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Hello gurus of automotive knowledge. As my wifes 1980 Cutlass Calais with a 267 v8 burns a little oil, she devised a strategy to stay ahead of the game and not risk letting the oil level get too low. The strategy was to add 1 litre of oil every 2 weeks without checking stick. I noted the oil press gage reading 0 1 day so I checked the oil. What I found was an oil level nearly a foot above the add line. As the engine was running very rough and gutless, I took it to my mechanic who said the engine problems were likely a result of cam lobes wearing and not the oil overfill. I believe this to be an inaccurate diagnosis as the engine problems started somewhat suddenly and wearing of cam lobes would be a gradual change. Although not a mechanic I am well versed in mechanical principles and have a theory as to the engine problems. My theory is that the excess oil somehow has fouled valve seats with carbon deposits thus affecting their ability to close tight.

Please advise best method and or products to effect removal of carbon deposits. My father RIP had told me of a method using water to remove carbon deposits vis-a-vis introducing small amounts of water through the carb on the premise of using the power of its expansion to steam to blow the carbon out?

Neil
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I would drain the oil to a reasonable level and see if it quiets down after a while.

Water decarboning can be done with a hot engine in the driveway by slowly pouring a trickle of water in the carb throat (or throttle body if EFI) while keeping rpms up. Engine must be good and hot. If you dump too much water in you may kill the engine or you may KILL the engine if enough water goes in to hydrolock a cyliner, which would result in a smashed rod and associated damage. I think water decarbon would work better cruising the freeway because you would be under load.
If you'd like, go to www.fullsizechevy.com and check out the forums for a post listed under "seafoam!!" I have never used this stuff, but there is a discussion concerning members there using it to clean out the carbon in their engines. Apparently it works as many there recommend it. I have seen it at the Auto Zone here in Humble - if I ever have a carboned up engine I reckon I'll give it a try. Good Luck DV
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