Coolant in oil!

[jdrh]

I've seen a lot of posts concerning intake gasket replacement, but am not sure of the symptoms that indicate the problem. Can antifreeze get into the oil because of bad intake gaskets? My wife drives a 98 Venture which now has 170,000+ miles on it. For the last year or more, I've had to add coolant to the reservoir every few months, but the oil has always looked ok when I changed it.
That is up until the beginning of this week. On her way to work, the temp gauge went up to hot and there was no heat from the heater. I added almost a gallon of coolant to the reservoir and decided to check the dip stick. Not good! It looked like coffee with cream in it. And it was about a quart over the full mark. I guessing it's a cracked head since there are no bubbles in the coolant. Do you think that is a good guess? The engine continues to run fine.

[Airjer_]

It is entirely possible for the intake gasket to fail and allow coolant into the oil.

[merc81]

If the engine is running fine, no white smoke when starting cold, then your LIM is likly the problem--and it sounds like you better address the issue right away. Water in the oil will cause the engine bearings to wear; these engines are known for popping cam shafts and I think the water in the oil is one good reason.

Don't park the van and fix it later; fix it now or take it to a shop now. That coolant didn't just leak out--it went into the engine which is something you don't want to happen.

[jdrh]

Thanks for the replies. I will proceed with the hope that it is the LIM gaskets.
I was seriously thinking of getting rid of it, but now will pull the intake. There are plenty of posts about this problem, so I should have all the info I need.

[merc81]

Originally Posted by jdrh

Thanks for the replies. I will proceed with the hope that it is the LIM gaskets.
I was seriously thinking of getting rid of it, but now will pull the intake. There are plenty of posts about this problem, so I should have all the info I need.

One thing you may need it this:
Product : Quantity : Price
[1AEIM00014] 1996-2003 GM 3.1L & 3.4L Intake Manifold Gasket Kit With Bolts : 1 : 39.95

Subtotal : 39.95
Shipping : 8.00
TOTAL : 47.95

That's from 1aAuto and is the newer gasket kit. I'm sure it went up in price, but that's the gasket to purchase.
John

[discnik]

Just to be sure it is not the head gasket that is bad you can pressurize the cooling system, remove all spark plugs ,( the 3 in the rear can be a pain with out a lift) crank over engine and see if any water comes out of plug holes. If it is the head be sure to mark which push rod went where. Had one in our shop that a friend of a friend of the customer did the fix and bent several valves.

[roadrunner2]

I don't know what LIM stands for but intake manifold gaskets is IMG.

If you're tearing down the engine to replace the intake gaskets you may be wise to go a bit further and physically inspect the crankshaft journals and bearings for damage.

There won't be any point of replacing the IMG if the bearings are shot.

The fact you had to add so much coolant and have driven so long since seeing the symptoms tells me this.

['97ventureowner]

Originally Posted by roadrunner2

I don't know what LIM stands for but intake manifold gaskets is IMG.

When referring to these engines LIM refers to Lower Intake Manifold, and UIM refers to Upper Intake Manifold.

[roadrunner2]

Originally Posted by '97ventureowner

When referring to these engines LIM refers to Lower Intake Manifold, and UIM refers to Upper Intake Manifold.

Of course, thanks.

[jdrh]

I ended up taking the van to a repair shop. I spent at least a half hour trying to get the pet-cock to turn in order to drain the radiator and finally gave up.
It's turned cold here and I don't have a heated garage, so I decided to let someone else do it. This is rare for me.
The repair shop called me after they had finished changing the gaskets and told me they did a pressure check of the cooling system and that there was a bad leak behind the timing cover. ??? Prior to taking the van in, I had not seen any indication of an external leak. Of course they offered to fix it for another $600. The gasket replacement is costing just under $700.
Any one hear of a coolant leak at the timing cover?

