Water in oil, what to replace

[BoringLumina]

OK, last week I added 1 gallon antifreeze over the 7 day period. Kept checking the oil and only noticed it looked a little higher. Today noticed it was mocha cappucino frothy in the oil fill hole. Took the upper plenum and started removing the intake manifold.

THE INTAKE MANIFOLD BOLTS WERE FINGER TIGHT ON BOTH ENDS I am hoping this is the source of the water in oil. What will I need to replace?? Any suggestions ??

[Juglenaut]

Could very well be that loose intake manifold.

[BoringLumina]

What are you saying, that the manifold might need to be replaced? Why, do they crack? I just figgured after 191,000 miles that the manifold had heated up and cooled down so many times that it loosened up or some thing. The intake has been leaking oil at the thermostat and accessorie ends since I bought the car a year ago. (Guess I should have paid more attention )

Also wondering if I damaged the head gaskets durring the course of running low on coolant. What alerted me to the low coolant was that the heater was going hot/cold/hot/cold and the dash gauge was bouncing. The dash gauge never went into the red, are my head gaskets safe? How do I check without taking heads off? Sounds like headgaskets are a big job, how bad???

[robby1870]

I'd say your head gaskets are fine, since your temp never got into the red. And, I would also say that the oil leak was probably caused by those loose bolts

[SappySE107]

Yeah, change the oil and filter, get new gaskets (if you have a 3100, get the updated lower intake gaskets), and tighten them all up. You would notice if the lower intake is cracked, and its not a common thing to happen. Id run it for a while, check the fluids, and then change the oil again for good measure.

[BoringLumina]

SUHWEEEEEET !!

Where does the dash temperature read from? I know my neighbors 1996 vette had two temp circuts, one was water near the thermostat and one was like block temp or something. One read out on the computer screen and one was the dash needle and he was fretting because he had issues of overheating and the gauges would be off my 20°F at times.

So, do our cars have something like that, two reading points? I just would like to make sure that the gauge not going into the red REALY means I am safe. I just don't want to go through all this and go back to do the head gaskets right away. Where is our temp sensor located?

[RednBlack]

Could very well be that loose intake manifold.

Agree. I would personally check for flatness. Aluminum is my friend, and it sux when taken apart hot. Or being loose. Warpage is a major issue.

[geoffinbc]

This is extremly common. Just do the old re and re with the revised gaskets and torque specs. Use loctite during re assembly. Thats it. This problem is so common on 3100's and 3400's its not even funny.

The aluminum will not be warped if it did not over heat.

[RednBlack]

The aluminum will not be warped if it did not over heat.

I beg to differ..Bolts loose,..Car has been run? Especially the bolts on the end. Already leaking? Check flatness. I deal with Aluminium for a living.

[BoringLumina]

O-Tay,

I think that the end bolts on the manifold have been loose for a long time - like a year plus and 10,000 miles or so. I just never saw coolant loss till I took the car out of storage and started driving it a few weeks before Thanksgiving. There was always a persisent oil leak on the accessory drive side of the engine, I could never find the leak, I figured it was valve cover gaskets or something.

How the heck am I going to check for flatness? I have a T-Square and I don't even know how to use it except to lay it accross the ports. Anyadvice here would help. I just went to the dealership and they sold me intake manifold gaskets and upper to lower plenum gaskets. Along with Locktite and a torque wrench am I good to go or is there something else I ought to do while I'm in there?

[geoffinbc]

Ok well to check for flatness use a straight edge across the ports and see if you can get a feeler guage under the straight edge.

[RednBlack]

I'll give .020" flex. Giving gasket thickness. Anything over needs surfaced.

[robby1870]

To answer an earlier question, the temp gauge reads from the rear head

[BoringLumina]

Final notes, all back together and everything looks OK

OK, car's nack together and to sumarize: The intake end bolts had worked themselves loose. I locktighted all bolts on the reinstall. I will paste what I responded to somebody else:

I have been meaning to go back and thank everybody. The job is long (For me an honest 16 hours total labor) but I was doing anal stuff like cleaning the inside of the intake manifold. That being said the job is just a lot of very basic operations. Here is what I used: 1 new tube red locktite, 1 tube high temp black Permetex, intake gaskets from Autozone ($2 vs $10 at dealership), valve cover gaskets from Autozone ~ $ 12, and intake gaskets from GM $35, 3 or 4 cans carb cleaner, 1 gallon antifreeze, 12 quarts oil, 2 crappy filters and 1 good one. Be careful taking sensors off I broke one of the plastic tabs. So, here is how it goes, take everything off the top of the motor, the more you take off the less time it actually will take. You will have to get that damn hot water tube off from in front of the front valve cover, you will never get the valve cover back on without remiving it. This is the only part that got a little jacked on this job, I had to hit it with a hammer and keep putting screwdrivers under the lip to remove it from the pump housing, I was worried it was going to break but it only bent. The O-ring that comes with the valve cover gaskets is for the heater tube. You will need a torque wrench for the intake manifold bolts, rocker arm studs and valve cover gaskets. Remove everything from the motor especially the altenator and power steering pump(Don't disconnect lines) you will also have to disconnect the fuel and fuel return line (Special tool ~ $ 9 at autozone) . You will have to pull all the rocker arms & push rods. Make sure to keep each set together, I used one ziplock bag per valve and just put a piece of paper with rear/drivers/intake etc. to keep them straight. I cleaned them prior to reassembly, make sure you have a good oil passage through the push rod. I sprayed all the sand, slime and grime down into the oil pan from the lifter valley (Would have been better to clean with compressed air or carb cleaner prior to dissasembly) After all work is done do not start car, drain oil and put new oil and cheap filter in. Then heat up car, add coolant etc. I let mine run ~1/2 hour. Then drained oil, changed filter and I have been running on the second oil fill for 2 weeks. Will change ASAP but I have been checking almost every day for oil color, and changes in coolant level and color, so far so good. I would recomend a Haynes manual. It may sound bad but for $100 and 16 hours I am glad to have may car back. Good luck.