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2008 E350 4M, 2016 Audi Allroad, 2019 Audi Q5
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Discussion Starter #1
My 300TE has developed an oil leaking leaving a palmful of oil under the back of the engine when left after running.

I replaced the head gasket ~12k miles ago. Head was skimmed, pressure tested, cleaned, new guides...the whole 9 yards. I did the correct torque procedure...It's just weird....Got 100,000mi on the engine right now.

It is coming from behind the head. I have checked valve cover gasket and valve cover (swapped them both) and it still leaks oil. I am getting clouds of smoke from the oil splashing onto the exhaust manifolds in the AM.

It is leaking exhaust side. It is bone dry oil filter side.

1) Is there an oil gallery plug on the back of the head that could have been damaged at the machine shop? I've looked EVERYWHERE for a picture of the rear side of the 103 head and found nothing...

2) Any other ideas? Warped block?

Going to be pulling the head off again in 2 weeks so just a last minute post for information. This time around I will do a more detailed DIY that shows removal can be done without touching intake manifold.

Thanks guys
 

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It sounds like you are checking all the normal culprits. Since the upper timing case leak is so far upstream of the area you are finding wet, it doesn't sound like that is at play either. I have fouled up the cam cover gasket a couple of times (the half moon shaped piece of gasket that fits in the area created so the cam bearing boring tool could do its job) and they leak like the dickens when out of place, but you have been there too and seem to have confirmed its okay. Have you actually seen the leak originating at the parting line between head and block? Cleaned the engine down and looked for traces of the leak?
 

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Discussion Starter #3
It sounds like you are checking all the normal culprits. Since the upper timing case leak is so far upstream of the area you are finding wet, it doesn't sound like that is at play either. I have fouled up the cam cover gasket a couple of times (the half moon shaped piece of gasket that fits in the area created so the cam bearing boring tool could do its job) and they leak like the dickens when out of place, but you have been there too and seem to have confirmed its okay. Have you actually seen the leak originating at the parting line between head and block? Cleaned the engine down and looked for traces of the leak?
That is the issue, I cannot see where it is coming from since the gap to the firewall is too close. That is why I have this feeling it is coming from an oil gallery plug.

You can see the oil on the left side, and also a slight coolant weep on the right which is odd...Another hint towards possible head gasket?

 

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99 SLK230 Kompressor, 5 Speed Manual
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I hate to be the bearer of bad news, but all your evidence does indeed point toward the head gasket.

It worries me that you said that they "skimmed" the head. These long aluminum heads need to be straightened by heating and bending. It takes an experienced and savvy guy to do this correctly. If you "skim" too much it can cause problems.

Bending a previously milled head sounds a little tricky. Given what you've gone through, what would a known good head cost these days? Since these cars are now in the twenty years of age range, a head might not be that expensive.

Best of luck with it.
 

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About a dozen 1988, 1989, 1990, and 1991 sedans, wagons, 4Matics and 1 coupe
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Pic of back of head follows. It's even out of an 88. I'd triple check that stinkin' rocker cover gasket at the half moon area. I've screwed it up after being *sure* I had it right. Barring that there is the steel ball driven into the oil gallery bore access hole. Sure hope it isn't that. The thing below the steel ball is an overtemp indicator thingie affixed by the head rebuilding shop.
 

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About a dozen 1988, 1989, 1990, and 1991 sedans, wagons, 4Matics and 1 coupe
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As for an oil leak at the head gasket, there would have to be a pretty big problem back there. I don't think that there's oil under pressure passing through the gasket at the back end of the head. Here's a shot of the block all the way at the back. I think the small hole next to the bolt hole is for coolant. I *know* that the larger round holes in the protrusions are the oil drains going back to the pan.
 

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'92 300TE 4matic 280,000miles, '92 300TE 4Matic 'Ice Blue Metalic' 101,000miles
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Just a suggestion....I'd either steam clean back there or use engine Gunk-get the area spotless like augapfel's pic. Then do your duty run...shut it down and go in back there as far as you can with a inspection mirror-one that angles and telescopes. Use just the right amount of light to see the area....moving the mirror all around. You should be able to get a small inspection mirror to work....I think I could. If there's not a trail of oil originating between your head & block, you've saved yourself a hell of a lot of repeat work.:thumbsup:

Kevin
 

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I generally don't like to do this, but as a last ditch effort, you could try to re-torque the head bolts back there. Also, did you use an OEM headgasket?
 