[roadrunner2]

Originally Posted by jdrh

I ended up taking the van to a repair shop. I spent at least a half hour trying to get the pet-cock to turn in order to drain the radiator and finally gave up.
It's turned cold here and I don't have a heated garage, so I decided to let someone else do it. This is rare for me.
The repair shop called me after they had finished changing the gaskets and told me they did a pressure check of the cooling system and that there was a bad leak behind the timing cover. ??? Prior to taking the van in, I had not seen any indication of an external leak. Of course they offered to fix it for another $600. The gasket replacement is costing just under $700.
Any one hear of a coolant leak at the timing cover?

Somebody is either mistaken or is feeding you a line of bull.

There is NO coolant related components within the timing chain cover on your van.

The (external) water pump is above and to the right of the cover and perhaps the water pump is seeping coolant via the weep hole, (if it is, repair the pump) and the fan has blown some coolant onto the cover and that's what they see.

[merc81]

There is NO coolant related components within the timing chain cover on your van.

I'm sorry, but you shouldn't post such a statement when you are not sure or have not seen for yourself what is in there. The water passage surrounds the timing chain on most all chevy engines. While its not common or likely that coolant will enter the timing chain area, it is common and likely that coolant will leak from under that cover.

See this thread also:
http://www.automotiveforums.com/vbul...d.php?t=929295


The front timing chain cover can indeed leak. This would be a hard problem to get at, but it might be done without dropping the engine.
Here is a view of the timing chain showing the gasket that protects water from the pump from getting at the timing chain. The front cover directs the coolant from the pump into each head at the shoulder of the block. The bolts that run through the water passage can and do leak.



I think the shop is treating you fairly. The two jobs are unrelated, but the front cover is easier to do in terms of labor time. The right way to go about it is to drop the engine, but for $600, I don't think they plan to do it that way. Its possible if you just remove the larger bolts and coated them with sealant the leak may stop. You might ask them what they intend to do for the $600--does that price include the installation of a new front cover gasket? If so, its a good deal.

John

[roadrunner2]

Hmmmm, I didn't realise that was there. Thanks for the info John.

[abilyk]

Originally Posted by merc81

I'm sorry, but you shouldn't post such a statement when you are not sure or have not seen for yourself what is in there. The water passage surrounds the timing chain on most all chevy engines. While its not common or likely that coolant will enter the timing chain area, it is common and likely that coolant will leak from under that cover.

See this thread also:
http://www.automotiveforums.com/vbul...d.php?t=929295


The front timing chain cover can indeed leak. This would be a hard problem to get at, but it might be done without dropping the engine.
Here is a view of the timing chain showing the gasket that protects water from the pump from getting at the timing chain. The front cover directs the coolant from the pump into each head at the shoulder of the block. The bolts that run through the water passage can and do leak.



I think the shop is treating you fairly. The two jobs are unrelated, but the front cover is easier to do in terms of labor time. The right way to go about it is to drop the engine, but for $600, I don't think they plan to do it that way. Its possible if you just remove the larger bolts and coated them with sealant the leak may stop. You might ask them what they intend to do for the $600--does that price include the installation of a new front cover gasket? If so, its a good deal.

John

Thank you merc81. That page was exactly what I needed. I just replaced my Timing chain cover gasket because of a bad leak on my 99 transport. Not that bad of a job. did not have to lower the engine or anything. The proceedure also states you should remove the oil pan (a big pain to do) before installing the cover for a proper oil seal to the cover below the crankshaft but I didn't do that either (not neeeded), just use a lot of sealant at the bottom of the timing cover gasket. The other snag I ran into is trying to remove and swing the power steering pump out of the way. There is not enough room to do this when the cover is still bolted on, the fuel rail with the pressure test port is in the way so I just removed the power steering bolts first and left the pump there and then removed the TC cover. I also used a couple dabs of sealant to hold the new gasket in place because mine wanted to flop out from the top while trying to get the cover lined up and put in place (a little tricky with the power steering pump), put the PS pump in place on the cover first then put the cover on bottom first or it will not go on because of the oil pan gasket. Do not need to remove the water pump. I also used thread sealer on the bolts by the water passages. All is good now, no more leaks.