View Full Version : Chocolate Milk in the oilpan

10-07-09, 06:06 PM
Hi all...Im new to the board and have been reading many posts pertaining to the Norstar 4.6 head gasket problems. Well, after all the reading Ive done on here I have decided to take on the project on my 99 deville 4.6 VIN Y. I have a lift in my shop so getting the engine out the bottom wasnt bad.
A little background. I bought the car from a guy who told me that the car was overheating...I checked the oil and saw that there was water in it..hence it looked like chocolate milk. I figured that it was the head gaskets as mentioned on here. I removed the motor and began disassembly of it and got to the point of removing the heads. The part that bothers me is that all 20 bolts made that loud snapping sound as so many mention on here. Furthermore none came out with the threads on the bolts. Some bolts appeared to have oil or gravel on them...but not sure if that was from the bolt hole or from pulling the bolt out. My question is has anyone ever seen this scenario of water in the oil and no apparent bad holes and still had it be the head gaskets? Im worried now that there may be a crack someplace.As far as the gaskets themselves look, there are no real traditional descernable blown spots. Any help is appreciated!

10-07-09, 07:13 PM
If your engine has an oil cooler (2 lines running from the oil filter adapter to the front of the radiator, passenger side tank) then those have been known to rupture, putting coolant into the oil. I say engine oil cooler because transmission fluid (cooler rupture driver's side tank) turns the coolant pink.

Pressure test the oil cooler, if there is one - if not, you're in the cracked block arena.

In any event, you now have to insert the block to get the new bolts (yes, new head bolts) to hold.

Wish you had come here before you dropped the engine........20/20 hindsight. But you still have a nice car............

10-07-09, 07:18 PM
There is no oil cooler on the car. If the block is cracked, is it in the head bolt holes? Will timeserts correct this problem?

10-07-09, 07:24 PM
Not likely.

10-07-09, 07:32 PM

10-07-09, 07:42 PM
are we thinking the block is junk? is water in the oil not a common symptom of the head gaskets?

10-07-09, 07:47 PM
The Northstar rarely puts coolant in the oil when a HG goes. I'm with Sub, oil cooler or block.

10-07-09, 07:55 PM
Ouch is right! What are my options? Like I said there is no oil cooler. So if is one of the two it leaves the block. Is there a fix? or is the block junk? Is a cracked block a common problem?

10-07-09, 08:08 PM
Yeah, if the block is cracked, it is junk. I suppose you could find someone who is good at welding aluminum and see if it can be repaired. No, it is not common at all. In fact, from what I've seen here, I'd call it rare.

10-07-09, 09:31 PM
I think we have read of some people that had obvious external cracked blocks. Pretty sure Jake has also mentioned some cracked blocks.

You could definitely have had a leaking HG with 20 good bolt holes, and my gaskets did not show a coolant leak..not exactly. What I saw was some erosion with no distinct seal line between adjacent cylinders, in the fire ring area...I don't know, maybe that's the traditional blown spot you are referring to?

10-07-09, 09:38 PM
I did the headgaskets on my dads 99 eldorado. None of the bolt holes were stripped, yet there was coolant in the oil. 2 of the cylinders were filled with coolant as well though. The oil looked like mustard from the dex-cool.

10-07-09, 10:54 PM
when i pulled my motor i had excessive chocolate milk in the oil pan, but when i pulled the rear head the gasket behind #7 had a 1/4 inch spot corroded away. I replaced my gaskets and used jake's studs. The only issue i have now is the jug on the radiator is dripping now. Most of my bolts came out clean, but when i blew air in the holes aluminum came out at me. Thus the stud kit. the studs are by far a superior design to the factory bolts. Not sure why GM thought it was a good idea to use such a fine threaded bolt for the heads. Just didn't leave a lot of room for any deterioration. Things that make you go hmmmm. I would pull the motor out and break it down. Take it to a machine shop and have them check the block for cracks. Then upon finding a crack just buy one from Jake with studs already in it. new bearings, rings, some gaskets, a little blood, a few knuckles, and your good to go again ;) Good luck.

10-08-09, 12:51 AM
The fact that some of the bolts had "oil or gravel" on them means the HG's were leaking. I'm sure all the N* head bolts are in blind holes.

