Oil test shows coolant contamination in 4.9!
Cadillac
 

Cadillac Forums | Help Us Help You | Advertise | Cadillac Parts | Cadillac News | Cadillac Classifieds / (Old System)

Cadillac Technical Archive | Cadillac Dealers | Cadillac Reviews | Cadillac Dealer Reviews | Cadillac Vendors

CadillacForums.com is the premier Cadillac Forum on the internet. Registered Users do not see the above ads.
+ Reply to Thread
Results 1 to 6 of 6
HT4100 4.1, 4.5, 4.9 Discussion, Oil test shows coolant contamination in 4.9! in Cadillac Engine Technical Discussion; I had the oil in my '94 Deville tested by Blackstone Labs, and they said the following: "The oil sample ...
  1. #1
    caddydaddy's Avatar
    caddydaddy is offline Cadillac Owners Connoisseur
    Automobile(s): 2005 Escalade 6.0L 2WD, 2007 Jeep Grand Cherokee Limited CRD
    Join Date
    Jan 2003
    Location
    Gales Ferry, CT
    Age
    32
    Posts
    3,668

    Exclamation Oil test shows coolant contamination in 4.9!

    I had the oil in my '94 Deville tested by Blackstone Labs, and they said the following:

    "The oil sample from your Cadillac tested positive for coolant contamination. Potassium, silicon, and sodium are the hallmarks of the anti-freeze. We had expected to find wear higher but that wasn't the case. Universal averages for the 4.9L are based on an oil run of ~3,200 miles. If you keep your oil runs around the 4,000 mile mark you should be able to live with this problem for a while. If you have noticed any loss of anti-freeze then you can be sure a problem exists. Insolubles were low, showing good oil filtration. Check back to keep an eye on your engine."

    Since intake manifold gasket leaks are common on these engines, is that the first place I should look? I have noticed a slight coolant loss, but other than that, nothing unusual. No overheating or rough running. The engine has 140,100 miles and it was 4,069 miles before the oil was changed with Rotella 15w-40.

  2. Remove Advertisements
    CadillacForums.com
    Advertisements
     

  3. #2
    noahsdad's Avatar
    noahsdad is offline Cadillac Owners Connoisseur
    Automobile(s): '87 SDV
    Join Date
    Jun 2005
    Location
    Michigan
    Age
    55
    Posts
    1,296

    Re: Oil test shows coolant contamination in 4.9!

    Intake gaskets rarely result in coolant contaminating the oil. Hate to be the bearer of bad news, but you might be looking at head gaskets here. Get a cylinder pressure test done to diagnose.

    Do you keep up with the cooling system maintenance and use the sealant pellets? They won't help if the gasket is already gone, but Blackstone's assessment indicates the contamination isn't significant enough to cause damage yet, so it may just be a weak spot that the sealer could shore up.

  4. #3
    caddydaddy's Avatar
    caddydaddy is offline Cadillac Owners Connoisseur
    Automobile(s): 2005 Escalade 6.0L 2WD, 2007 Jeep Grand Cherokee Limited CRD
    Join Date
    Jan 2003
    Location
    Gales Ferry, CT
    Age
    32
    Posts
    3,668

    Re: Oil test shows coolant contamination in 4.9!

    Yes, I do keep up with cooling system maintenance. And the previous owner did to, I could tell he used the supplements tablets. It had 94k when I bought it, and I've changed the coolant twice in the 50k miles I've owned it, and used the supplement tablets.
    Is it possible for it to leak between the timing chain cover and get in that way? When I first bought the car, there was a coolant leak in that area, and it was some loose bolts. I'm not sure if a bad gasket there could cause coolant to leak into the engine.
    Yeah, I'd really hate it to be a head gasket, it's a very nice Deville for it's age, and runs great! I'm really bummed out about this!

  5. #4
    caddydaddy's Avatar
    caddydaddy is offline Cadillac Owners Connoisseur
    Automobile(s): 2005 Escalade 6.0L 2WD, 2007 Jeep Grand Cherokee Limited CRD
    Join Date
    Jan 2003
    Location
    Gales Ferry, CT
    Age
    32
    Posts
    3,668

    Re: Oil test shows coolant contamination in 4.9!

    OK, an update: I tested the cooling system for hydrocarbons using a block tester http://www.rxauto.com/blocktest.htm . I did this test three times, and the fluid did not change color. So either the head gasket leak is really small, or the leak is not from the heads. My only other guess would be a leaking intake manifold gasket, where it is leaking into the lifter valley and down into the engine oil.

    Any thoughts?

  6. #5
    HUF's Avatar
    HUF
    HUF is offline Cadillac Owners Connoisseur
    Automobile(s): 1995 FWB 100,*** miles CURRENT. 1991 Seville 175,000 SOLD
    Join Date
    Dec 2005
    Location
    MA
    Age
    55
    Posts
    1,994

    Re: Oil test shows coolant contamination in 4.9!

    It could be oil cooler connections inside of the radiator. Head gaskets on 4.9s are good. Do not worry much, just drive it and check the coolant level frequently.

  7. #6
    caddydaddy's Avatar
    caddydaddy is offline Cadillac Owners Connoisseur
    Automobile(s): 2005 Escalade 6.0L 2WD, 2007 Jeep Grand Cherokee Limited CRD
    Join Date
    Jan 2003
    Location
    Gales Ferry, CT
    Age
    32
    Posts
    3,668

    Re: Oil test shows coolant contamination in 4.9!

    It has a new radiator, so it's something in the engine. I'm not too worried about it now, but leaks don't get better or lessen as time goes by! I'd really like to keep this car another 2 or 3 years, so I'd like to find out exactly what's going on with it now.

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.
If you do not want to register, fill this field only and the name will be used as user name for your post.

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

Please enter a valid email address for yourself.

Log-in

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.



Bookmarks

Cadillac Posting Rules

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
Read about Lincoln | Buick | Kia Forte Forum
Need products for your Cadillac? Check out your options at the links below:

custom floor mats | Cadillac Chrome and Black Chrome Wheels | window tinting