Oil dripping from under turbo compressor housing

Talk and Tech about turbocharged 924/944/968 cars
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Changed turbo a few months ago to a 27/6 hybrid from Evergreen. Currently mid -oil pan job, noticed an oil drip from the bottom of the compressor housing, on the backside where the retaining bolts are. Initially thought I had either not seated the turbo on the o-ring correctly or one of the mounting bolts had backed out and loosened. But I just pulled the turbo and o-ring is intact, doesn’t appear like it was kinked on install. Bolts were tight. Feed line on top the turbo is dry.

Current plan is to reinstall with a new o-ring on the return side and see what happens as I don’t see any other place that could cause a leak other than the turbo itself?

#1

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Normal for the two turbo mounting bolts to have oil on the threads when removing ?

Doesn’t look like it should unless the drainage o-ring is messed up ?

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Tom
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I would say no. If the bolts are wet from the top down, the mount is probably leaking.

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Strange. Both bolts mounting the turbo were tight. Seal was in the groove on the housing. K27 compressor so no other gasket should be needed. Unless the turbo or the mount is not flat, I don't see how it leaks from that spot.

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2 piece crossover pipe - the elbow to the waste gate inlet, I don’t understand how this forms a seal ? It seems to be a slip fit, but there’s nothing to apply tension to the cross over pipe? Am I missing a piece? It seems like the opening should be flared, then i could put the metal donut between the two flares and screw it together, but as it sits the donut and the flange slip over the elbow and just slides in and out on the crossover pipe, almost seems like I’m missing a spot weld or something on the pipe.

944online sells a new pipe but again… how does this form a seal?

https://944online.com/updated-waste-gat ... -pipe.html
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To clarify. With the flange and donut tightened . The elbow can slip in and out without too effort. Verify this is normal ? Seems like if the pipe can move in and out then so could exhaust gases ?
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Tom
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My guess is you just need a new donut. Yours looks pretty worn out....

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How would a new donut tighten down the pipe any more? It seems to be used to seal the two flanges. But my issue is the elbow itself physically can come completely out from the crossover, regardless of how well the flanges are sealed together. Should there be a spot weld on the elbow to prevent the flange from getting separated from the elbow ?

Unless when installed on the car there's a side force on the tube? Such that it's not moving or tightened straight forward/back out of the slip fit, but rather at an angle?

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The fresh donut has a little more meat to it - it expands radially (inward) when squeezed by the flanges. A fresh one should make that joint pretty stiff when tightened up.

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Ahhhh that makes a lot more sense thanks for the explanation

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