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Engine Oil Flush??

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budk1953

budk1953

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I've posted about high oil pressure ( crankcase breathers ) and received alot of good input from fellow forum members (more venting,etc.), to ideas from publications from the UK, and finally from an AMGBA consultant. Additional venting and/or changing the pressure relief valve is not a problem, but doing an engine oil flush (last resort before teardown)is something I hope someone else has done.Does this really work or just another way to sell oil products?
 
Was it high crankcase pressure or oil pressure. Two totally different things. Breathers won't really affect oil pressure but they would affect crankcase pressure. The relief valve and oil system flush would/could affect oil pressure. The crankcase pressure is a form of air pressure.
 
Hi,

I'm not a fan of engine flushing solutions, if that's what you are referring to. All that I'm familiar with are basically just thin oil and some solvents that are supposed to clean out sludge from the engine passages.

I have only used that stuff once, on a motorcycle (which had no sump pan to drop and clean out) and ended up needing an engine rebuild anyway. I can't say for sure whether or not the flushing caused the engine bearings etc. to wear more rapidly, but I'm sure it didn't help since it provides much less lubrication. It got some, but not all the sludge out of the engine. That engine had extremely low mileage, but had sat unused for 5 or more years and had something that looked like a La Brea Tar Pit inside it.

IMHO, far better would be to simply drop an engine's oil pan, clean out as much old sludge as possible and make sure the oil pump pickup is clear. Also pull off the valve cover and look for any gunk built up in there. If not too big a deal, the front engine cover is another place to look for any deposits of sludge, but whether it's worth pulling off depends on the engine and how easily it's removed.

Then reassemle it all run fill with oil, perhaps slightly lighter viscosity than usual, drive the car gently for a few days, maybe 100-300 miles, through several warming up/cooling off cycles. Finally warm it up and drain oil/change the filter.

It might pay to open up the filter to see what's being trapped in it. In particularly bad situations it might pay to use higher detergent (extended mileage) motor oils or repeat the drain/filter change process a couple times to clear out as much as possible from inside the engine.

I agree with Shawn, if you are trying to address problems with leaking, an engine flush is unlikely to help.

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