to run an arrand and drove like 80 miles there and back with heat on and made it.i have always felt like there is a circulation problem and i have done pintle check cleaning flushing etc,could heater core have a clog.this car was involed in a accident and coolant jar broke a bit at bottom which hose goes out to the system but like i said its not leaking i had to make a hose invention to use the container may be coolant jar has somthing to do with it,its filled and does not ask me for coolant and if i take my invention of hose that i put antifreeze comes out of it. also noticed to refill system after flush the coolant jar only took like half bottle to fill and had it on for a long while and none of it never made it to radiator i had to take off upper hose and put a bottle thru there well theres my long story ...im loseing hope and gaining momentum in a for sale sign or takeing it to auto auction but it such a pretty car pearl white...and im a sucker for caddys but im all out of ideas..hope any body can shed some light on this subject thank you guys .....at least i vented lol....thanks again thank you...

04-27-09, 12:18 PM
If you have jury rigged the surge tank and it is not connected as designed with the proper pressure cap in place, is not filled halfway up with 50/50 coolant, COLD, then the system cannot pressurize itself. That leads to several problems, including air pockets in the cooling system, cavitation of the water pump, improper coolant level, and, if the system is not pressurized, then the coolant boils at 216 degrees instead of around 250.

Troubleshooting a jury-rigged cooling system, particularly on a Northstar, is an exercise in futility.

04-28-09, 05:35 PM
I am not following this at all. :bonkers: IF as Sub said, you bypassed the surge tank you redesigned the system and all bets are off and you are on your own.

04-29-09, 02:58 PM
hi guys what i meant to say is that this car was in a accident and coolant jar broke...just were the thicker hose goes out to the system.jar is not cracked but maybe from impact its not letting it purge system like it should.i orderd new coolant jar from dealer it just came in today.and yesterday i replaced radiator cap.it seems that so far with radiator cap it stopped overheating i drove on it yesterday about 50 miles with heat off and no overheating.im checking on it every so often after i drive to see where co0lant level is.but i knda still feel upper hose with little circulation but maybe thats how it is...im gonna find out as soon as i put new coolant jar in...i will keep u guys informed...thank you guys for your input...

04-29-09, 03:14 PM
Just to keep the terminology consistent, the "coolant jar" you speak of is called the surge tank.

04-29-09, 10:36 PM
hi guys i think problem is solved....it was the radiator cap and not the surge tank...i noticed yesterday that after i changed it i could drive and not have the heater on.i put a new surge tank any ways cause i really dont want to catch northstar head gasket syndrome.although i think im in trama but i love them thanks for your input and know how...great caddy forum.

04-30-09, 01:31 PM
Another satisfied customer