Oil in coolant. Need help ples!
#1
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Background: Block (94) was built about 9 years ago with ARP hardware (not sure if they were torqued to 40 or 60ft lbs as that was a huge arguement back when I built the motor), 84mm pistons, Mazda gaskets / seals and a 99 head with a minor p&p. The setup has about 9k on it and the majority of that is NA driving (it has been tuned like 4 times also). The car has seen a few trips up to 250 degrees about a year ago compliments of a bad tune and oil pressure is usually 60-90psi. Also I have drained the coolant numerous times since the intial build and have never seen oil in the coolant nor coolant in the oil.
I checked the coolant two weeks ago and found oil in the coolant but no coolant in the oil. We did a leakdown test with the engine warm at 100psi and had leakby of 3% - 7% on all cylinders. I tested the oil cooler at 100psi (via the coolant route) with no sign of failure. Yesterday we pulled and inspected the head, head gasket, and block. There are no obvious signs of head gasket failure or cracking. I am bringing the head to the machine shop today to have it checked out...is there anything else I should be looking at or for?
I have a cometic head gasket ready to go on it this time around and am planning on using the ARP hardware again.
Thoughts?
I checked the coolant two weeks ago and found oil in the coolant but no coolant in the oil. We did a leakdown test with the engine warm at 100psi and had leakby of 3% - 7% on all cylinders. I tested the oil cooler at 100psi (via the coolant route) with no sign of failure. Yesterday we pulled and inspected the head, head gasket, and block. There are no obvious signs of head gasket failure or cracking. I am bringing the head to the machine shop today to have it checked out...is there anything else I should be looking at or for?
I have a cometic head gasket ready to go on it this time around and am planning on using the ARP hardware again.
Thoughts?
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Dropped the head off at the machine shop. They looked at it quick when I dropped it off and said it probably isnt the head (or headgasket) but they are going to pressure test it and check its trueness.
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Good luck. If it does the same thing, then I would remove the oil cooler and try again (in case your 100psi test at room temperature wasn't valid). If it's still a no go, then it's time for a replacement block.
BTW, been down this road myself. Had an engine that made tailpipe steam. Cracked block. Dangers of learning how to tune. Fortunately, Miata blocks aren't expensive (unless you live in Hawaii, that is).
BTW, been down this road myself. Had an engine that made tailpipe steam. Cracked block. Dangers of learning how to tune. Fortunately, Miata blocks aren't expensive (unless you live in Hawaii, that is).