I'm having trouble removing all the sludge out of my engine. Is there a proven way to get this stuff out of the crank without removing the bearings. I've heard sea foam works but I really don't know. Thanks

I have had good experience with seafoam. It wasn't a Bonneville, but it was a '00 Corolla that was burning oil and turning Mobil 1 pitch black. Ran seafoam through it, next oil change the oil that came out was actually pretty clean!

X2 regarding Seafoam.. It makes several products, and all are first rate. Follow instructions on the can.

X3 on the Seafoam. I also run cheap Walmart oil through till it runs out clean from the drain plug. usually takes 5 bottles of 10w40 to flush out my engine.

I have had great luck too with Wal-Mart oil. It has some excellent cleaning agents in it. I noticed the last time I ran some 5W-30 for a couple of days just to flush out an engine before installing "good" oil, when I drained the Super Tech oil, it took most of the brown color out of the aluminum cylinder head casting.

Under normal conditions Mobile 1 will keep an engine clean. Sea foam will clean a dirty engine very well. To keep this from happening in the future, you need to find out what happened to cause the sludge and fix it. It could be not changing your oil, overheating, excessive wear or a low grade oil that won't last the proper duration for your oil changes. My 265,000 mile engine is clean with Mobile 1 high mileage 15,000 mile oil with oil changes every 8,000 to 10,000 miles. For me this is 4 oil changes a year. I cleaned it out just by switching oils. The oil ports were clogged up (causing overheating) with buildup from PTFE (teflon) additives in previous oils. Never again.