Northstar drinking coolant - need advice

Cadillac Forums | Help Us Help You | Advertise | Cadillac Parts | Cadillac News | Cadillac Classifieds

Cadillac Technical Archive | Cadillac Dealers | Cadillac Reviews | Cadillac Dealer Reviews | Cadillac Vendors is the premier Cadillac Forum on the internet. Registered Users do not see the above ads.
+ Reply to Thread
Results 1 to 4 of 4
Northstar Engines and System Technical Discussion Discussion, Northstar drinking coolant - need advice in Cadillac Engine Discussion; My 1996 STS with 170,000 miles has taken to drinking coolant. In the last week I drove about 400 freeway ...
  1. #1
    larryntripp is offline Cadillac Owners Member
    Join Date
    Feb 2004
    Boise, Idaho

    Northstar drinking coolant - need advice

    My 1996 STS with 170,000 miles has taken to drinking coolant. In the last week I drove about 400 freeway miles and needed nearly a gallon of coolant to top off the reservoir. This car has always used some coolant but now its going fast. No leaks to be seen anywhere. Can this be anything but a blown headgasket?? Car runs great. Mechanic is testing coolant for exhaust gases. Is this a surefire way to determine a headgasket problem, or should one pressure test the cylinders?

    If it is a blown head gasket, what should I do? Fix the existing engine, find a used engine to replace it, or junk the car and get something else? My mechanic seems pretty spooked about doing the heads on a Northstar.

  2. Remove Advertisements

  3. #2
    etcCanuck's Avatar
    etcCanuck is offline Cadillac Owners Member
    Join Date
    Mar 2004
    Calgary, AB CANADA

    Re: Northstar drinking coolant - need advice

    If your headgasket is blown it will show up in the coolant. You might be losing coolant through the overflow (defective cap) or from over-heating (waterpump). If you do find its the headgasket it is worth replacing, but make sure you time-sert the block while your in there. If you do this than you should be good for a while...

  4. #3
    delzy's Avatar
    delzy is offline Cadillac Owners Fanatic
    Automobile(s): 2000 Dev, 94 FW (crushed), 96 FW Limo (sold), 95 SLS (sold)
    Join Date
    Feb 2005
    The Last, Best Place

    Re: Northstar drinking coolant - need advice

    To test the head gasket, put compressed air in the spark plug hole and see if it comes out the coolant reservoir. There are tons of posts on this subject. I'm not sure of the exact procedure, but it is covered many times in this forum. This is a good one, but will take some time to pore over:

    Good Luck!

  5. #4
    Ranger's Avatar
    Ranger is offline Cadillac Owners Member
    Automobile(s): White Diamond '03 DHS (with DTS floor shift)
    Join Date
    Jun 2004
    Woodstock Ill.

    Re: Northstar drinking coolant - need advice

    Testing for exhaust gasses could be deciving. If the leak is at an intake port, coolant will be sucked out rather than at an exhaust port where exhaust gasses will be introduced into the coolant. If it turns up negative, you might want to do the cylinder pressure test to confirm it. The coolant has to be going somewhere and if there are no leaks then the assumption is that it is being injested.

  6. Remove Advertisements
    Cadillac Forums

+ Reply to Thread
Gear in this thread - Powered by O'Reilly Auto Parts

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.

Please enter a password for your user account. Note that passwords are case-sensitive.

Please enter a valid email address for yourself.

What Cadillac(s) do you own? (Or type NONE)

Please select your insurance company (Optional)

Your date of birth and age are displayed in several places on the forum. Only the administrator will have access to your date of birth should you choose to hide it via the privacy option below.


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.


Cadillac Posting Rules

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts