Head Gasket External Oil Leak

[Macgyver]

97 Saturn SOHC. Bit of an interesting issue I ran into. This car was brought to me with a cracked cylinder head (oil/coolant mixing). I put a reman head on (https://thecylinderheadshop.com) and after driving the car I noticed oil leaking out of passage that feeds the head near cylinder #1.

I figured I rushed through the job the first time (I’ve done 6 or 7 head gaskets on Saturn’s before) and replaced the head gasket (Fel-Pro) and head bolts a 2nd time. It’s still leaking and only leaks while the engine is under load. You can idle it for 30 minutes and the leak will never appear. I’ve added leak dye so you can easily see oil pooling right on top near the alternator.

Anyone have any suggestions? I’ve posted below the exact steps I’ve done each time – not sure why this engine is giving me trouble. Should I replace the head gasket again and add a layer of copper coat to it for additional sealing? I’m certain I torqued the bolts exactly as specified the 2nd time around.

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Initial dry bolt torque in sequence to 48ft-lb following the torquing pattern in stages to 20ft-lb, 30ft-lb, and final 48ft-lb. This establishes the proper clamp load on the gasket. This is followed by removal in about 1/4 turn in sequence until loose. Bolts washers and bolt heads are oiled with clean engine oil and reinstalled finger tight.

Torqued in sequence to 22 ft-lb then 33ft-lb and then additional 90 degree turn.

Torquing sequence
intake side
8-4-1-5-9
7-3-2-6-10
exhaust side

[OldNuc]

I have fixed that by slightly tightening that head bolt. You want it not quiet as tight as a dohc.

[billr]

How was the block deck checked for flatness?

[Macgyver]

Originally Posted by OldNuc

I have fixed that by slightly tightening that head bolt. You want it not quiet as tight as a dohc.

So an additional 5 ft/lbs on just that bolt even though I've torqued them 90 degrees?

And I did not check the block for flatness. There wasn't a prior oil leak at the head and my straight edge is 4 feet long - not enough to fit inside the engine bay. I'm not saying it's not possible, but I've never known the S series blocks to warp, it's always the head if anything.

[Macgyver]

Just an update on this if anyone has a similar problem. Tightening just the one head bolt did not fix the problem so I re-did the work again. The leak has now stopped completely and the car has been driven 500 miles (the leak was immediate prior). Outside of the normal scotch brite pad / acetone combo for cleanup when replacing the head gasket:

1) I ensured the block and head where straight using this (https://www.amazon.com/gp/product/B01DQCBHJ6/) and probing with a 0.0015 inch feeler gauge to ensure both mating surfaces were straight. Both were straight.

2) I coated a new Fel-Pro head gasket with 4-5 light layers of Copper Coat (https://www.amazon.com/gp/product/B000M8NZ8E/). Fel-Pro says not to do this, but whatever. I couldn't take the chance of this not sealing again.

3) I used DOHC torque specs instead of SOHC (an additional 5 foot pounds is used prior to the 90 degree turn).


Out of the multiple head gasket jobs I've done on the S series, this was a one off. It was very odd and I still have no idea why there was all this trouble.