My Advise...Don't disturb it.
If you have one or both heads off for other nonrelated work, then get the dismounted head cleaned up profesionally.
Until then, make sure the ventilation system, the PCV and related tubing is clear and clean. That will help prevent further buildup.
AND MAKE SURE TO KEEP A CLEAN AIR FILTER IN THERE TOO.
I've used those 10 minute flush products, where you add a quart of what seems to be kerosene, into the oil, "Idle" for 10 minutes, then drain oil and replace oil filter.
You will never see any difference in buildup viewed in the oil fill hole, but the oil pump screen and bottom of pan gets a bit less mucky.
I've done that at every 3k oil change on one car I owned until I felt a little better. I can't say for sure it did much good though, as I never removed the oil pan to confirm anything.
Some people say to never use those engine flush products, so I'm sure you will hear from them.
I know at a few auto dealerships, they offer an engine, internal cleaning service, where they pump gallons and gallons of hot chemicals through your motor. They reclaim the chemical, filter it through something, and reuse it. I never tried that though. Anyone here do have that done? Maybe that helps remove that black tar.
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Ron Dittmer - Driving A Mint 88GT, Automatic, Medium Red Metallic, Gray Interior, Black Lace Wheels, With Sunroof and Wing, in the Chicago area.
