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View Full Version : Bizzarre issue with a 30v... read this epic saga, can you figure it out?



angry12v
10-12-2011, 06:56 AM
The car is a 2.8 30v AHA
http://i1137.photobucket.com/albums/n506/angry12v/IMG_20110910_212249.jpg


I bought the car with an "overheating" problem. The previous owner had brought it to a shop and they quoted him for a water pump/timing belt job.


I tore the car apart and sure enough, the water pump was toast, and the idler roller had exploded.

I was sure it would have bent valves, so I pulled the heads off and checked the valves. Bank 2 head was fine, Bank 1 head had a few bent valves.

Put all new valves in the Bank 1 head, cleaned everything up, put it all back together with new gaskets everywhere, new headbolts, all torqued properly, etc.

Started it up and idled it for about a half hour while adding coolant and bleeding out the air. It ran perfect.

Decided to take it for a short drive... and it started running hot. Pulled over and shut it off and figured it still had some air bubbles. At this point it started puking oil/coolant mix out of the reservoir. I let it cool down completely, added some water, added some oil, limped it a half mile home.


I figured there was no way the new headgaskets had failed already, so I bought a new oil cooler and installed that. Cleaned out the cooling system the best I could, filled it with water. Added new oil and filter. Idled it for a while. Still a ton of oil going into the cooling system. Drain the oil and sure enough there is some water in the oil, too.


Pulled it completely apart again. Took the heads to a reputable machine shop to have them checked. They were not warped and not cracked. I had them resurfaced just to clean them up of any scratches or gasket marks.

Put it all back together again with all new gaskets/parts, new oil and filter. Started it up. Once again, runs perfect. Added water, idled it until it was up to temp. Lots of oil still in the coolant (I figured from previously, it will take a LONG time to clean it all out).

Shut it off after about 15-20 minutes of idling and drain the coolant/oil mix. Then I go to drain the oil, and only get 2-3 quarts of milky mess out of it, when I had just filled it with 6.5 quarts of fresh oil.



Lost 3+ quarts of oil just idling for a few minutes. Cracked block? Never seen that before...

At this point I'm stumped and so frustrated with it I "can't see the forest for the trees". [facepalm]

If you took the time to read this whole thing, thank you. I'd really appreciate any input.

FNK
10-12-2011, 10:04 AM
You could have added some fluid reactive to UV in the working engine so it would circulate.
Then tearing it apart and using an UV light to spot the leak/crack.

moparfan90
10-12-2011, 12:02 PM
same thing happened to my 1.8t 2 years ago. it turned out to be the oil cooler. its thin metal and somehow it broke allowing fluid to exchange. not sure if your engine has one but if it does. give it a shot.

angry12v
10-12-2011, 12:09 PM
same thing happened to my 1.8t 2 years ago. it turned out to be the oil cooler. its thin metal and somehow it broke allowing fluid to exchange. not sure if your engine has one but if it does. give it a shot.


I figured there was no way the new headgaskets had failed already, so I bought a new oil cooler and installed that.

I've already replaced the oil cooler [:|]

Scotty@Advanced
10-12-2011, 12:13 PM
I've already replaced the oil cooler [:|]

Did you replace the cooler with a new one? Aside from a cracked block or blown head gasket this is the only components that when fails can allow oil/water to mix.

angry12v
10-12-2011, 12:19 PM
Did you replace the cooler with a new one? Aside from a cracked block or blown head gasket this is the only components that when fails can allow oil/water to mix.

Yes, a brand new "BEHR" unit. That was my thought too, there isn't anywhere else (in a non-turbo car) where oil and coolant could mix other than those 3 ways. I have no reason to believe the headgaskets didn't seal properly... so that only leaves one option. But I've never heard of one of these blocks cracking...

walky_talky20
10-12-2011, 12:21 PM
Any possibility of coolant/oil left in the head bolt holes? Tighten them down like that = possible cracked block.

angry12v
10-12-2011, 01:00 PM
Any possibility of coolant/oil left in the head bolt holes? Tighten them down like that = possible cracked block.

wow, good call. the first time it went back together there was a little oil left in one hole (i thought it blew them all out, but apparently not). i didnt get too far torquing it before i removed it and cleaned it all out... but DAMN I bet that could be what happened. you win a cookie!

what a stupid mistake! rushing to get it done... nobody to blame but myself [headbang]

Scotty@Advanced
10-12-2011, 01:40 PM
wow, good call. the first time it went back together there was a little oil left in one hole (i thought it blew them all out, but apparently not). i didnt get too far torquing it before i removed it and cleaned it all out... but DAMN I bet that could be what happened. you win a cookie!

what a stupid mistake! rushing to get it done... nobody to blame but myself [headbang]

Drop the pan pressurize the cooling system and look for drips.

bman005
10-12-2011, 03:21 PM
My $ is on the block.

walky_talky20
10-12-2011, 04:04 PM
Just spoke with my father about this possible head bolt hole contamination issue. He said the amount of torque you need to apply to crack the block in that situation (hole not being dry) is far less than you think. Definitely before you even get the torque wrench out. It is also possible that you would not hear it. Further he said that it seems to him the VW/Audi engines are the most susceptible to this type of damage because they afford very little slop in the head bolt threads, unlike other manufacturers. For instance, he said he has never seen this happen on a Toyota, but has seen it more than once on a VW engine.

angry12v
10-12-2011, 04:17 PM
Just spoke with my father about this possible head bolt hole contamination issue. He said the amount of torque you need to apply to crack the block in that situation (hole not being dry) is far less than you think. Definitely before you even get the torque wrench out. It is also possible that you would not hear it. Further he said that it seems to him the VW/Audi engines are the most susceptible to this type of damage because they afford very little slop in the head bolt threads, unlike other manufacturers. For instance, he said he has never seen this happen on a Toyota, but has seen it more than once on a VW engine.

Wow, excellent information here, thank you (and thank him for me!) It makes a lot of sense, I'm 99% sure that is what happened...

It seems very possible that if the oil has nowhere to go as you're tightening the bolt, the pressure would pop the block. Indeed did not make it to the torque wrench, started feeling "fishy" when I was hand tightening with a 3/8" ratchet, I actually thought I had stripped it. I ran a bottoming tap down it to make sure the threads were ok and thats when I found the oil...

I've done a lot of heads before but never ran into this, I guess I learned my lesson this time. Anybody know where I can get a shortblock? [o_o]