Mechanics

OIL IN COOLANT EXPANSION TANK

Ford Aspire

I have a 1997 Ford Aspire, 5-speed manual transmission, 90,000 miles.

At my last oil change, I observed oil in my coolant expansion tank. No coolant appears in the oil. Since this is the case, I assume that the oil is under pressure where it is leaking into the coolant. Having said this, I suspected the head gasket was cracked where the pressurized oil makes its way to the top of the engine. I pulled the head only to find no obvious head gasket cracks or stress. The head and block, where they meet, looks good too.

I am stuck. Should I replace the head gasket not knowing if I caught a head gasket going bad very early or replace the head and gasket? I guess another consideration is that the block could have a problem around the oil pump?

One final thing to add. Over the winter when the car sat for more than 10 hours, one of the hydraulic tappets in one of the rocker arms sounded like it was sticking. After re-starting the engine several times when thus happened, the tapping would go away. This happened 8-10 times. (Probably not related to the oil in coolant?)

HEEEEELLLLP. Thank you, Doug
Avatar
Doc Doug
July 21, 2007.



Since you took off the head gasket coverings it would be smart to replace it and put some nice sealing compound on it also see if it fixes the problem. I think it is the headgasket that let the oil in with the coolant.

Blackop555
Oct 18, 2007.
Replaced the head gasket and all eight valve tappets. 400 miles later, sounds and looks good. Time will tell.

Doug

Tiny
Doc Doug
Oct 19, 2007.
Now at 98,000 miles, I have found oil in the coolant tank again. I am at a lost. The machine shop pressure tested the head, when it was shaved. I replaced the head gasket and torqued the head bolts properly. That was a lot of work to still have the same problem.

What to do. What to do?

Tiny
Doc Doug
May 11, 2008.
Is it possible its transmission fluid from the radiator transmission cooler?

Tiny
Mastertechtim
May 11, 2008.
>is it possible its transmission fluid from the radiator
transmission cooler?

I should have mentioned in my first post, the vehicle has a manual tranny with no oil or tranny cooler in the radiator.

I did re-use the head bolts... but was told this is fine since they are not stretched to hold torque. Funny thing is, Chilton's says to replace with NEW bolts and other repair guides don't specify.

The oil that I am finding in the expansion tank and filler neck is not a lot.

See the photos of the head and block (before and after.)

How about the oil pump? Is there any way at all that the oil pump could be leaking into the coolant?


http://www.2carpros.com/forum/automotive_pictures/87571_IMG_3810_1.jpg



http://www.2carpros.com/forum/automotive_pictures/87571_IMG_3830_1.jpg



http://www.2carpros.com/forum/automotive_pictures/87571_IMG_4637_1.jpg



http://www.2carpros.com/forum/automotive_pictures/87571_IMG_4638_1.jpg


http://www.2carpros.com/forum/automotive_pictures/87571_IMG_4667_1.jpg


Tiny
Doc Doug
May 11, 2008.
There could be a bit of oil in the system that is still working out, try a whole cooling system flush.

The bolts could be loosening up, try retapping the wholes and redie the bolts and use a spot of locktight on them when reinstalling
also use rtv sealent on the parts of the gasket near the manifold.

Blackop555
May 12, 2008.
I have thought of the existing oil in the coolant system theory.

With respect to using rtv sealant on the parts of the gasket near the manifold. Do you mean intake or exhaust manifold. (I assume the intake, since this is where the oil is pumped up.) I don't believe that rtv should be used on this type of head gasket. This type of gasket is made to move with the AL head and iron block.

I thought of simply tightening each head bolt evenly, persuant to the tightening sequence.

Tiny
Doc Doug
May 12, 2008.
Rtv sealent is only used on the corners of the tabs where the intake manifold sits, helps seal it best, try retorquing the bolts in proper sequence and see how it does, if thats not it

Blackop555
May 12, 2008.
Since this is a straight four, I don't understand how I would use RTV at the corners where the intake sits.

I will try retorquing the head bolts without removing them. (I also considered removing each and replacing with new ones. One by one, to avoid a full loss of seal. I fear that doing this might warp the AL head.)

Tiny
Doc Doug
May 12, 2008.