[Richard and Rhonda]

Russ,

I am thinking head gasket because I have violent bubbling in the coolant tank. Violent.

Conventional wisdom from the bus boys is head gasket. My next guess would be a severe crack in the head, and lastly a cylinder liner.

Seems that the pre 2000 Series 60's need upgraded head bolts. Hmmmm, expensive way to learn that I guess.

It if is something as simple as a head gasket, I hope I didn't erode the block or head enough to require machining.

Also, it seems that a common problem is that the cylinder liners can recede into block causing the same issue.

My worry is that I cooked the bearings in the lower end.

After further thought and review I think this has been coming for some time. Starting about two years ago, I had the feeling that I was losing coolant. Not a lot, and I had too small of an overflow tank at the time to separate lost coolant from the inadequate tank issue. I think something finally let loose on this trip. Once I installed a big overflow tank (bug sprayer jug) I began to notice something curious. Coolant would go into the overflow tank, but it would not go back into the engine when the engine cooled down. I now know why. Normally a vacuum would be formed as the engine cooled and suck the coolant back into the radiator. If I had a small breach then it would have broken the vacuum and hence the coolant not returning to the engine like it should.

The interesting thing is that all indicators on the VMSPc are absolutely normal. I drove it back home at 65 mph and got 7.2 mpg.

It will be a while before I can look into this. We are moving the next couple of weeks, buying one house, selling another, and I have this little thing of trying to come up to speed in a new assignment. Getting the coach back to storage meant that I could deal with the problem at my leisure, in other words, after I get the rest of my more urgent life issues sorted.

I will post on what we find, but right now if I had a Series 60 prior to 2000, I would be finding out if the head bolts had been replaced.