Nothstar Cooling System Problems

[NXfedRam]

Friend brought me his 97 Cadillac Deville a few weeks ago stating that the radiator was leaking and needed replaced. I confirmed that the end tank was cracked and leaking, and put a new radiator in along with new upper and lower hoses while I was in there. When finishing up and "burping" the air out of the system I noticed that the car seemed to continually burp air out of the system as long as it ran and would do so until the coolant appeared to boil. I let the car cool topped it off with coolant and the car seemed fine.

 

He drove it for a week problem free and then I got a call from him and the car had overheated. I found the problem to be the waterump leaking and the car had simply ran low on coolant. Today I did a waterpump along with a thermostat while I was there, and had the same problem with not being able to get air completely out of the system. The car seemed to drive normal for about 10minutes then the coolant temps climbed to 230-250, car went into limp mode, and coolant puked out of the overflow. It is hard to keeps tabs on coolant temp as the dash display is f***ed up and spiradically reads them.

 

The car passed a block test (no combustion gasses in coolant), and the fans seem to be working fine. I am starting to think Coolant temp sensor as the car does not seem to be as hot as it reads but that wouldnt explain the coolant puking from the overflow?

Any ideas?

[Guest Removed]

been putting the seal tabs in it? caddy recommends putting seal tabs in them any time the coolant system has been emptyed..

 

and just cause it passed the block test, doesnt mean it not having head gasket issue..

 

 

use a temp gun to make sure the temp reading is correct