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'92 300TE 4matic 280,000miles, '92 300TE 4Matic 'Ice Blue Metalic' 101,000miles
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I followed this thread originally over at another forum-he had very good advice & resources at his disposal. I wasn't there of course while he did the job, but he was very meticulous as he described the repair. If he torqued the head bolts properly and they 'settled in' correctly, he won't be able to budge them now except with brute force. They're not torqued at that point anyway, they are turned in sequence by degrees of a circle-90, if I remember correctly.

Kevin
 

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Yeah, which is why it's really a Hail Mary maneuver.

I'd be more inclined to suspect the gasket itself, especially if it's an aftermarket like Victor Reinz. I bought one a while back on a whim, and really wasn't impressed with the quality when I eventually inspected the fool thing after I pulled the head. I gooped it up as a precaution with a lot of that spray-on high-temp copper gasket dressing to fill in the gaps and pores. It's working great after a week, but I'll always kick myself for not buying an MB gasket for something so critical.

 

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99 SLK230 Kompressor, 5 Speed Manual
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Pic of back of head follows. It's even out of an 88. I'd triple check that stinkin' rocker cover gasket at the half moon area. I've screwed it up after being *sure* I had it right. Barring that there is the steel ball driven into the oil gallery bore access hole. Sure hope it isn't that. The thing below the steel ball is an overtemp indicator thingie affixed by the head rebuilding shop.
In the case of the M103 and M104 engines, they do indeed allow an oil leak at the return portion of the head gasket. Much more common on the 104, but it also happens on the 103.
 

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I did my own head gasket in June '08 by myself in my garage (91 300E 4Matic) and did not have a hoist, so had to unbolt the manifolds before lifting off the head...did OK. Had head checked, cleaned, resurfaced (skimmed). When reinstalling, the very last intake bolt (next to the firewall) would not go all the way in...I assumed there was some oil or other foreign substance in the bottom of the bolt hole. It was only about 1/2 inch, so I put a spacer in under the bolt head and everything has been operating fine since then, about 40,000 miles. Might there be something like that in the bottom of the head bolt thread hole in the block, keeping the headbolt from torquing down totally?
 

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'92 300TE 4matic 280,000miles, '92 300TE 4Matic 'Ice Blue Metalic' 101,000miles
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Like I said, he was trying to be meticulous about his head job and had a lot of good veteran advice. I'd be surprised if he didn't clean out and check the head bolt, block holes. However, only he can say for sure. And BTW, leaving the exhaust manifold on makes a pretty good handle for reinstalling the head with your hands. I had virtually no trouble maneuvering the light aluminum head in place by hand. Getting every bolt back in that intake manifold was however, not the easiest task I've ever done.

Kevin
 

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Discussion Starter #14
Been driving for a week now. Everything looks great. No oil loss, no coolant loss
:thumbsup:
 

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'92 300TE 4matic 280,000miles, '92 300TE 4Matic 'Ice Blue Metalic' 101,000miles
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But it took 8K to turn up a leak before? Just sayin'....but best of luck!

One way to tell if you got a good seal is to check the bolts about 500 miles from now. If it was done right and the surfaces sealed, you won't be able to budge/tighten the headbolts with any reasonable force.:thumbsup:

Kevin
 

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Discussion Starter #16

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'92 300TE 4matic 280,000miles, '92 300TE 4Matic 'Ice Blue Metalic' 101,000miles
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Good pics and writeup.:thumbsup:

I would suggest however, that they leave the exhaust headers on and replace with new exhaust gaskets after the head is back from the machine shop and still off the car. Infinitely easier to get to all the exhaust header bolts that way.

Also there needs to be something mentioned about the timing. The Service Manual's instruction and the resulting pic floating around the Net for the cam position is wrong for '89 and newer m103's. If you follow the book, your timing will be exactly 180 degrees off with the newer m103's.

Kevin
 

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Discussion Starter #18
Well for this particular change, you don't actually change the timing since you keep the sprocket and chain aligned. If the sprocket is removed though, you are right.

Good to know about that change though!
 

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'92 300TE 4matic 280,000miles, '92 300TE 4Matic 'Ice Blue Metalic' 101,000miles
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If the head goes to a shop and is cleaned/resurfaced, valve job etc, they most probably will look into their literature and come up with that same pic and present you with the head camshaft timed that way. Ask me how I know.....

Most people at this stage will have the head rebuilt...your case is unique because all you're doing is replacing the head gasket again from a past job-not a typical head gasket repair with mileage.

Kevin
 
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