The N* was designed so coolant contaminating the oil through the Head Gaskets is minimized. The HG failure has to be pretty catastrophic to allow coolant to travel that far. The fact you see no obvious HG failure tends to leave a cracked block.

Are you sure you don't have an oil cooler? No engine oil lines going to the radiator?

10-09-09, 07:59 PM
Update...I brought the heads to the machine shop to be magnafluxed yesterday along with the head gaskets to show them. The guy at the machine shop says both head gaskets were blown between the front cylinder and water jacket. He showed me the black carbon spots between numbers 1 and 2 and the front water jackets. Good news that the gaskets were indeed blown. Im awaiting to hear back about the magnafluxing to check for cracks. I next have to disassemble the short block to have the block mag'd too. He highly reccomended doing rings and bearings because he said lots of late model gm engines are prone to knocks once they run with water in the oil. Can anyone reccomend where tio buy a ring and bearing kit?

10-09-09, 08:38 PM
I have never heard of that on a Northstar. The bottom end (minus the oil pan gasket) is usually very bulletproof. The only occurrences of bearings failing and stuff like that, that I know of, happened because of oil problems.

However, you should stud the block or at least timesert it before putting it back together. The aluminum is already compromised and you probably don't want to do the job again any time soon.

10-09-09, 08:52 PM
Definately no oil cooler. The holes in the oil filter assembly are plugged with hex plugs. I assume thats where the cooler lines would have gone. Now that I know that the head gaskets were both blown Im wondering if the coolant didnt seep into the cylinders and bleed past the rings. The car did sit for over a year the seller told me....keeping my fingers crossed no cracks.....

10-10-09, 10:06 AM
OK - If the car sat for a year with blown gaskets, then that's the chocolate milk explanation, but it also complicates things because the engine is probably totally junk. All those bearings and polished parts cannot stand being wet for a year.........rust and corrosion are certainly present. What did the cams and valve springs look like when you pulled them ???

You're going to need all newcam cover, halfcase and oil pan seals, and a GM/Helm Factory Service Manual. This engine is like no other we're used to working on...............

If the crank journals are pitted/rusted you're sunk because GM says the crank cannot be turned or refinished and there are no stock oversize bearings available, BUT apparently you can get crankshaft kits, bearings, pistons and rings from www.rockauto.com.

10-11-09, 09:24 PM
The top end was clean and rust free. The engine ran before I pulled it. I started it to pull it onto the trailer when I bought it and off into the shop. I plan to do main and rod bearings and rings as well as habve the block mic'd and cleaned. Iv built many engines in my time but never one of these. Are they VERY different o do? I also have a Helm manual on order. Book 1. Claims to be the one of two with the engine stuff in it...Any special tools necessary?

10-12-09, 05:58 AM
Sub - oversize bearings are available. Clevite makes them.

10-12-09, 11:02 AM
Yeah - 2 avenues of info on that. The GM manuals say NO and the aftermarket rebuilders say YES.

..............so if there are cranks and oversize bearings on the street, then someone is set up to regrind/polish the crank journal radius fillets. RockAuto has several bearing options as well as pistons/rings.

Clevite 77 is the only bearing set I use in the Olds engines.

10-13-09, 10:18 AM
OK...verdict is in from the machine shop....Cracked block, one cracked head and both exhaust cams bad.....basically a pile of junk!!!

10-13-09, 11:04 AM
:eek: Yup, good boat anchor.

10-14-09, 03:19 AM

10-20-09, 07:37 PM
OK...picked up another engine from the junkyard. Its out of a 97 Deville. It has 108K on it. Guaranteed running and warantee is for 6 months. However, I plan to replace head gaskets and timesert it before I put it in....Any objections or ideas why I shouldnt????

10-20-09, 08:13 PM
The motor has the same VIN code right?

Also have you cosidered studs over timeserts? I think everone here is in favor of the stud...

10-20-09, 08:26 PM
Yeah, that ^^ , or look at Norm's Inserts - a bit beefier than Timeserts.

10-20-09, 08:54 PM
yes VIN is Y on both blocks. Id be interested in finding out about the studs..is there a website? and are there instructions provided about doing the install with the studs?

10-20-09, 09:06 PM
www.northstarperfomance.com is the official website but we are lucky enough to have the man behind the studs right here on CF 97eldocoupe is his screen name and I do believe he has posted in this thread..

Im sure if you PM him he will give you any answers you need..