To CRYPTOKID
I had a similar experience with a used Honda I purchased about 6 months ago. The engine in this car had a coating of sludge when viewed from the oil fill hole in the cam cover. The existing oil had started to thicken and had not been changed for quite a while. My sludge build up was probably much less than what you have, maybe somewhere from 1/10" or 1/8" thick. Also the valve cover gasket and seals were starting to leak. My son was driving it and I couldn't trust him to keep a watch on the oil condition and level so i just changed the oil with my favorite brand of Shell Formula 10w30 with a Motorcraft filter and crossed my fingers.
He went off to school and returned mid semester with 3500 miles on the oil. To my surprise most of the sludge was removed and the oil was down 1/2 quart. I changed the oil and filter with the same Shell and Motorcraft and after an additional 2000 miles, 95% of the sludge was removed from the cam and valve area when I pulled the cam cover for a valve adjustment and gasket change to stop leaks. I was really surprised how well the oil only cleaned up the sludge in this engine. Now the varnish was not touched and a black and dark brown coating of varnish remained.
My recommendation to you is to remove the valve covers and clean out as much sludge as possible by scraping and then washing with mineral spirits or diesel fuel. Put it back together and use the Shell Formula oil of you choice of weight. Run for 500 miles, drain and clean the screen. Use the Shell oil again and check the condition after 500 miles. If the oil is black, change again. If the oil is brown then run to 1000 miles and change again. Repeat as many times as necessary.
I had a similar experience with a used Honda I purchased about 6 months ago. The engine in this car had a coating of sludge when viewed from the oil fill hole in the cam cover. The existing oil had started to thicken and had not been changed for quite a while. My sludge build up was probably much less than what you have, maybe somewhere from 1/10" or 1/8" thick. Also the valve cover gasket and seals were starting to leak. My son was driving it and I couldn't trust him to keep a watch on the oil condition and level so i just changed the oil with my favorite brand of Shell Formula 10w30 with a Motorcraft filter and crossed my fingers.
He went off to school and returned mid semester with 3500 miles on the oil. To my surprise most of the sludge was removed and the oil was down 1/2 quart. I changed the oil and filter with the same Shell and Motorcraft and after an additional 2000 miles, 95% of the sludge was removed from the cam and valve area when I pulled the cam cover for a valve adjustment and gasket change to stop leaks. I was really surprised how well the oil only cleaned up the sludge in this engine. Now the varnish was not touched and a black and dark brown coating of varnish remained.
My recommendation to you is to remove the valve covers and clean out as much sludge as possible by scraping and then washing with mineral spirits or diesel fuel. Put it back together and use the Shell Formula oil of you choice of weight. Run for 500 miles, drain and clean the screen. Use the Shell oil again and check the condition after 500 miles. If the oil is black, change again. If the oil is brown then run to 1000 miles and change again. Repeat as many times as necessary.