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HondaDustR HondaDustR is offline
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Join Date: Jan 2007
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Quote:
Originally Posted by bobbydirl View Post
Thanks HondaDustR, I feel pretty good about not driving it after the coolant really started making it's way into the oil pan in a notable way. The thing is, I can't get it in my head how coolant can be forced up into that spot under the oil filter threads as shown in the picture.
That's exactly what scared me... Oil floats on water, which means the bottom of the oil pan where the oil pickup tube is is full of coolant displacing the oil. The coolant will then get sucked up by the oil pump and pumped through the oil cooler, then filter, and then into the oil passageways. The coolant pooling in the oil filter galley in that last picture should be oil only. Use this diagram and some imagination and you can see why this could be really bad. Rod bearings, especially #2, are sensitive to oiling problems.
Oil System Flow Diagram

If it still sounded tight and quiet last time it ran, you are probably ok, so don't despair quite yet. It just needs a good oil system cleanup, which I am not familiar with as far as the best methods. I'm just formulating my best guess on the fly here, but you would need to remove the oil cooler and OPRV and clean them out really good with some solvent. Drain the oil, fill with something cheap, replace the filter. Run until warm and drain. I do not know if this should be repeated. Replace oil and filter with what you usually use and hope the rods don't start knocking. It would probably be best to clean it out sooner rather than later, or at least drain out as much as you can, since coolant, or coolant and oil mixed may corrode the bearings and crank journals.


Good used NA 2.5L heads complete with valves are pretty easy to come by and a head job is pretty straightforward. Most of the trouble is all the disassembly and assembly, and cleaning the gasket surfaces really good without gouging them or knocking any debris into the cylinders to get jammed between the piston and the wall. The other part is to have the head gasket surface on the head measured for warpage at a machine shop and shaved if it's out of spec or you'll be coming right back.
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Old 01-25-2010, 02:15 PM
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