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Need help - oil analysis shows coolant in oil

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I searched and found many threads that suggest head gaskets on RB engines don't often fail, but since I received an oil analysis that shows a slight amount of coolant in the oil, I pulled the heads. Head gaskets and heads look fine. I don't see any obvious cracks in the block, but I'm guessing a cracked block is be difficult to detect.

The car was running and driving normal, no white smoke, but there is oil residue in the coolant overflow tank, which was not there before. I only drove the car ~100 miles in the last month after being parked for a year. The only thing I noticed is the #8 piston was partially clean on the top surface. I'm guessing this points to a problem in cylinder 8. Any recommendations about what to do next are appreciated.

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The leak in on #8 cyl. You will notice that there is a lack of gasket impression on the block above the cylinder and coolant is entering the cylinder from the upper coolant hole between cyl 6 & 8. When the engine is at temp, the gasket seals, but as the engine cools, the gasket and head contracts creating a path for the coolant to enter the cylinder. The block should be squared, and heads could use a surfacing also. Another thing I see is that it looks like the engine has overheated (crushing the gasket). it also looks like the top row of head bolts on the driver side were loose due to the lack of a gasket impression not to mention the bolts were loose around cylinder 8, likely contributing to the problem.
 

@69Bee - Thanks for your analysis and the observation about the lack of gasket impression. The engine has overheated a few times for different reasons. The attached pics show more evidence of what you describe. Head bolts were all torqued requiring what seemed to be the same amount of force to break them loose.​

I've had the car for 17 years and never needed to open the motor. I have a set of 440Source Stealth heads and new bolts. I'll put it back together and hope for the best.​


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The block should be squared

I have a set of 440Source Stealth heads and new bolts. I'll put it back together had hope for the best.

I'm sure no expert but i think what @69Bee said is a good idea.
At least if it was mine i wouldn't want to just hope for the best and then possibly have to pull the engine again and do it all over.
I would want to be sure the surface from the block is straight before putting it back together.
 
Find, rent, steal a straight edge and check the surfaces.
Mike
 
I'm sure no expert but i think what @69Bee said is a good idea.
At least if it was mine i wouldn't want to just hope for the best and then possibly have to pull the engine again and do it all over.
I would want to be sure the surface from the block is straight before putting it back together.
Totally agree. If the motor was already out of the car, I’d get the block surfaced and do a full rebuild. Given the motor is in the car, I can have it all back together in a few hours and back on the road. I can always pull it and rebuild if there is a problem.
 
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The leak in on #8 cyl. You will notice that there is a lack of gasket impression on the block above the cylinder and coolant is entering the cylinder from the upper coolant hole between cyl 6 & 8. When the engine is at temp, the gasket seals, but as the engine cools, the gasket and head contracts creating a path for the coolant to enter the cylinder. The block should be squared, and heads could use a surfacing also. Another thing I see is that it looks like the engine has overheated (crushing the gasket). it also looks like the top row of head bolts on the driver side were loose due to the lack of a gasket impression not to mention the bolts were loose around cylinder 8, likely contributing to the problem.
Glad I looked - that's awesome!
 
Be sure and chase the threads in the block for the head bolts with a bottoming tap before you put it together.
 
Be sure and chase the threads in the block for the head bolts with a bottoming tap before you put it together.
Thanks for the tip. Just trying to learn...why do the threads need to be chased?
 
As mentioned use a straight edge to check the block and heads are flat. Chase / clean the head bolt holes to make sure the bolts torque correctly.
I don't think the bolt would be too long to bottom out unless the bolt holes have junk in the bottom of them? When in doubt, mockup the heads on the block and make sure the bolts run all the way down with little effort without the bolt washers (could even leave out the head gasket too.) That way when you add the gasket and bolt washer you know nothing is messing up your torque reading.
I would just get the Fel-Pro 260-1001 gasket set and use the included 8519PT1 head gaskets.
Fel-Pro 260-1001 Fel-Pro Engine Gasket Kits | Summit Racing
You will still need an intake valley tray/gasket.
Fel-Pro MS96000 Fel-Pro Valley Pan Gaskets | Summit Racing
I use the ARP Ultra Torque lube on the bolts, But is is not cheap.
The 1 oz packet is $5
ARP 100-9913 ARP Ultra Torque Fastener Assembly Lubricant | Summit Racing
1/2 pint (8oz) is $20 ($2.50/oz)
ARP 100-9910 ARP Ultra Torque Fastener Assembly Lubricant | Summit Racing
1 Pint (16 oz) is $29 ($1.81/oz)
ARP 100-9911 ARP Ultra Torque Fastener Assembly Lubricant | Summit Racing
 
Awesome info and advice. Thanks for the links. Much appreciated.
 
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Clean the threads, screw bolts in by hand to the bottom and measure how high they are. I just had a block where a few were not tapped all the way down.
 
Appreciate all the help and advice. Back together and running better than ever with 440Source Stealth heads.

engine 08.26.22 6.jpg
 
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