Oil/coolant/exhaust problems

1997 CADILLAC DEVILLE
121,000 MILES • 4.6L • V8 • 2WD • AUTOMATIC
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DBROSDAHL1
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I own the car listed above with a 32 valve Northstar. I noticed it has milky oil and the antifreeze was low. I knew the car leaked oil and antifreeze but it never leaked much. I started noticing it had a funny smell and it smoked when it was running. It steadily got worse and then I noticed it had a misfire. I got the misfire taken care of (it was two wrecked spark plugs) and the smell and smoke went away for about thirty minutes. The next day I had friend come and help get it running (bad battery) and he told me to look at the back so I did it was belching gray smoke then it went to yellow smoke and then black and it was spitting black gunk out the exhaust. It was after that I checked oil and found that it was milky and low on both oil and on antifreeze. I am wondering if anyone knows what could cause these problems and if it is worth fixing? Thank you for any input provided. Sorry for the length of this question.
Dec 2, 2018 at 8:02 PM
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ASEMASTER6371
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Good morning,


From your description, it sounds like you have a failed head gasket. I would have the cylinders pressure tested to see if there is any movement in the cooling system.

https://www.2carpros.com/articles/head-gasket-blown-test

I would not wait too long on this as the longer you wait, the more damage can be done to the main and rod bearings on the crankshaft.

This is a major repair. If you do have bad gaskets you may want to consider replacing the engine with a good used engine. With an engine that old you may open it up and find more issues that can be very expensive.

Roy
Dec 3, 2018 at 4:27 AM
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HARRY P
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It sounds like you may have a blown cylinder head gasket. The head gasket goes between the engine block and the cylinder heads, and seals the cylinders up. A leak here can cause oil to seep into the coolant, or more likely, coolant to seep into the cylinders and engine oil. Coolant seeping in will cause spark plugs to fail, general rough idle, steam to come out of the tail pipe, and sometimes smoke. Here is an article with more information on blown head gaskets, including how to test for it: https://www.2carpros.com/articles/head-gasket-blown-test

I am also attaching an image that is Prodemand's repair cost estimate. This is roughly what you will pay for labor at the dealership for the job. Parts will be an additional few hundred dollars, give or take.

Good luck and please let us know what happens next. We are interested to find out.
Image (Click to enlarge)
Attached Media
Dec 3, 2018 at 4:35 AM
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HARRY P
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I agree with Roy's assessment. It would probably be a better idea to replace the engine. If you go to a smaller shop, it would probably cost less than having the head gaskets done at the dealership.
Dec 3, 2018 at 4:37 AM
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DBROSDAHL1
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Thank you for the responses. I will probably go with repairing this engine due to I do not have the money for a "new" engine.
Dec 3, 2018 at 4:45 AM
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ASEMASTER6371
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Just to add, I would consider a used engine rather than a new engine. The price for replacing the head gaskets may be very close to replacing the used engine.

Roy
Dec 3, 2018 at 5:25 AM
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HARRY P
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Again I am with Roy. Used engine would be the way to go. If you search around, you could probably get one with decent mileage for about $600.00. At least that is what they sell for around here.
Dec 3, 2018 at 1:26 PM
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DBROSDAHL1
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I just found out about steel seal would that be a good way to go? I do not have the money for a new head gasket to get put in or to get an engine. My only other option would be to scrap it and hopefully get a little money.
Dec 5, 2018 at 5:21 AM
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ASEMASTER6371
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No, that stuff never works and produces more issues such as clogs the radiator and the heater core and it does not work. There is no additive for a failed head gasket. The only repair is to replace it.

Roy
Dec 5, 2018 at 6:01 AM
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DBROSDAHL1
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Thank you.
Dec 5, 2018 at 6:13 AM
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ASEMASTER6371
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You are welcome.

We are always glad to help.

Roy
Dec 5, 2018 at 6:14 AM